# Old School Sawmill Edger



## Brian Rupnow (Oct 14, 2019)

I'm all "engined out". I've been thinking about something to build and run with one of my engines. I already have a sawmill, a buzz saw, a steam donkey winch, a drag saw and a wood splitter. I have been thinking of an edger. Once a log has went thru the main-saw in a sawmill, the resulting boards have bark on the outer edges. This requires a second cut to be made to remove the strip on each side of the board which are known as "edgings". Old school edgers had two sawblades on a common shaft. One sawblade was "fixed" in position, while the other sawblade could be moved on the shaft to accommodate different board widths. They also had powered pressure rolls on the outfeed and infeed to draw the uncut board into the saws and to feed it out the other side when the cut was finished. A later development were "Bull-Edgers" which had multiple blades with spacers between them, so a wide board could be fed in and finish size narrower boards and two "edgings" would come out. The edgings on each side fell down onto a conveyor that took them to the chipper, while the boards passed on thru to the sorting shed to be sorted, graded, and stacked to dry. I think that one of the old style edgers might be fun to build. The blade on my buzz saw is about 3 3/8" diameter and I can cut "logs" of 1" diameter into stovewood lengths. (about 1 1/2" long). I want to do a bit of research and see if there are blades about 2" in diameter.--I could probably use slitting saws intended for metal work.
http://bbs.homeshopmachinist.net/threads/56666-Model-Sawmill-Dreaming?highlight=sawmill
http://bbs.homeshopmachinist.net/threads/65982-Buzz-Saw?highlight=sawmill
http://bbs.homeshopmachinist.net/threads/65855-Model-Woodsplitter?highlight=sawmill
http://bbs.homeshopmachinist.net/th...am-Donkey-Engine?highlight=donkey+steam+winch
http://bbs.homeshopmachinist.net/threads/77077-Building-a-model-Drag-Saw?highlight=drag


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## Brian Rupnow (Oct 14, 2019)

I did find some 2" diameter sawblades. The sawed lumber from my sawmill is only about 1/8" thick, so these blades should be about right. The actual thickness  that a circular blade will cut is half of the saw diameter minus half of the hub diameter.
https://www.amazon.ca/Proxxon-28020-2-Inch-HSS-Blade/dp/B000S6DTT0


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## Brian Rupnow (Oct 14, 2019)

I find sawmill machinery fascinating. There were four sawmills in the village where I grew up, near Bancroft. Of course I only seen them from a kid's perspective. By the time I was old enough to understand what all the different machines actually did in a mill, all the sawmills were gone. I did spend a couple of years as an adult designing high production sawmill equipment and installing it. The thing I like most about the old sawmill tech, is that it was so "In your face". Very little was covered with guards and you could see all that beautiful machinery doing it's thing. Very unsafe and dangerous for the people who worked in them (My dad lost a couple of fingers running the "resaw" in the Bancroft planing mill), but very pleasing to the eye when done up as a model. Even the models are dangerous--You have to exercise good "finger awareness" when running them.---Brian


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## Brian Rupnow (Oct 14, 2019)

Okay--Lets think about what I need. Engine with a governor--Yep, I have half a dozen of those. 2" diameter sawblades--Yep, I can order them from Proxon or Harbor Freight. Shafting will be cold rolled steel in "stock" sizes . One sawblade is fixed--no problem. One sawblade has to be able to slide along the shaft but still be powered by the shaft, to adjust for different board widths. Maybe a double keyway, one on both sides of the shaft and long keys, with two keyways in the moveable sawblade hub.Two powered rolls, and two pressure rolls for infeed and outfeed. Not sure at the moment, but maybe diamond knurl 4 pieces of cold rolled steel to act as textured finish on rolls. Some profiled pieces of flatbar to act as anti-kickbacks on the infeed side of the edger. A frame to hold all the bearings and shafts, etc, in place. An infeed and an outfeed table---This is where I broke one of my own rules---NEVER THROW ANYTHING AWAY!!! When I was building my sawmill, some kind fellow in USA sent me a whole bag of 3/4" square oak. I used it to build my sawmill carriage, and hung the bag with the rest of the oak on a nail in my storage closet. Couple of years ago in a cleaning frenzy, I thought, "Aw heck, I'm never going to use that stuff", so I pitched it out.  Dumb Bastard!!! The sawblades are going to have to run at engine speed 1200 rpm or a bit faster. The infeed and outfeed rollers are going to have to run at considerably lower speeds, so some gearing is going to be called for. What have I missed?---Brian


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## Brian Rupnow (Oct 14, 2019)

Amazon was happy to take my money for two of the Proxxon blades.


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## Brian Rupnow (Oct 15, 2019)

A bit of preliminary layout work shows the two 2" diameter Proxxon blades. Since the center hole on these blades comes in at 13/32" diameter, that pretty well dictates the size of hub I can have. And of course, the hub outer diameter  pretty much dictates what the hub inner diameter can be. This in turn, dictates the size the shaft will be. Turns out I can use a 1/4" diameter shaft, which should work fine. The fixed blade is going to be locked in one position on the shaft. The moveable blade (which is moved to accommodate different board widths) must be driven in sync with the fixed blade, so to do that we have a couple of long keyways in the shaft, and a couple of keyways in the hub of the moveable blade assembly. As in all designs, the project must start with the items which are purchased and then the size of everything around the purchased components is "custom sized" to accommodate the purchased part, which in this case is the sawblades.


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## Brian Rupnow (Oct 15, 2019)

Since the movable saw must move on the shaft to accommodate different widths of lumber, that means that the hub must have an extended head on it to accommodate a "shift fork".


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## Brian Rupnow (Oct 15, 2019)

And, since this is supposed to be "Old school", we'll support that saw-shaft with a big old set of pillow block bearings. now that we have the bearings in place, that will indicate what the frame width need to be.


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## Brian Rupnow (Oct 15, 2019)

The edger has two driven rollers as shown, along with two pressure rollers from the top (not shown). The position of the top side of these driven rollers is determined by the fact that the underside of the board passing thru the edger does not interfere with the hubs on the saw blades. Positioning in the other plane is established by the fact that you don't want them so close to the sawblade that they touch it, and you don't want them so far away from the blade that the board will "bend" when it encounters the blade.


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## Brian Rupnow (Oct 15, 2019)

Locating all of the rollers and bearings lets me then design a frame to support everything. Still have to design infeed and outfeed tables and a "fence" to guide the board straight into the rollers. This all goes very rapidly, but will slow down a bit when I start adding the belts and sprockets which power the saw and the bottom rollers.


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## Brian Rupnow (Oct 15, 2019)

Add in an infeed table and an outfeed table, along with a material guide/fence, and that's almost got it. Only things missing are the anti-kickback fingers on the infeed side and the drives.


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## werowance (Oct 15, 2019)

so how will the boards be pulled through?  or since its a model will it just be pushed through by hand?


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## Brian Rupnow (Oct 15, 2019)

The infeed and outfeed both have powered rollers on the underside of the board, and spring loaded pinch rollers directly above them. They grip the board, feed it through the sawblades, grab it again on the outfeed side and power it all the way thru onto the outfeed table.


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## Brian Rupnow (Oct 15, 2019)

Looking up from underneath you can see the long handle sticking out at the infeed end. This handle position is adjusted by the "edger man" to change the distance between the saw blades to cut different widths of board.


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## johnmcc69 (Oct 15, 2019)

Cool stuff Brian!

 Keep it coming.

 John


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## werowance (Oct 16, 2019)

I can already hear the high pitch whine of spinning steel cutting lumber


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## davidyat (Oct 16, 2019)

Brian,
   This thread reminded me of the Hull-Oaks steam powered sawmill, I believe, in Oregon. Their band saw can saw a log so long that the guy adjusting the thickness of what is being sawed, is actually riding on the carriage. They create so much saw dust, that it's used to feed the boiler that creates the steam. Fascinating place.
Grasshopper


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## Brian Rupnow (Oct 16, 2019)

Today I am working on the drive for the saw blades and for the infeed and outfeed rollers. The rollers will operate at a much lower speed than the sawblade. This calls for a bit of trickery. In this picture you see a gear reducer I built about 10 years ago, with a sprocket on the output shaft. As positioned it would provide a great drive for the rollers, but any drive to the sawblades is totally blocked. I've had that small 8:1 gearbox setting around here for ten years, but today is the first time that I've actually went ahead and modelled it.


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## Bighoss (Oct 16, 2019)

Brian Rupnow said:


> I'm all "engined out". I've been thinking about something to build and run with one of my engines. I already have a sawmill, a buzz saw, a steam donkey winch, a drag saw and a wood splitter. I have been thinking of an edger. Once a log has went thru the main-saw in a sawmill, the resulting boards have bark on the outer edges. This requires a second cut to be made to remove the strip on each side of the board which are known as "edgings". Old school edgers had two sawblades on a common shaft. One sawblade was "fixed" in position, while the other sawblade could be moved on the shaft to accommodate different board widths. They also had powered pressure rolls on the outfeed and infeed to draw the uncut board into the saws and to feed it out the other side when the cut was finished. A later development were "Bull-Edgers" which had multiple blades with spacers between them, so a wide board could be fed in and finish size narrower boards and two "edgings" would come out. The edgings on each side fell down onto a conveyor that took them to the chipper, while the boards passed on thru to the sorting shed to be sorted, graded, and stacked to dry. I think that one of the old style edgers might be fun to build. The blade on my buzz saw is about 3 3/8" diameter and I can cut "logs" of 1" diameter into stovewood lengths. (about 1 1/2" long). I want to do a bit of research and see if there are blades about 2" in diameter.--I could probably use slitting saws intended for metal work.
> http://bbs.homeshopmachinist.net/threads/56666-Model-Sawmill-Dreaming?highlight=sawmill
> http://bbs.homeshopmachinist.net/threads/65982-Buzz-Saw?highlight=sawmill
> http://bbs.homeshopmachinist.net/threads/65855-Model-Woodsplitter?highlight=sawmill
> ...


