# Kerzel hit&miss by Mike



## Naiveambition (Jun 17, 2018)

Hey all fellow modelers.  Finally picked a new project so this is my choice.    I picked this engine for a few reasons.  First being its I.C.  I looked strongly at the knucklehead by draw tech, Edwards radial five, and Ron colonna' offy four cylinder.   And decided these were above my pay grade and when done I want a running model. So felt Kerzel was a good start into ic and its related systems.
   Second is I can use this as a ongoing lesson with fusion 360.   My thinking here is to stick with one project and work thru it rather than multi projects in the learning forum. And maybe this will clear up some difficulties.     

I'm now on my third part.  When working on the con rod I ran across a ?. Hoping former Kerzel builders can help me out.   In the pic for the crank hole there is a . 376 inside dia. Then .437 dia.  What would this represent ? a chamfer maybe,? or is it also showing the bushing.  Elsewhere in the drawings is the bushing detail so wandering why it would be included in this drawing.     
Sorry guys I tried to post the pic but can't get it done. Keep hitting the pic Icon but nothing happens so let's throw that ? In there and I can post the pic tommorow


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## kvom (Jun 17, 2018)

The dotted line seems to indicate that it's the width of the shaft before the start of the curved portion.


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## Naiveambition (Jun 19, 2018)

After studying the drawing more, I think it would have to be a bushing, bearing.   The inside dia matches the dia of crank pin, then a split bronze bushing , with .437 being the con rod dia.   I wouldn't think the design calls for a steel to steel engagement which would make sense for the extra feature.   Even more so having a chamfer would eliminate the sharp edge of rod for oiling retention and galling.   
I've read thru most of Brian Rupnows  Kerzel thread and with his I believe he used a alum. Con rod which would enforce the bearing need.  
 I will also need to check all measurements for fit,   Caught one with the crankshaft bearing.  Outside dia. of crank bearing journals is..438 and inside dia of bearing is .437. Obviously just reversed when making plans which is understandable considering the amount of work laying out the plans.


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## jimsshop1 (Jun 19, 2018)

Naiveambition said:


> After studying the drawing more, I think it would have to be a bushing, bearing.   The inside dia matches the dia of crank pin, then a split bronze bushing , with .437 being the con rod dia.   I wouldn't think the design calls for a steel to steel engagement which would make sense for the extra feature.   Even more so having a chamfer would eliminate the sharp edge of rod for oiling retention and galling.
> I've read thru most of Brian Rupnows  Kerzel thread and with his I believe he used a alum. Con rod which would enforce the bearing need.
> I will also need to check all measurements for fit,   Caught one with the crankshaft bearing.  Outside dia. of crank bearing journals is..438 and inside dia of bearing is .437. Obviously just reversed when making plans which is understandable considering the amount of work laying out the plans.



I have built the Kerzel from Brian's plans and it is a fine running engine. Yes it is a aluminum connecting rod with a split bronze bushing. Have fun building it!

Jim in Pa


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## Naiveambition (Jun 24, 2018)

Ahh some light at the end of my tunnel.  Been working away on Kerzel drawings and here is where I'm at.    So far I don't have any red flags so am happy about that.     I do need to figure out which joints will make the model move correctly.   My crank is ok for motion but after that I am lost on the other correct movements.


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## Naiveambition (Jun 24, 2018)

Trying to draw up the head for the Kerzel tonite, and need some modeler wisdom.  2 issues hoping to resolve   

In the drawing  for the valve cage holes (lines a& b) how do I know the angle distance between the holes --- 360/ by 3?
 I see the radius of .219 for the hole layout but not a measurement for the moon shaped one.


And working on valve layout.  If my understanding is correct the valve seats are placed in the bottom of head vs the cage itself.  I'm guessing the 45'  seat is correct?  Hoping someone can guide me thru what the  "areas in port" section means, cuz this is all new ground for me


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## kvom (Jun 25, 2018)

The three holes look evenly spaced.


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## Naiveambition (Jul 18, 2018)

Ok engine completely modeled in fusion 360. Wow that is a major achievement for me      wasn't able to figure joint motion that would work in some cases like cam bobbin an pushrod. 

