Werowance builds a webster

[minh-thanh]

I don't know if this helps or...
But I have a few times do the same method
Lathe speed is slow and several times replace sandpaper

 

[werowance]

Thanks Minh Thanh, I actually took a very light skim cut to clean those swirl marks up. but just the regular tool marks left from the carbide tools are still there. although minute I got tired of sanding and wanted to try paint to see. I think it will look good. but the glue trick is something I had not thought of and is a very good idea

 

[werowance]

marks like these are all I'm trying to hide now. very difficult to get in those corners. the outside ring is pretty shiny and smoothe because it was so much easier to get sand paper on

 

[minh-thanh]

I always use this sandpaper to flatten big scratch and then with 100, 150 sandpaper. if you want glossy: 400, 600 ...

 

[werowance]

the wrinkle paint turned out pretty good I think

 

[Brian Rupnow]

Werowance--I see where you are saying the "nut came loose on the arbor" causing the gouges in the face of your flywheel. Can you explain that a little more? Whenever I put holes in the flywheels I make, I set them directly on the mill table and hold them in place with toe clamps on opposite sides. If the relief in the sides of the flywheel is small and I am afraid of running my drill into the mill table when it breaks thru, then I put a 1/2" plate spacer between the flywheel and the mill table. I center the spindle over the flywheel bore and use ordinate dimensions to locate the x-y positions of the holes.

 

[werowance]

i used an arbor like I would for say a slitting saw. it was actually left over from making the gear for the flywheel.
so on my rotary table I already had the er32 collet chuck mounted in it so I just grabbed that left over arbor which was the exact size needed and put the fly wheel on it and sinched down the nut (or kind of sinched it down) just like I did when making the gear on that same arbor. then mounted it in the collet chuck on the rotary table. once in the proper position I was drilling every 120 degrees. (actually I didn't have a 3/4 drill but I did have a school surpless auction 3/4 inch end mill) so that's what I used. but I didn't have the nut tight on the end of the arbor so when the end mill touched it spun the flywheel.

 

[werowance]

an arbor like this one, I just removed the gear and put the fly wheel on. it was actually the arbor for the small 24 tooth gear that I was using on the flywheel

 

[Brian Rupnow]

When you are cutting a gear, it puts very little torque into the rotary table. When you turn the rotary table so the spindle is pointing up vertically and then drill a hole offset from the centerline, it puts a lot of torque into the rotary table. I don't know if you have a DRO on your mill to let you use X-Y coordinates for drilling like I do or not. in fact I can't remember how the flywheel holes were dimensioned on the original drawings or not. EDIT---I just checked the original drawing and no ordinate dimensions are given, just the angle between the holes. Unless you have a softwear drawing package or are a geometry whiz, I can see where you had no choice but to do it with the rotary table.

 

[werowance]

Thanks Brian, to keep the angle preasure down I put the arbor all the way in the collet so the flywheel is actually resting against the collet. sometimes if need be I will stack a few washers between collet and flywheel if there isn't enough room for break through vs damage to collet from the break through. but not having it stick up in the air like the picture of me cutting the gear gives the fly wheel more support. so it doesn't want to lean when putting the down force of the drill on once side. and I don't have a functioning dro. I did purchase a cheap I-gauging dro a while back and it lasted about a month or so and was very inaccurate. often it would jump 1 or 2 inches just by moving say 1/4 inch so I never trusted it but it finally just quit working all together.

getting along slowly with things - something I was not looking forward to, the press fit of the gear to the flywheel, well it went perfect. maybe just a little bit to tight but the arbor press pushed it home. I used that 638 locktight you recommended. its like a gel instead of runny like the normal locktight I'm used to. makes it a lot easier to apply.

but that's all the time I had for fun stuff last night.

 

[Brian Rupnow]

That's a bit weird. My 638 Loctite is not a gel. It is runny.

 

[werowance]

got the crank web done this weekend, silver solder went every where on the rod dowel. I was soldering from the back side and it ran over the end and onto the front side. needle files and sand paper for an hour or so to clean it up on the front side.. wish I had more time in the shop but just couldn't get there with all the other things in life, but had a good weekend.

 

[ZebDog]

I don’t post much but I’ve been watch this build from the beginning and its looking good so far

 

[werowance]

Thanks ZebDog.

Brian here is the lock tight I'm using. almost the consistency of superglue gel whereas I am used to just regular runny superglue.

also got a start on a piston rod list night. not much done. but at least a start.

 

[deverett]

Tip for silver soldering:
To prevent the solder going where you don't want it to go, use an ordinary lead pencil and rub it on the 'clean' areas before fluxing. The solder will not stick to the pencil rubbed areas.
The old solvent based Tippex did the same job, don't know about the water based stuff.

Dave
The Emerald Isle

 

[Cogsy]

According to the figures given on the loctite spec sheet for 638 its consistency should fall somewhere between detergent and shampoo at 25 degree C.

 

[Brian Rupnow]

Yes Werowance--same stuff I use.---Brian

 

[werowance]

finished up the rod and nut for the crank pin. not the best looking rod in the world but accurate where it counts. also on the nut, It has a "design feature" in it. its tight like a nylock nut or a deformed rocker arm nut on a old chevy 350 to keep it from backing off. this actually was not intended and I believe it to be caused by the die I used. it was an American Vermont from I believe lowes die and a hex shaped one. I have heard something to the effect that most hex dies are for thread cleaning or thread repairing and not direct cutting. it cut the threads with ease but are tight. the tap I used (I tried 2 different ones, one taper and one bottom) which are for sure made for thread cutting both would go in and out of the nut with ease. but the nut is tight on the threads and after I thought about it, hey design feature, so it wont back off so easily. on the tip of the nut it has a neck cut on it so as to only hit the inner race of the ball bearings. will have to make a washer for the other side of the bearings.

 

[Brian Rupnow]

Looking really good!!---Brian

 

[werowance]

ok, starting on the exhaust cam now. this is my first cam ive made and I have over the years read and watched different approaches to making cams. I am thinking about the technique in this thread:

https://www.homemodelenginemachinist.com/threads/webster-engine-cam-question.23225/

and then I have a question about that thread, in the picture below the 2 flats marked in blue. are they really flat? if so that will be great, once I get the .562 cut down then it will be a straight shot to the tip or lobe of the cam right. in other words work back and fourth between 162 and 18 degrees until the bottom is half is .562 then rotate to 162 deg and pull until I reach the top and the flat should be done on that side right? repeat for other side.

I have read about offset turning as well as using the boring head and out of the 3 ways the post above is the way I would feel most comfortable with doing as long as I am reading it right.

I will start with a .712 dia rod so that the lobe has the .356 radius called for in the plans