I actually have a full size edger like the one you are building. It has not been used in years along with the circular mill with over a 50" blade.


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## Brian Rupnow (Oct 16, 2019)

Well, --this looks good.--But there's a problem. Since the bottom infeed and outfeed must revolve counter to the rotation of the saw, I'm going to have to add a "reverser" in there somewhere.


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## ddmckee54 (Oct 16, 2019)

Yup, either a mechanical "reverser" like you show, or just use a couple of long drive belts with one of them twisted 180° to change the rotation.  They would have had enough distance between the pulleys that twisting the belt is probably the way it would have been done back in those days.

Don


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## Brian Rupnow (Oct 16, 2019)

Since I am running double or triple o-ring drive belts, twisting them might work but it's simple to add in a reverse gear. now the rollers under the board and the sawblades are rotating in different directions.


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## Mike1 (Oct 16, 2019)

Brian, I may be wrong here but if you arrange your feed rollers to feed on the top of your boards would that do away with a reverser ?

Mike.


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## Brian Rupnow (Oct 16, 2019)

Yes Mike, it would. I'm just trying to keep the same configuration as I've watched on a dozen YouTube videos about sawmill edgers.---Brian


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## Mike1 (Oct 16, 2019)

Brian Rupnow said:


> Yes Mike, it would. I'm just trying to keep the same configuration as I've watched on a dozen YouTube videos about sawmill edgers.---Brian


Ok Brian I'm watching with interest.
Mike.


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## aka9950202 (Oct 17, 2019)

I  suggest you look for the  machine you plan to build on vintagemachenery.org. kieth  has many of the original  plan for belt driven machines. 

Cheers. 
Andrew in Melbourne


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## Brian Rupnow (Oct 17, 2019)

Andrew--Thanks for the tip, I will check that out.--Brian


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## Brian Rupnow (Oct 17, 2019)

I had to do some calling around to my old sawmill contacts, but I finally come up with a good edger man.


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## Brian Rupnow (Oct 17, 2019)

I actually did some real work today. I can buy the 12 tooth sprockets dirt cheap from the local Princess Auto, but they have no hub. First job is to make hubs for them. The material in those hubs was supposed to be cold rolled steel, but it machined a lot like 12L14. It seems to take brazing all right--I'll find out when I clean everything up.


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## Brian Rupnow (Oct 17, 2019)

The sprockets complete with hubs turned out quite well. If they fall apart at some point, I'll know you can't braze 12L14 steel.


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## werowance (Oct 18, 2019)

12l14 brazes just fine Brian in my experience.  I used that for the bj cicada engine to braze on the carb bung to the side as per plans.  I did 3 different cylinders worth of them.  they all brazed nicely (engine didn't run but not because of that).  have also done some other brazing on it for a head light bar for my tractor and its held up with tree limbs and everthing else dragging across and smacking it for several years now.

one thing I will note is when heating 12l14 really hot I see what looks like little beads of sweat.  little tiny ones.  I feel like this is the lead melting in it but still never hurt anything Ive silver soldered on.

another thing is 12l14 rusts like crazy.


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## Brian Rupnow (Oct 18, 2019)

Drove up north to see my 99 year old mom today, and made a side trip on my way back to see my best friend forever who had a stroke. Mom is okay, but has dropped a lot of her memories. Best friend, who is the same age as me had a bad stroke, was in hospital for three weeks and come home yesterday. He has no lasting physical effects, but has aphasia. He can't speak, can't spell, but can understand when others speak to him. He was very frustrated today, trying to tell me things but couldn't speak. He can get a few words out, and I'm sure that over the winter he will regain most of his speaking ability. One of my 2" diameter Proxxon saw-blades was delivered today, other is on back order. It is very sharp, but has no "offset" to the teeth at all. I really wish I had access to small inexpensive toothed belts and pulleys, but since I don't I will use O-rings instead.


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## Brian Rupnow (Oct 19, 2019)

First trick of the day was to make a hub for the sawblade so I can test it and see if it cuts. I made the hub as shown in the picture, then found a 3/8" fine thread nut and locked it up tight against the saw blade. I used some 638 Loctite on the threads. Then I drilled and tapped #6-32 thru the nut and the machined hub for a set-screw to lock the hub onto the saw shaft. Next trick will be to set the blade up on something to see if it does cut the boards  from my sawmill.


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## Brian Rupnow (Oct 19, 2019)

This video shows a test of the 2" Proxxon blade cutting lumber.


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## Brian Rupnow (Oct 19, 2019)

This is the textured infeed roller. There will be another exactly like it for the outfeed.


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## Brian Rupnow (Oct 20, 2019)

This mornings work was to complete the second "textured" drive roller and both plain "pinch" rollers.


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## Brian Rupnow (Oct 20, 2019)

I'm going to have to spend some money tomorrow. I want all the pillow block bearings (bushings) to be a contrasting color. If I was planning on edging a hundred board feet a day, I would definitely make them all from bronze. For the sake of a model, I can probably get away with brass.


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## Brian Rupnow (Oct 21, 2019)

I've learned more about sawmill edgers in the last week than I ever have in my life!! One of the things all edgers have in common is an adjustable fence on the infeed fence. The setting of the moveable portion of infeed fence is to allow wider or narrower edgings from the side of the board.--for instance if you have a rough sawn board with a big bark inclusion on the side, you can adjust the moveable fence to cut a wider edging than normal.


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## Brian Rupnow (Oct 21, 2019)

Today I made the two spring loaded brackets which support the pressure roll bearings. They don't look that involved, but I've managed to spend the entire day building them.


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## Brian Rupnow (Oct 22, 2019)

So far today I've managed to whittle out four "pillow blocks" for mounting the pressure rolls. They still need to be polished to remove any remaining machining marks. They are made from brass, which will work fine, since this edger when finished isn't going to see a lot of hours. On average it is taking about 1 hour per pillow block, which sounds ridiculous, but it is what it is.


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## Brian Rupnow (Oct 23, 2019)

Run, run--fast as you can
You won't catch me, I'm the Pillow Block man.
Dang, there was a lot of time to make ten of these things!!


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## ddmckee54 (Oct 23, 2019)

What???? No oil holes, they'll never last more than 10-20 years.

Don


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## Brian Rupnow (Oct 23, 2019)

Actually Don, oil holes will be added. I was more interested in getting them all finished. I still have to polish them up, and I will add the oil holes then.---Brian


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## Brian Rupnow (Oct 25, 2019)

YES!!!--First assembly. Everything fits and most of the bolts go in. Milestone event!! It's plain that I will have to open a few clearance holes, but all in all I'm very pleased. The true story will be told when I make the two cross-members that bolt the two side-frames in place. It's been a long day.---Brian


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## Brian Rupnow (Oct 26, 2019)

From what I have read, these edgers had a habit of "kicking back" a board and wounding the operator who was setting the board on the infeed table and pushing it through until the infeed roller grabbed it. I don't want any workman's compensation claims in my mill, so I have added a set of anti-kickback fingers to the assembly.


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## Brian Rupnow (Oct 28, 2019)

A change to the top-plate. I was going to make it from clear Lexan, but then today I remembered how sawdust sticks to lexan because of it's electrostatic properties. Top plate will now be made from aluminum.


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## werowance (Oct 28, 2019)

looking reall nice Brian.


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## Brian Rupnow (Oct 28, 2019)

I spent a large portion of my morning "fine tuning" my "pillow block" bearings. Real pillow block bearings are self aligning, whereby the actual bearing unit can orbit in the cast iron housing to prevent any binding. My one piece simulated pillow blocks weren't nearly as forgiving. When they were tightened down to the aluminum frame, the shafts were binding very badly and wouldn't rotate. The misalignment was very small. So small that conventional machining wouldn't / couldn't fix it. My reamers are too short to span across both sides of the frame. I ended up coating dummy shafts with #600 aluminum oxide paste and lapping (for lack of a better word) with my electric drill. The dummy shafts were, of course, made long enough to span across the frame and fit through two opposing bearings at once. During the process I removed the bearings one at a time for polishing and the addition of "oil holes". Final step was to remove bearings one at a time for a bath in laquer thinners, then scrubbed inside with a small brush to remove any remaining grit. Doesn't sound like much, but it eat up my morning. Yesterday it rained all day, and I missed my "Fat mans walk". Today was lovely here, so I walked much farther on the forest trails where I hadn't been before to make up for the missed walk yesterday. It was about 58 F today, and many of the leaves have fallen, but enough remain on the trees  that it is still very pretty. Seen a lot of new ground, and my legs are telling me about it tonight.


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## Brian Rupnow (Oct 29, 2019)

So, here we are with the new top plate and all of the bearings freed up. I put a stir stick into the edger just to see how it looks. The springs on the pressure rolls aren't strong enough, but they are out of a kit I had with about a thousand springs in it. I will buy stronger springs next time I'm downtown. I think that now I can go ahead with the infeed and outfeed tables and their end stands.


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## Brian Rupnow (Oct 29, 2019)

The infeed and outfeed tables are finished and installed. The infeed table position is perfect. The outfeed table is a few thou. to high, which means that the powered roller on the outfeed side is not getting a good grip on the wood. It's an easy fix. I will take 0.025" off the top of the cross strut that the outfeed table attaches to. tomorrow I will make the end stands.


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## Brian Rupnow (Oct 30, 2019)

Well, that almost finishes the easy parts. I still have to build and assemble the fixed and moveable fences, and then it will be the moveable saw hub and mechanism for shifting it right or left.


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## Brian Rupnow (Oct 30, 2019)

So, after far more time than I thought it was going to take, we have an adjustable fence. I haven't yet put the locking mechanism in that makes the moveable fence hold it's position. Adjusting the position of the fence allows the edger man to determine how much he actually wants to trim from the side of a board.Guess the locking mechanism will be tomorrows job.


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## Brian Rupnow (Oct 31, 2019)

Not an awful lot to show for today, but we do have a lock for the offset fence position.  Tomorrow will be the day to clean all the bits and bobs for the adjustable fence up and "final assemble" them.


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## Brian Rupnow (Nov 1, 2019)

This morning I finished the hub for the moveable saw-blade. The hubs are two part, with 3/8"-24 threads on them. That scrim of Loctite that you see has to be cleaned up after lunch, and then I start work on the shifter link that moves the saw right or left on the shaft, to cut wider or narrower boards.


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## Brian Rupnow (Nov 2, 2019)

Today we have something very slick!! The man running the edger has to look at each board he puts through the edger, and estimate how wide he can make the board, and still not leave any wain (bark) on the edges. For the side of the board closest to the fence, he can move the adjustable fence in or out. For the other side of the board, he must be able to move the other saw closer to or farther away from the stationary saw. I've just finished with the mechanism which moves the non-fixed saw, and it is so neat I figured it was worth a short video.


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## payner (Nov 3, 2019)

Looking good Brian , I've been following this build closely. Let me know when I can bring some " lumber " over .
Bill


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## jlchapman (Nov 3, 2019)

Very nice build!


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## Brian Rupnow (Nov 3, 2019)

Hi Bill Payne--Good to hear from you. thank you Jlchapman. 
I'm having a lazy day today. I used my broach to put a 1/16" keyway thru the hub of the moveable saw blade, and milled a keyseat in the saw shaft. I have to try and find some 1/16" keystock tomorrow. This is a tricky business, because although the key must be there to transfer torque from the shaft to the blade, it must still allow the sawblade and hub to move along the length of the shaft as shown in the previous post to let the edger-man set the distance between the moveable saw and the fixed saw to select the width of board he wants to "edge".


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## Brian Rupnow (Nov 5, 2019)

This mornings work was to machine a "cap plate" for the gear reducer, and the riser which will support one end of the overhead shafts. The reducer output shaft was shortened, and a sprocket which formerly had a 3/8" bore was "sleeved" to go on the 1/4" reducer output shaft. I am rapidly approaching the point where I have to make a firm decision on whether I use toothed belts and pulleys or machine my own pulleys from aluminum and use rubber O-rings as drive belts. Seeing as I just spent over $500 yesterday for a new milling vice, I'm pretty sure what the answer is going to be.


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## Brian Rupnow (Nov 5, 2019)

An executive decision has been made. I'm going to make my own pulleys and use o-ring drive belts. Originally I had all the pulleys at 2 1/2" diameter, but I have changed that to 2.0" because that is what stock I have. I have stolen the 25 tooth gears off of the reversing winch, because I doubt that I will ever use the reversing winch again.


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## Brian Rupnow (Nov 6, 2019)

I have an issue. The roller chain that connects the reducer output sprocket to the two textured rollers has no method of tensioning the chain. That's okay, because I can adjust the tension by moving the entire reducer up or down by using spacer blocks until the correct chain tension is reached. (Note that the actual chain itself is not shown in this model.) The problem comes from the fact that the overhead shaft bearing support which is bolted to the reducer moves up or down as the reducer does. The other bearing support which bolts to the side of the edger frame does not. This is a perfect application for self aligning bushings, which are a two piece affair, where the bushing has a spherical outside and the housing it sets in has a spherical inside, but a normal round outside diameter. I need four of these, to support the two 1/2" diameter overhead shafts. There are other things that I can do, but not as neatly as these self aligning bushings would allow. I'm looking for a source for these self aligning bushings that are inexpensive and available in Canada, and I haven't been able to find one.---Brian


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## ddmckee54 (Nov 6, 2019)

Wouldn't it be simpler to put in a Delrin rub block to tension the chain?  That is if you've got the room?  Some of the old farm equipment that my Dad had used oil soaked hard maple blocks for chain tensioners on the low speed stuff and they lasted for years.  The block would eventually wear out, but then again your not exactly building this thing to run untouched for years on end.

Don


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## Brian Rupnow (Nov 6, 2019)

Don--Thanks. I actually did think of that. I'm just looking at a couple of different things right now, haven't made up my mind yet.---Brian


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## Brian Rupnow (Nov 6, 2019)

That seems to work out just about perfect with the #35 chain in place and 1/4" of spacers underneath the gear reducer. I am going to make a plywood sub-base to mount the edger and the reducer to, as seen in the previous post. I can then fine-tune the spacers to give the proper chain tension.


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## Brian Rupnow (Nov 6, 2019)

It keeps growing and growing---Tomorrow I will build the plywood sub base and get everything anchored to it before I start messing with shafts and bushings. I haven't built any of the anti-kickback system, but I do have holes drilled and tapped on the infeed side of the main frame. My kid who works at Fastenal is supposedly getting a piece of 1/16" square keystock for me---if he remembers.


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## Cogsy (Nov 7, 2019)

Brian, if you're still looking for some cheap self aligning bushings you might want to consider cheap rose-joints (also known as rod-ends). I'm sure you could machine the base down into whatever mounting you need and they should be available in a range of sizes for not a lot of money. They won't handle super high speed but for low speed applications they should work fine.


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## payner (Nov 7, 2019)

Brian . What is the biggest size of the mounting bracket you can accept for the self aligning bushings ?
I'm thinking of the input shaft of a snowblower auger at the back behind the auger pulley . Also on the older home furnaces some of them used self aligning bushings on the fan .


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## Brian Rupnow (Nov 7, 2019)

Bill and Cogsy--Thank you for the ideas. The aluminum uprights that support the shafts are only 1 1/2" wide, so that is somewhat my upper limit dimensionally. I did consider the rod ends, and they are fine for self alignment, but the inner part is not bearing material.


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## payner (Nov 7, 2019)

Brian . The snowblower bushings are probably 3" diameter, not sure how small you can cut them down . I will go down and check my supply of  " stuff " .
Also if you need any bearings I have a large collection, mostly new in box .


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## Brian Rupnow (Nov 7, 2019)

I just spent an hour trolling the internet looking for self aligning ball bushings to use for the two 1/2" diameter overhead shafts. My conclusion is that while they might be the perfect thing for this application, they cost more than I am willing to pay. (Which is not that unusual.) I do have a trick that will allow the shafts to turn freely and costs me nothing. Since the gear reducer and the upright attached to it are free to move horizontally +/- about 1/8" and vertically +/- .030" without affecting the way that the roller chain mates with the sprockets, I can drill and ream both of the uprights for 1/2" i.d. oilite bronze bushings, insert the shafts, and let the position of the shaft actually determine where exactly the gear reducer has to set.  I will post more about this when I get the edger and gear reducer positioned on the base which I currently have under way


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## Brian Rupnow (Nov 9, 2019)

I believe this is going to be a beautiful thing. I have been busy the last two days building some small fixtures for a customer, but stopping to add another coat of clear to the plywood base every time I could. This is the first time I have actually set the edger and gear reducer on the base, and I'm happy to see that everything fits the way I had planned.


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## Brian Rupnow (Nov 10, 2019)

Found out a few things today. The roller chain is about the right length with 1/8" shims under the gear reducer. I tried adding a half link to the chain length, but that made the chain too long and it was still slack with no spacers under the gear reducer. I dummied up that big pulley on the gear reducer and drove it with an o-ring belt from my electric drill. Everything goes round and round which is always a good thing. I have to put some 0.020" or 0.030" shims under the bearings on the infeed textured roller so the roller sets marginally higher than the top of the infeed table. Right now it is only about 0.005" higher and can't get a good grip on the board to send it through the saw. I picked up my oilite bronze bushings for the two overhead shafts today from Princess Auto. (You can see one of them setting on the infeed table.) I will cut the bushings to the correct length tomorrow and install them in the tower that is bolted to the edger frame. Then I will put a 1/2" shaft through and mark the tower above the gear reducer to see where the shaft center actually falls.


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## Brian Rupnow (Nov 11, 2019)

The best laid plans of mice and men---When I built that gear reducer ten years ago, I attached the gears to the shafts with Loctite. Not very smart, but I was a newbee at the time. Now it seems I have to disassemble it all and pin the gears or add set screws to them. Phooee!!!


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## Brian Rupnow (Nov 11, 2019)

Things weren't quite as dire as I had thought.  Nothing has let go in the gear reducer. The roller chain sprocket that I have on the reducer output shaft has been sleeved down to 1/4" diameter from 3/8" diameter. I forgot to drill and tap new set screw holes, so even though the set screws were tightened they were only bearing against the sleeve, not the output shaft. I have both uprights drilled and reamed for 1/2" shafts, and they seem to be fine---with all the bolts tightened up the shaft still spins. The roller chain is a bit tighter than I expected it to be, so the 1/8" spacers underneath may have to become .150" thick, not the .125" that they are now. Some of this stuff you just can't tell until all the bolts have been tightened up.


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## werowance (Nov 12, 2019)

Brian, this picture below just makes me happy to look at it.  I think they call it tool or machinist porn but for some reason the recessed screws and such are just pleasing to stare at.  good job.


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## Brian Rupnow (Nov 12, 2019)

Werowance--Hard to slide lumber over the tops of socket head capscrews. The plate is only 1/8" thick so a counterbore wouldn't work. 
Today was o-ring pulley day at my house. Looks like tomorrow may be an o-ring pulley day too. Four down, three to go. I have ground a tool bit to the profile I wanted, so all grooves are plunge cut to a depth of 0.070". I am hoping to achieve the result shown in the attached drawing, which means that the 1/8" cross section o-ring will pick up traction from the sides of the pulley as well as from the bottom. The picture of the tool I ground isn't that great, but it has an 0.080" flat on the tip and an included angle of 50 degrees. There has been a raging blizzard here all day, with about 6" of new snow on the ground and 6 more on the way overnight and into tomorrow. No fat-mans walk today. I'm down 42 pounds since May, and have 8 more to go. May be walking in the mall until snowmobiles have packed down the snow in the bush-trails I generally walk on.


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## Brian Rupnow (Nov 13, 2019)

It took every last inch of 2" aluminum stock that I had, but all of the pulleys are finished.


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## CFLBob (Nov 13, 2019)

Four three-grooves, two two-groove and one six-groove.  I only see one three-groove in the drawing up top, and there doesn't appear to be a use for the outer three grooves on the sixer, so I wait with curiosity to see how this all goes together!


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## Brian Rupnow (Nov 13, 2019)

See post #22 Bob.


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## CFLBob (Nov 13, 2019)

Embarrassingly - I went to the top of this page and didn't see the link to the earlier pages.  For reasons I can't even guess at.  I'll catch up with this as we go along.


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## Brian Rupnow (Nov 13, 2019)

This afternoon seen the first assembly of the two overhead shafts, gears, and pulleys. I think I'm going to end up putting a bolt on gusset plate on the tower coming off the gear reducer, because right now things are more flexible than I am comfortable with. Tomorrows job will be to build the gusset plate and put set-screws into all of the pulleys.


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## ddmckee54 (Nov 14, 2019)

Brian:

It takes a special kind of crazy to go through this much trouble just to rip paint sticks to width.

That being said, it's looking very impressive.

Don


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## Brian Rupnow (Nov 14, 2019)

Don--I am a special kind of crazy, and I love it. I've been this kind of crazy for the last 70 years or so.


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## LorenOtto (Nov 15, 2019)

Brian Rupnow said:


> Don--I am a special kind of crazy, and I love it. I've been this kind of crazy for the last 70 years or so.


You go Brian!  Keep it up, I enjoy every new addition to your build.


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## Brian Rupnow (Nov 15, 2019)

So, I have arrived at the point where there really isn't much left to do except buy a bunch of O-rings for drive belts and "free up" all of the shafts which run in bushings. This picture shows my 1750 rpm motor "running in" the top two shafts and bearings. There is also one o-ring belt driving the saw arbor. I will keep lots of oil on the bushings and let it run that way for an hour.


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## Brian Rupnow (Nov 16, 2019)

For all intents and purposes, the project is finished. My next challenge is going to be getting the correct size and length of O-rings for drive belts. there is a local o-ring company that doesn't sell to the public, but who have helped me out before. There is also a seller in Toronto who I will contact on Monday. I am quite excited to see this edger working.--Brian


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## Brian Rupnow (Nov 16, 2019)

Just for the heck of it--Here is a picture of "running in" the textured rollers. There wasn't a lot of resistance there, but even a brand new piece of roller chain will loosen up considerably when "ran in" for an hour with lots of oil on the chain and the bearings which support the textured rollers. The spring loaded pressure rollers are tied up with a piece of string to keep them from being "imprinted" by the textured rollers while they are being run in. On full size edgers I am sure that there must be an adjustable stop to keep the pressure rollers from riding up against the face of the textured rollers


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## Brian Rupnow (Nov 17, 2019)

I received a quote yesterday for the eleven O-rings I want to use on this project. $55--Ouch. Still cheaper than buying one timing belt pulley. Remember--I'm not in USA. Everything up here costs roughly 30% more than south of the border.


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## Brian Rupnow (Nov 17, 2019)

I've decide to use one of my side-shaft engines for the edger project. This is not a hit and miss engine, but is a throttle governed engine. The governor mechanism senses when the engine begins to slow down from a load, and consequently opens the throttle wider to compensate for the load and bring the engine up to it's pre-set "no load rpm". I know this engine has more than enough power to drive my sawmill, so I am hoping it will have no problem driving the edger.


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## CFLBob (Nov 17, 2019)

Count me as anxiously waiting for video, as I'm sure many folks are.


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## Brian Rupnow (Nov 20, 2019)

This falls into the category of "wild ass ideas" but---On many of the small machines I make to run off my engines, I use o-ring drive belts. They work just fine. However, in order for them not to slip on the smooth surface of the aluminum pulleys, they have to be stretched very tight.  The fact of "being stretched really tight" is hard on the bearings of both my engines and the machines they run. What can I do to alleviate this problem?---Well, what about the idea of giving some texture to the smooth surface of the pulley grooves?
 I have a dedicated cutting tool which I ground to cut the pulley grooves. I know the geometry of the tool tip and consequently, the grooves it cuts. If I were to make a round cutter from 01 steel, which had the same geometry as the cutting tool, then drilled a series of holes around the thing and hardened it, it would leave the shape shown. If I then had a hole in the center for an axle and a holder, I could mount it in a holder in my quick change toolpost, and after lining it up with the pulley groove, crank it in far enough that it was giving some pressure. The pulley would be rotated by my lathe, and as it turned the new cutter would "imprint" a pattern in the smooth pulley groove. Remember, I'm not trying to remove material here, just imprint a pattern. Unless I got into one of those situations where the pulley groove was exactly a multiple of the cutter pitch diameter, it should not repeat the pattern in the same place on each rotation. I like the idea. I have enough material on hand to make something like this. What do you think?


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## werowance (Nov 20, 2019)

sounds interesting.  steel against aluminum should imprint easily - at least to a point of giving you some traction.  only thing I'm thinking about is burs or something similar to a knurl that might cause the oring to cut or grind away rapidly maybe?


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## Brian Rupnow (Nov 20, 2019)

Werowance--It's one of those "Try it and see what happens" kind of things. If I don't need it, I won't do it. If I decide that I do need it, I'll make one and it should last me for the next hundred years.


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## Charles Lamont (Nov 20, 2019)

Brian Rupnow said:


> I received a quote yesterday for the eleven O-rings I want to use on this project. $55--Ouch. Still cheaper than buying one timing belt pulley. Remember--I'm not in USA. Everything up here costs roughly 30% more than south of the border.


Why not try the round polyurethane belting? It is dirt cheap, you can easily make it up at any length you require, and being made for the purpose, which O-rings are not, it works better.


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## Brian Rupnow (Nov 20, 2019)

Charles--I didn't use round polyurethane belting because up to now I've never used anything but O-rings for drive belts. I do have a link that someone sent me to a place that sells polyurethane belting and connectors for it.


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## dsage (Nov 21, 2019)

How about a rubber pulley (hard but sticky) with an aluminum hub.
Rubber is easily turned on the lather when frozen. (pre-frozen or use freeze mist on the fly).
Perhaps just a slightly concave aluminum pulley (to keep the belt tracking) and a glued on layer of thin inner tube rubber.
I'm thinking any sort of texturing would just wear the belt.
Perhaps a bit late now but large pulleys would give more circumference and more grip.


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## dsage (Nov 21, 2019)

Another thought. 
How about a leather belt. Strips are easily cut and if the two ends are gradually beveled they are easily glued together - just like they used to do it - and fitting for your project.


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## Brian Rupnow (Nov 22, 2019)

I've had a rather lazy, non machining week and I've rather enjoyed it. I called the o-ring vender in Toronto, and they have my O-rings ready to ship on Monday. They were supposed to ship this week but something got screwed up with their supplier and they couldn't make it this week. I did get rather excited about the link posted by Jason, as it shows polyurethane cut-to length belting and a multi jointed mechanical connector, but more reading showed me that minimum diameter is 3/8", too large for my use. I actually did contact Fenner Drives to enquire about 1/8" polyurethane drive belts and a "splicing kit".  It is winter here now, and since I don't have any heat out in my main garage, I will probably set the edger, clutch, and engine up on a piece of 3/4" plywood on my reference desk beside my computer for the actual running.


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## Brian Rupnow (Nov 22, 2019)

So now we are going to see about old dogs and new tricks. I have always used black rubber O-rings as drive belts for the array of "Things to drive with my engines". That was mainly based on the fact that Hercules O-rings have a distribution warehouse in Barrie, and if I went over there and begged enough, they would give me what O-rings I needed. Time has moved on, and all of the personnel over there has changed so I doubt that my begging routine would do much good. The newest bunch of O-rings I am planning to use on my sawmill edger have been ordered from a Global O-rings in Toronto, and by the time I pay for the O-rings, the tax, and the shipping, I'm going to be looking at $75 or $80 which is a bit much. I have contacted a distributor of polyurethane Fenner drive belts (which are sold in 100 foot rolls, and a "welding kit" for joining the ends. According to people who seem to know, this round polyurethane belting is far less apt to slip on an aluminum pulley than an o-ring. I will post what I am quoted and also post what the O-rings I have on order end up costing, and let you know.---Brian


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## Brian Rupnow (Nov 22, 2019)

dsage--I'm not ignoring you. It's just the fact that my aluminum pulleys are already made. Leather belting works in some applications, but I'm not really a leather worker.---Brian


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## Brian Rupnow (Nov 25, 2019)

I'm still waiting for O-rings, but in the meantime, the brain never rests. I'm still thinking of a pattern embossed on the aluminum pulley in the area where it connects with the o-ring. The o-ring gets squeezed into a v-shaped slot with a flat bottom. If the sides of the v-shaped slots have an embossed pattern, I can imagine it tearing up the rubber O-rings fairly quickly. However, if the pattern was embossed only on the flat in the bottom of the groove, it would supply a lot of traction ensuring that the O-rings would be far less apt to slip, yet not tear up the O-rings. This makes the roller easier to fabricate. I can do a heavy knurl on the outside diameter of a 1" diameter piece of 01 steel, then part of a slice .075" wide and harden it. After heat treating it, put it in a handle as shown, mount the aluminum pulley on a mandrel and drive the pulley with my lathe. With the knurled piece held in my Q.C.toolpost lined up with the flat in the bottom of the pulley, then just crank the cross feed  down tight and let the pulley make a few revolutions. I have never seen this done, but it seems like a good idea.


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## Brian Rupnow (Nov 25, 2019)

A two hour heat soak in my wife's kitchen oven, and Hey-Presto--We have a new tool. The intent of this tool is to put a knurled pattern on the flat bottom of the v-groove in an o-ring pulley. Tomorrow I will do some functional testing and let you know the results.


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## Brian Rupnow (Nov 25, 2019)

Really outstanding results with this new tool. Two pictures show tool in tool holder after being cranked in to bear on bottom of v-groove. and an identical groove made with the same grooving tool to the same depth but with no texturing in the bottom. I wrapped a 1/8" o-ring around the smooth pulley, and with a bit of tension on it, it slips in the groove. Did the same with the textured groove, and there was no slippage at all.


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## Brian Rupnow (Nov 25, 2019)

This is the tool I ground to make all of the o-ring grooves identical. A simple plunge cut 0.070" deep and the groove is finished.


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## CFLBob (Nov 26, 2019)

I'm impressed.  Clever idea that worked as intended.  

I was showing this to my wife and she said, "patent it."   It seems like it's an obvious idea, but isn't that one of the tests for whether something is patentable?  That is, if someone "skilled in the art" recognizes it as novel and useful.


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## Brian Rupnow (Nov 26, 2019)

I don't see anything patentable. If my purchased knurling tool was narrow enough, I would have used it.  This was just a work-around. Use my purchased knurling tool to make something really thin, harden the result, then use the result as a narrow knurling tool. Neat as Hell, but nothing really new there.--Brian


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## Brian Rupnow (Nov 26, 2019)

Okay people--We have one side of the equation. This is a quote I received today for 100 foot of 1/8" diameter polyurethane cord and a splice kit.
From $83 to $94 for the 100 foot of cord, and over $500 for the splice kit.


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## cwelkie (Nov 26, 2019)

Brian - have you checked the following vendor as a potential supplier?  They are in the US but will ship USPS and I've had good service from them previously (no affiliation - just a customer).  If not for this project they may be an option in the future ... theoringstore.com
Charlie


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## Brian Rupnow (Nov 27, 2019)

SO--This morning my rubber O-rings showed up. There are 18.3 linear foot of o-ring, costing a total of $75.79 which works out to $4.14 per linear foot. The 1/8" round polyurethane that I had quoted was $83.00 for 100 foot. This works out to $.83 per linear foot. Conclusion is that o-ring material costs about 500% more than polyurethane material---if you don't consider the price of a splicing kit for the polyurethane.


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## Brian Rupnow (Nov 27, 2019)

Here we are girls and boys. Ready to rock and roll!!! It is far too cold out in my main garage to set this up, so I have it set up on a piece of plywood screwed to my side reference desk. The aluminum box with the switch and handle on it is my coil box. I'm going to grab some lunch and then try to run this thing.---Brian


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## Brian Rupnow (Nov 27, 2019)

I must have done something really, really bad in one of my previous lives. I'm all set up and ready to go, and I can't get the engine to run. It ran great the last time I used it, and nothing has been changed while it sat up on the shelf.  Rest of my day will be tied up figuring out what the heck is going on with the engine.


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## XD351 (Nov 27, 2019)

I must have done something bad in about twenty previous lives as my woes are never ending !  My motto is make it three times as one of them has to be close to right !

You could try threatening it with a suitably sized hammer ! I”m sure that me standing there with menacing look on my face and a 14lb sledge hammer slung over my shoulder  has intimidated at least three of my engine into cooperating!

Can’t wait to see it running !


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## Brian Rupnow (Nov 28, 2019)

If at first you don't succeed, try a different engine. That doesn't always work though. I put the vertical hit and miss engine on as a driver this morning, and it starts and runs like a champion.--But---It doesn't have enough power to drive the edger. I tried many different tricks, but when the clutch lever is engaged, the vertical hit and miss engine just grunts and quits.  This is rather bad news as all of my engines have a 1" bore. The stroke on the vertical hit and miss is slightly different (shorter) than the first engine I tried to drive this system with. I am now going to have a closer look at the throttle governed engine and see  what is going on with it. I think it is more powerful, but only if I can get the darned thing to run. I have a couple of tricks left. I can monkey about with pulley ratios, and if that doesn't work I have my opposed twin horizontal engine which should be more powerful.


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## Brian Rupnow (Nov 28, 2019)

I think I may have found out why my governor throttled engine wouldn't start. It may have been the result of a STUPID ATTACK!!! Having checked every possible thing I could, I decided that it must be a gummed up carburetor. So--I changed to a brand new carburetor.--And--While I was doing it I noticed that the top rocker arm on the engine operates the intake, not the exhaust. I have been bravely forging ahead with the engine valve timing set backwards. I don't have these stupid attacks often, but when I do, they're real doozies. I'm off to eat some lunch, then go for my fat mans walk, then come back and reset the timing. Gahhhhhh---


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## Brian Rupnow (Nov 28, 2019)

We're fine!!! Engine now runs excellent with proper valve timing. How did it get out of time just setting on a shelf? That is one of those questions that I have no answer for. I don't have anyone in my shop but myself, and unlike some people I could name, I don't have any shop elves. I know so much about these small engines, that when an engine refuses to run and yet I think everything is set up correctly, it makes me crazy. Now I will bolt the engine back onto it's sub base and see if it will run the edger.


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## Brian Rupnow (Nov 28, 2019)

The throttle governed engine does run the edger. There is an awful lot of stuff in motion and it's scary as Hell, but everything is working. I have to tame the engine down a little bit and get things moving at a more sedate pace, but I think this thing is actually going to work. I will post a video of everything working and a board going thru the edger --maybe tomorrow.


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## Brian Rupnow (Nov 28, 2019)

Three things to do tomorrow. Engine has one "loose" flywheel.---Drill out #8-32 set screw holes and retap to #10-24. Link between governor and carburetor need one end to be adjustable.--Right now there is no adjustment on it and I need it to be adjustable to set the engine rpm range. Spring loaded pressure rollers on edger have to have adjustable stops added. Right now they ride right up tight to the textured rollers. The boards I am going to be edging are 1/8" thick material, so the adjustable stops will stop the pressure rollers 3/32" away from the textured rollers. This will make it easier to get the boards into place to start them feeding thru the saws, and will keep the textured rollers from marking up the face of the pressure rollers.


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## PhilWroundrockTX (Nov 29, 2019)

Brian Rupnow said:


> SO--This morning my rubber O-rings showed up. There are 18.3 linear foot of o-ring, costing a total of $75.79 which works out to $4.14 per linear foot. The 1/8" round polyurethane that I had quoted was $83.00 for 100 foot. This works out to $1.20 per linear foot. Conclusion is that o-ring material costs about 340% more than polyurethane material---if you don't consider the price of a splicing kit for the polyurethane.


Just a comment: at $83.00 for 100 feet it works out to $0.83 a foot, not $1.20 a foot (@  $1.20 a foot it would be a cost of $120 per 100 ft). Makes the cost difference even greater.  Just a comment - I tend to do this sort of thing fairly often.


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## Brian Rupnow (Nov 29, 2019)

You're right. At $83 for 100 foot, that works out to 83 cents per foot. Not only am I old---I've forgotten how to do basic math!!!


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## Brian Rupnow (Nov 29, 2019)




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## Brian Rupnow (Nov 29, 2019)

I've played as much as I can for today. Tomorrows work will be putting swing limiters on the edger to keep the pressure rolls from riding on the face of the textured rollers.


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## Brian Rupnow (Nov 30, 2019)

This morning I put "swing limiters" on the pressure rollers. This does two things. It prevents the spring loaded pressure rollers from being forced down on the knurled feed rollers and getting their plain faces marked up by the knurling. It also holds the gap of about 3/32" between the rollers so that it isn't so difficult to force a 1/8" thick board between the  rollers to start it self feeding thru the saws. In the picture you can see the top of four #4 threaded studs with double hex nuts on them. They extend thru clearance holes in the top frame, thru the springs for the pressure rollers, and thread into the swinging mechanism which supports the top pressure rolls. By moving the nuts up or down on the threaded studs I can adjust the roller gap.   Right now I have a 1/8" thick parallel setting between the rollers until some of the Loctite I used on the studs sets up.


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## Brian Rupnow (Nov 30, 2019)

Today seen the first boards thru the edger. I'm a bit disappointed that none of my single cylinder engines have enough power to run it properly. I may try my twin cylinder opposed engine on it, however for now I wanted to see the edger actually do it's job. I have resorted to variable speed drill power, and although it is noisy, it gets the job done. I think that I need stronger springs on the pressure rollers to feed the boards completely through, but other than that it seems to do everything I want it to. I will get a video up either this afternoon or tomorrow morning.


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## Brian Rupnow (Nov 30, 2019)

I'm getting a complete education on the care and feeding of edgers. I am edging boards but I have learned---The saw's should be running twice as fast, and the feed rollers should be twice as slow. I have the feed rollers both gripping the board and passing it through just fine. Only thing is that the saw isn't cutting fast enough to keep up, so about half way down the length of a board the saw blades stall, and the belts slip. Fortunately, this can all be addressed by different pulley combinations.  I have an ever increasing bunch of different sized pulleys hanging on my machine-shop wall, from all of the crazy things I have built. If I put a board thru that is narrow enough to engage only one saw blade, things actually work pretty good.


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## Brian Rupnow (Nov 30, 2019)

You're making a pulley out of WHAT!!! Hey, it's free stuff. It will work fine in the application it is intended for. I didn't have any 1" aluminum plate. I coated the aluminum pulley with fast dry epoxy, and will finish it off tomorrow morning.


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## Brian Rupnow (Nov 30, 2019)

My original design had the feed rollers turning 8 times slower than the circular saws. This didn't work very well--the rolls would jam the wood into the sawblade so quickly that it would stall the saws. Next effort was to have the feed rollers turning 16 times slower than the sawblades. That worked a lot better, but would still jam the saws about halfway thru the cut and stall them. The wooden pulley I have up on the lathe right now is going to allow the feed rollers to go 32 times slower than the saws. I'll know a lot better tomorrow morning how that is going to work. It's been a fun day.


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## Brian Rupnow (Dec 1, 2019)

This morning we have success!!! The wooden pulley that I had up on the lathe yesterday seems to have done the trick. The edger is taking full length boards thru the saws and the feed rolls are gripping as I had intended. I had to make up an outside bearing support on the shaft which is held in my variable speed drill so as not put too much sideload on the drill bearings. This thing is noisier than I would ever have imagined. I am going to make a video now.


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## Brian Rupnow (Dec 1, 2019)

I have been trying unsuccessfully all afternoon to combine two separate videos into one. I can't figure it out, so two videos are going up. I strongly suggest that you watch them in order.---Brian


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## CFLBob (Dec 1, 2019)

That's just slick!  

I'm guessing the next step is to make an IC engine with the same horsepower as the drill so you can drive it from an engine you built.


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## Brian Rupnow (Dec 1, 2019)

Thank you, guys. Before I tear that set-up down I'm going to get my tachometer out and see what rpm the drill motor is turning at. It's horribly noisy, but I don't really think it's turning all that fast. EDIT---If I can trust my laser tachometer, the drill is turning at 1000 rpm, which is close to what I thought. That means the sawblades are turning at 2000 rpm.  The sawblades are 2" diameter. The 1/2" diameter feed rolls are turning at 62.5 rpm.


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## awake (Dec 2, 2019)

When will the OSHA inspection be held?


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## dnalot (Dec 2, 2019)

That's quite a machine. So how much will you be charging for your paint sticks?  

Mark


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## Brian Rupnow (Dec 2, 2019)

It's not so much the cost of the individual  paintsticks. It's securing the  timber rights from the federal government, building the camps, hiring the teams of mules and oxen, food for the loggers, and the rail transport from the paintstick reserve to my place. The price of the sawmill and the edger will only be a small portion condidered into the final cost per paintstick.


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## Brian Rupnow (Dec 2, 2019)

The big question here was "will the edger work" and if so then "what will be the final pulley reductions and sawblade speeds and what rpm will the feed rollers work best." I have now determined all of those factors. The initial form of the edger had far too many shafts and friction points for one of my gas engines to run. There is nothing else right now that I want to move forward and design or build so I am going to spend some time on a purpose built reducer that will give me the proper outputs and rpm's. The reducer which I used on this initial run was just one that I had setting around from 10 years ago. I want something that lets me get rid of the two top-shafts and the pulleys and o-rings associated with them.


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## Brian Rupnow (Dec 2, 2019)

So what does a design engineer do if he's bored?--Well of course--He designs something. In this particular case, a custom designed reducer to work with the edger. This will do three things, which may all be good. With full ball bearings on every shaft, this will cut way down on friction, and use up all the weird ball bearings that have been collecting in my tin of goodies. It also may give a far greater chance of the edger being powered by one of my gas engines, and it will keep me from totally forgetting how to cut gears with my mill and rotary table. It will also get rid of the towers and overhead shafts on the edger. I had accumulated six "bastard" ball bearings, some of which are metric and some of which are imperial, but they are all good bearings.--More will follow, tomorrow.


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## Brian Rupnow (Dec 3, 2019)

I dug around in my "someday I might use that" box, and Voila!! Not only did I find all of the orphaned bearings that I will use on my new gear reducer, but I also found a set of timing pulleys and a timing belt, which were rescued from a dead appliance?? One shaft from my reducer is going to extend from the reducer and sprocket side to the opposite side of the edger, where they will drive the sawblades.


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## Brian Rupnow (Dec 3, 2019)

Okay---Version two!! This is a much cleaner version. The overhead towers and shafts and pulleys are gone. All of the gearing  to get from 1000 rpm to 60 rpm is done by the gears inside the reducer I will build. This will dramatically cut down friction and noise. One of the gears which is running in the opposite direction in the reducer has it's shaft extended through to the far side of the edger, where a timing belt drives from the extended shaft to the saws.


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## LorenOtto (Dec 3, 2019)

Waiting anxiously for the latest iteration.  Good work.


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## CFLBob (Dec 4, 2019)

This is an interesting project, Brian.  Was the original approach based on something you'd seen, or an existing piece of equipment?


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## Brian Rupnow (Dec 4, 2019)

CFLBob--I grew up in a very small village in the "bush" in Ontario. My father was a logger. There were three sawmills all within walking distance of each other, one ran by water power, one ran by a steam engine, and one driven by a Cummins diesel. They all had an edger. I've probably seen a hundred edgers in my lifetime. I have never, ever, in seventy three years forgotten a piece of machinery I've seen.---Brian


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## Brian Rupnow (Dec 4, 2019)

There are a couple of 14 tooth gears in the new gear reducer I an building, and it is actually simpler if I make the gear and the shaft that supports it all from one piece. This picture shows the first blank, ready to have teeth cut in it. I used the auto feed running in reverse on the turned down area closest to the chuck. It worked fine, but felt very weird watching the cutting tool and carriage moving from left to right.


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## Brian Rupnow (Dec 4, 2019)

So---It's been a long and uneventful day, but I have two shafts turned to size and ready to have gear teeth cut into them tomorrow. Turning shafts to fit bearings is not one of the machine shop jobs that I really like. I have ruined so many pieces of shafting by trying to get that last thou off the diameter and then ending up undersize. Steel is funny stuff. Unless the lathe tool is razor sharp, it won't cut that last thou--it just burnishes the shaft. Then when you turn it in one more thou, it digs in and takes off more than you wanted it to. I generally take shafts down to about 0.002" oversize, and then work the final bit off with carborundum paper strips until it is a "perfect" fit. Sounds good if you say it real fast, but my thumbs are sore tonight from holding sanding strips.


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## awake (Dec 5, 2019)

Brian, what grit do you start with for the carborundum strips? I generally aim for .001" max over-size when I am going to do this, but have occasionally missed high and had to take down a .002 overage. I use two different grits, 180 and 320; if I am close (< .001"), I start with the fine grit, but if I am not that close, I can get it close pretty quickly with the coarse grit.


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## Brian Rupnow (Dec 5, 2019)

I've had a very gearish morning. We have one set-up shot and a shot of the three finished gears. No real excitement, I have the entire procedure written down in my "Gears" notebook. I don't do this very often, so it's nice to have something written that I can look over before I start machining. There is one more gear, made from brass, but it's a big one, over 4 1/2" diameter. I called my metal supplier to ask how much it would be, and he said "If you have to ask, you can't afford it!!"I have a good size piece of 1/4" brass plate that some kind soul gave me a few years ago, so I am going to laminate two pieces together and cut my gear from that. Now I have to go shovel the front step and go for my fat mans walk.


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## Brian Rupnow (Dec 5, 2019)

I have 120 grit and 200 grit sanding strips. They are 1" wide and come on a 100 foot roll.


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## awake (Dec 5, 2019)

Beautiful gears! I assume the larger one is keyed onto the shaft with the integral smaller gear?

With regard to the large brass gear - are you using brass for wear purposes? Wonder what a piece of phenolic or delrin or such would cost - I would think either would be cheaper than brass, but I haven't actually tried to source either in the size / shape needed for a gear blank.

I too have a large-ish plate of brass, close to 1/2" thick in my case, with some odds and ends of holes in it from its previous life. Every time I come to something that could use a large piece of brass, I find myself hesitating - is *this* the project I want to use this on? What if I use it now, and then *really* need it later on? Based on the history thus far, I'm guessing this piece of brass might be buried with me!

With regard to the sanding strips - I woulda thunk that 120 grit would get you there within a reasonable length of time. Are you using cutting oil with the strips? Especially, are you regularly floating off the build-up of swarf?

What I use are billed as "emery cloth" - don't know if that is any different from the carborundum strips you are using ...


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## Brian Rupnow (Dec 5, 2019)

I haven't actually got that far with my plan, but I'm thinking a .093" cross hole drilled thru the very large gear  that I haven't made yet and shaft for a Loctited in place 3/32" cross pin.  The larger gear that I have shown in the picture has enough hub sticking out one side to put a couple of set screws in, but I hadn't planned on keying it. I don't use cutting oil with the strips. All that does is immediately gum everything up and then the strips won't cut. I just went into my shop and read the printing on the back of the strips. Surprise!!!  It's not carborundum, it's aluminum oxide.


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## Brian Rupnow (Dec 5, 2019)

Whenever I cut a pair of gears, I always drill and ream two holes the exact calculated distance apart in a piece of scrap material and insert the gears and shafts, then turn them by hand to test how they mesh. Most times it works alright, but I have been fooled in the past. I can generally live with a bit of extra "lash" in the mating gears, but when they are a bit oversize, it gets ugly pretty fast. If they are a bit oversize, you can either set them back up in the lathe and recut them, which is a pain in the $#@%, or you can change the design of the housing a bit to accommodate them. Also, you can see my two pieces of 1/4" brass plate, rough cut to 4 3/4" and joined with J.B.Weld, then clamped. I will also bolt them together after they set up for 24 hours.


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## awake (Dec 5, 2019)

Brian Rupnow said:


> I don't use cutting oil with the strips. All that does is immediately gum everything up and then the strips won't cut. I just went into my shop and read the printing on the back of the strips. Surprise!!!  It's not carborundum, it's aluminum oxide.



Interesting that we have different experiences - for me, though I can use the emery cloth dry, it doesn't cut nearly as long, as it loads up with swarf, and there's no easy way to clear it. By contrast, cutting oil helps to "float" the swarf out of the grit; sometimes I just squirt oil on the emery strip, floating the swarf, but if that doesn't seem enough, I work the oil around a bit with my fingers, and then wipe it off with a paper towel, restoring it nearly to its original appearance before use. Could it be a different type of grit? I'll try to look to see what the "emery cloth" uses for grit when I get a chance to go out to the garage.


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## Brian Rupnow (Dec 6, 2019)

So here we are, ready to cut the 108 tooth gear. The two pieces of 1/4" brass plate were "glued" together with J.B. Weld, clamped and left overnight under a heat lamp. The outer circle of bolts hold the two plates together permanently--I don't trust any adhesive in an application like this. The inner circle of bolts pass through the plates and are threaded into a 1.5" diameter steel stub-shaft that is held in the jaws of the chuck on my rotary table. Before the stub-shaft was bolted in place, the brass plates were set up in my lathe 4 jaw chuck to drill and ream the 1/2" center hole. The stub shaft was also drilled and reamed for a 1/2" shaft, and you can see the end of it sticking out past the face of the brass plates. The big deal here is to achieve absolute concentricity before I start to cut the gear teeth. A dowel with a pointed end was first secured in the chuck, and then the center of the cutter was adjusted to be perfectly horizontally in line with the point on the dowel. Then the table was fed towards the column in the Y axis until the major diameter of the brass just touched the major diameter of the cutter. Then with the table cranked back out of the way in the X axis, the table was advanced 0.089" in the Y axis. This is the depth of cuts to be made. The table stops were set so that the cutter just cleared the brass part in each direction on the x axis. I am now ready to start taking full depth cuts every 3.333 degrees. This rotational distance is set by using the divider plates on the front of my rotary table.


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## LorenOtto (Dec 6, 2019)

Brian,
What gear cutter are you using?
LO


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## Brian Rupnow (Dec 6, 2019)

Loren--Using a #2 cutter, 24dp. I have a complete set of 8 cutters.


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## Brian Rupnow (Dec 7, 2019)

So, here we are with the completed gear-train for my new gear reducer. I cut the 108 tooth gear this morning, and after finishing it I set all of the gears up in the correct relationship to each other, and took it for a test drive on my milling machine.


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## Brian Rupnow (Dec 7, 2019)

The two main outer plates of the reducer have the exact same outer profile. Of course they have different cavities machined in the in facing side because of the mish mash of bearings I used. The easiest way for me to do this is to extend the small diameters of the blind bores completely through the plates. That way I can pick up on the bores when I flip the plates over to mill the cavities. There will be no pressure in the reducer, just lots of gear grease, so if I do extend the bores all the way thru each plate, I can glue in plugs after the fact. This makes my job a lot easier, and takes nothing away from the functionality.


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## Brian Rupnow (Dec 9, 2019)

Today seen the gears assembled with the first side of this reducer housing. The overall ratio will be 16.5:1. There is one trick thing going on here that I like. The 16 tooth pinion shaft sets so close to the mating 30 tooth gear that there is not enough room for two ball bearings to set side by side. That is why the reducer sideplates are 1" thick. This allows me to put in a deep counterbore for one of the bearings and a shallow counterbore for the other. That way I can run the ball-bearings with one setting in deep enough to clear the other.


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## Brian Rupnow (Dec 10, 2019)

This is a video of the reducer running. The gears are all finished and the shafts are all supported on sealed ball bearings. I still have to make and install the perimeter plates that enclose everything, as this reducer will be full of grease.


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## Brian Rupnow (Dec 12, 2019)

Today I made up the seven individual plates which form the perimeter of the gear reducer housing. Each plate has 4 drilled and tapped holes in it. Somewhere about half way thru, it must have driven me mad, because I thought "Now would be an opportune time to grease the gears before I get everything buttoned up!!" Of course by the end of the day, all of the grease is polluted by aluminum dust, so will have to be washed out and regreased. You have to admit though, it is a very swoopy looking gear reducer. It will look even swoopier after I wash out the bad grease, refill with good grease, and introduce reducer housing to Mrs. belt sander.


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## bmac2 (Dec 13, 2019)

Very cool assembly (again) Brian. You’ve inspired me to give it a try and make my own gear reducer for a sand muller I’ve been thinking of building. If nothing else I guess I have 3 months of winter to play with the idea.


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## Brian Rupnow (Dec 13, 2019)

So, today you get a look inside. The bad grease is all washed out, the joints are all sealed with compound, and the new grease is in. The outside of the housing has had a brief visit with a couple of different belt sanders. It is posed "more or less" in the position it will occupy on the edger. I have to machine a few brass "buttons" to plug any holes that I don't need, they will be installed with Loctite. That big pulley on the input shaft is not part of the finished assembly. I just needed something I could grip to test the gear train with.


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## Brian Rupnow (Dec 14, 2019)

Now that the gear reducer has been completed, it's time to go around to the other side of the edger and spend some time on the final drive for the saws. I had one set of timing gears and pulleys that were salvaged off some appliance, and they will be the only timing belt drives used on the project. The new reducer has one shaft that extends completely through the leg of the edger to drive the saw blade, and I have to do some very serious calculating to make sure the hole gets put into the correct place. I have ordered two Lovejoy couplings. One will go between the engine and the clutch, and one will go between the clutch and the gear reducer. No O-rings or pulleys will be used at all.


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## Brian Rupnow (Dec 14, 2019)

You just have to stop and admire a milling machine with such insane headroom. I don't use that head-room very often, but it is just wonderful to have it when you need it. I will have to put a tension pulley on that timing belt, but things worked out remarkably well. I will add an outboard bearing to that long shaft that comes all the way thru the edger to drive the large timing belt pulley.


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## Brian Rupnow (Dec 16, 2019)

So here we are guys---almost ready to rock and roll. I picked up my Lovejoy couplings this morning, and I have adjusted the height of all the components to be (hopefully) in line with each other, shaft-wise. As you can see, I have a bit of work to do yet, as the couplings need to be drilled and tapped for set-screws, and the wooden blocks under the clutch have to be drilled and glued together. I strongly believe that there were so many frictional losses with all of the o-ring drives and shafts on the first set up two weeks ago, that the gas engine didn't have enough power to drive the edger. I don't know this for sure, but it is what I think. Wish me luck. In another day or so we will be ready for the next test.


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## werowance (Dec 16, 2019)

good luck


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## Brian Rupnow (Dec 18, 2019)

Yesterday and today have been a voyage of discovery for me. I have tried three different engines on this set-up, one being my throttle governed engine as seen in the previous post. Next up was the hit and miss side shaft engine, and then the Rockerblock engine. All of these engines have a 1" bore and a 1 3/8" stroke, and none of them have the power to drive the edger. This surprises me, but  surprises are what you get when designing and building from scratch. Where do I go next?---Good question. I do have a twin cylinder engine that I built a few years ago, but it has a hand operated throttle. The perfect engine for this job would be throttle governed, whereby when there is no load on the fast idling engine, it does just that--sets there on a fast idle. As soon as it senses a load coming onto the engine, (because of the engine slowing down) it fully opens the throttle and holds the throttle open until the revs come back up to the "set point".  One of the problems with using my twin cylinder engine to run the edger, is that the "off" side of the crankshaft is not accessible to attach a drive coupling to. I can probably work around that, but there is the issue of tuning the twin into a throttle governed engine. I have to dwell on this one for a while before deciding what I'm going to do. The edger itself is a success. I will post more of this after it becomes a little clearer to me what to do. Merry Christmas to all of you.---Brian


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## CFLBob (Dec 18, 2019)

I have to say I'm a bit puzzled by the inability of the engines to drive this.  When the motor is slowed down by the gear box, doesn't that gear ratio reduce the horsepower required to drive the saw by that same gear ratio?  

Maybe numbers help: say it takes 1 HP to drive the edger and you reduce the speed of the drive shaft by a factor of 16.  Doesn't that reduce the power required out of the engine by that factor of 16?  (Minus any losses in the gears)  So a 1/16HP input from the engine would drive the edger properly, and depending on frictional losses, a 1/8 to 1/4 HP motor should drive it.  

Of course, I don't know what the HP of the engine is, but the displacement ((pi/4) * bore squared*stroke) is just over 1 cubic inch, so that seems like it should be capable of delivering a half HP.  Much more than 1/16 or 1/8.

Unless I'm all wrong in what I think I remember about the HP going down by the gear ratio.  If it goes up by the gear ratio, you'll never get there.  

One of my favorite proverbs: research is what you're doing when you don't know what you're doing.  


Merry Christmas, Brian.  No answer required here.


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## billco (Dec 18, 2019)

Brian Rupnow said:


> Yesterday and today have been a voyage of discovery for me. I have tried three different engines on this set-up, one being my throttle governed engine as seen in the previous post. Next up was the hit and miss side shaft engine, and then the Rockerblock engine. All of these engines have a 1" bore and a 1 3/8" stroke, and none of them have the power to drive the edger. This surprises me, but  surprises are what you get when designing and building from scratch. Where do I go next?---Good question. I do have a twin cylinder engine that I built a few years ago, but it has a hand operated throttle. The perfect engine for this job would be throttle governed, whereby when there is no load on the fast idling engine, it does just that--sets there on a fast idle. As soon as it senses a load coming onto the engine, (because of the engine slowing down) it fully opens the throttle and holds the throttle open until the revs come back up to the "set point".  One of the problems with using my twin cylinder engine to run the edger, is that the "off" side of the crankshaft is not accessible to attach a drive coupling to. I can probably work around that, but there is the issue of tuning the twin into a throttle governed engine. I have to dwell on this one for a while before deciding what I'm going to do. The edger itself is a success. I will post more of this after it becomes a little clearer to me what to do. Merry Christmas to all of you.---Brian



I am sure the answer will come to you 
Merry Christmas


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## Brian Rupnow (Dec 18, 2019)

I am looking at my twin cylinder opposed as perhaps being a candidate to run this edger. The only issue is that it has a manually controlled throttle on it. I want a governor controlled throttle, and am looking in to the possibilities of changing it over to governor controlled.


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## Cogsy (Dec 18, 2019)

The engines I've used with a throttle governor don't normally hold the engine at any sort of idle but rather limit the engine from over-revving while allowing full throttle as RPM drops. For the ones that are required to slow down to some sort of idle, there is normally either a manual or electronic control such that when the machine is 'kicked into gear' the throttle is opened for max engine power and then the governor takes over to limit them. My thoughts are if you set your engine at any sort of idle condition and try to maintain it, you won't be getting anywhere near full power from your engine.

I'm also surprised your other engines won't run the edger as I also would have thought they'd have enough power and I'm wondering if it's a similar issue. I recall during some of your builds where you've gotten an engine running before adding the hit and miss mechanism and you manage to make them run fairly slow even without the hit and miss. I'm thinking some settings (likely the carb) allow this 'idling' condition of the engine and if you don't change the setting even after you attach the hit and miss mechanism then again you won't make full power. In my mind, if you disconnect the governor on a hit and miss engine it should rev up to the point of exploding fairly quickly as you need it to be making a large amount of power with every hit.

Good luck with your build and I'll be following along as always.


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## TonyM (Dec 19, 2019)

To get our small engines to rev slowly we adjust the timing and carburation so that they run at reduced power. Just enough to maintain rotation at the lowest speed possible. In order to produce more power we need to reset our ideas and settings to a faster revving engine in order to get the power more relative to its size . I'm with Cogsy. It may just need a tweek of the timing and carburation to solve this.


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## Brian Rupnow (Dec 19, 2019)

Yes, you fellows are correct. When I first start and adjust my engines, I am setting up for the lowest speed possible when I video them, not the highest.  I did use three different engines tweaked to give me a higher rpm before trying to run the edger with them, but they simply didn't have the power output I needed.


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## dsage (Dec 19, 2019)

Horsepower = torque x rpm / 5252.
There is no way around that. The edger requires a certain torque (set by the friction of the mechanism and the job it has to do) and the rpm is set by how fast you want to do the job. Presumably you added the gear box to reduce the torque requirement of the engine but you also increased the rpm requirement. The formula still holds. The horsepower requirement didn't change.
In fact by adding the gear box you probably INCREASED the overall torque requirement because you added friction (in the gears etc). You can figure out the give and take on the whole mechanism.
 Horsepower comes from the fuel. You need to burn more fuel and you can get more power (torque) from the fuel by higher compression and (as suggested) possible timing changes. Most model engines are built to be lazy and inefficient. Perhaps it's time to design / build a performance engine or take your best engine candidate and increase the compression (at least),  improve the carburetor and run it at a higher rpm and add a governor.
 You might be able to estimate the horsepower requirement by measuring the torque required on the input shaft with a piece of wood in the edger and a lever arm and spring gauge on the imput shaft (or a torque wrench if you have one that goes low enough). Then multiply that by the rpm you want to turn it (back to the formula). You also need to measure your engine horsepower and match one up.
Perhaps your next project should be a simple Prony brake engine dyno.
  OR a simple dyno can be made from an electric generator (an electric hobby motor can be used) with a variable DC  load on the output wires coupled to your engine. You can measure the voltage and current output of the generator with couple of meters. One horsepower approx equals volts x amps / 746 . (there are estimated  losses that need to be added in there as well).
Where it would be cool to run your edger using one of your engines it is a very cool project in it's own right. I don't think it would degrade the project by running it from an electric motor.
Nice job.


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## Brian Rupnow (Dec 19, 2019)

Before I dive into this one, I want to set up the twin cylinder engine and make sure that I can tweak it manually to give a high speed of 2000 rpm and a low speed of about 1500 rpm.  I have a laser tachometer and can measure rpm quite accurately. Last night I lay in bed thinking about this. If I don't want the engine to ever exceed 2000 rpm, that can be accomplished by a hard-stop on the throttle linkage which doesn't really involve the governor. I would like to have a "mode" where the governor is disengaged so I can start the engine with the throttle closed and the governor completely "locked out" where the engine will run at about 850 to 1000 rpm . When I have the engine started and do engage the governor, I would like the governor to take the rpm up to around 1500 and hold it there under a "no load" condition. As soon as a load comes onto the engine and the flywheel shows the smallest inclination to slow down, I want the governor to immediately open the throttle fully, not incrementally, and take the speed up to full 2000 rpm and hold it there until the flywheels are no longer seeing a load and the engine can drop back to 1500 rpm until the next load is applied.


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## CFLBob (Dec 19, 2019)

dsage said:


> Horsepower = torque x rpm / 5252.



What units?  Torque in ft-lbs or in-lbs?  Or metric? 

Thanks


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## awake (Dec 19, 2019)

Brian, can you say more about how it doesn't work with the various engines - what the sequence or symptoms are? I believe you have a clutch between the engine and the sawmill, correct? I assume that the engine runs fine while the clutch is disengaged. But what sort of engagement is the clutch - is this a friction-type clutch that can engage slowly, or more like two castellated nuts that engage all at once?

I'm thinking about what happens with a manual transmission car or truck. The engine has plenty of horsepower to move the vehicle, but only if the torque is transferred gradually through a friction clutch. If the clutch is let out all at once, the engine dies. Could that be what is happening with the saw mill, or is it a totally different set of symptoms?


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## Brian Rupnow (May 9, 2020)

Today, just for giggles, I removed my new engine "Thumper" from the edger and replaced it with an old 1/4 HP electric motor. It worked like a charm, putting boards thru with no hesitation, with both saws cutting. I had hoped that my new engine would have the power to do this, because at 1 3/8" bore it has almost twice as much surface area on the piston as compared to my other 1" bore engines. Sadly, it didn't. Before I tear the set-up down off my worktable I may add a manual ignition advance to the engine, but I don't have high hopes for it.


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## CFLBob (May 9, 2020)

40 years as EE made me a fan of rules of thumb and other cheap and dirty mathematical approximations that can bound a problem for me.  Simple equations I can solve that give me an idea of the performance I can get.   Bear with me a second.  

The displacement of your engine is (pi/4)*(bore^2)*(stroke).  Simply the volume of the cylinder traced by the piston's movement.  I don't know what the stroke on that engine is but a cheating approximation there is that it's close to the bore, which you said is 1.375.  That's (pi/4)*1.375^3

That's 2 cubic inches.  Another approximation is that you're doing good to get the same HP as the displacement.  Yes, I know there's more involved when you get to power delivered than displacement, but displacement is certainly part of it.

That engine should be easily capable of 1/4 HP.  It should be capable of more than 1 HP.   

That tells me that it's likely to be down the road you're going down of advancing the ignition.  Or something to make it "run harder" when it's under load.


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## minh-thanh (May 9, 2020)

Add a suggestion: reduce the tension of the belts, reduce the friction of the parts, and reduce the thickness of the wood., maybe  solve the problem !?


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