But I am now ready to start machining, but the more look at it , I'm thinking heavily of  going double scale.  My guess is it should end around the size of 1/3 scale, with 7 inch flywheels.   I like the more realistic, or lower revving sound of the larger models.  In my hometown the steam thresher reunion would display all sorts of past farm equip. And hit and miss is veery prevalent there. Met a fellow that prided himself on getting the most revolutions before the hit , but when it did it sounded like a shotgun going off. I don't think I ever not jumped when it hit  So got used to the sound and is what I'm shooting for plus the added size for constructions sake. (Small tapping not my forte)
Anyways ,  if I do upsize can I just double the model except for some needlessly thick parts.  I'm more concerned with the technical parts like the cam, stroke, piston clearance,  etc.


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## Naiveambition (Sep 26, 2018)

Finally around to cutting metal for this build. It is amazing how much more $ wise this motor is vs original size. Looking bout 400$ give or take.   Dont know if this is the tariffs talking or what, but every peice seems in the 80$ range.
I stressed over this mounting in every possible way for various reasons faceplate, line boring , milling, etc. and wasn't till I remembered the offset cut in the rear. This gave me just enough holding room to feel safe.  Overhang is definitely cumbersome, but with slow feed and rpm is working out so far
Starting out with a 3x5x5 block of 6061.  Here Im boring in stages, to keep my tool flex under control till the last few cuts, then will max out the overhang of my boring bar.   May make a one time use big bar to finish size.  This was the end of nite 1, with low rpm the cuts take forever so multi nights will be on order.


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## Naiveambition (Oct 6, 2018)

After too much trial and error I have made it to this point.  I am finding a lot my tools are to small or too big according to what I need for the upscale.  This piece has been particularly tricky with mounting.   I started in the 4 jaw then managed a taper somehow, then straightened on the mill.   I think the correct way would be line bore.  
Then turned the undercut for the water jacket.  Some chatter marks for pushing the bore cut.  Do you change your cutter style when doing undercuts? 
 Then onto rotary table after making centering disc for locating the bore. I must say me and my rotary table have a very love/hate relationship.  Locating ain't so bad but figuring how to mount is mind numbing lol.  
Was able to turn down and thread the face to 1/4 20.  Hopefully the scale works out.  I haven't made the head yet. And topped it off a little over for finishing
 later.

With this model I am wanting to improve my level of fit and finish by making different parts at different times rather than fit parts as I go.  Trying to teach myself  not cheat and force better results. This will be by far the most complicated model I've made. Trying to live on the thought " if I just make the parts to spec then all should be good." We will see.


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## PCT (Oct 7, 2018)

Naiveambition said:


> After too much trial and error I have made it to this point.  I am finding a lot my tools are to small or too big according to what I need for the upscale.  This piece has been particularly tricky with mounting.   I started in the 4 jaw then managed a taper somehow, then straightened on the mill.   I think the correct way would be line bore.
> Then turned the undercut for the water jacket.  Some chatter marks for pushing the bore cut.  Do you change your cutter style when doing undercuts?
> Then onto rotary table after making centering disc for locating the bore. I must say me and my rotary table have a very love/hate relationship.  Locating ain't so bad but figuring how to mount is mind numbing lol.
> Was able to turn down and thread the face to 1/4 20.  Hopefully the scale works out.  I haven't made the head yet. And topped it off a little over for finishingView attachment 104564
> ...


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## PCT (Oct 7, 2018)

It looks like you have a good start.  I completed a Kerzel this year, it was a fun project, but I'm still not able to get it to run for anything longer than a few seconds.  I'm sure I will solve that problem though.  At first run attempt, I had major problems with the mechanical points as shown on the plans.  The problem was that the point gap kept changing, I think due to faulty mounting to the block.  I eliminated the mechanical points and went with a Hall effect transistor and transistor ignition module from J.E. Howell
http://www.model-engine-plans.com/partskits/ignitionsystems/index.htm With this setup, I got it to pop and run briefly.  So, I think ignition is okay, carb adjustment might be wrong, or maybe not enough compression.  I haven't given up, I just need to find time to play with it.  Good luck with your engine, there are lots of them out there, some of them posted on YouTube, and they run fine.


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## GreggA (Oct 8, 2018)

Naiveambition said:


> After too much trial and error I have made it to this point.  I am finding a lot my tools are to small or too big according to what I need for the upscale.  This piece has been particularly tricky with mounting.   I started in the 4 jaw then managed a taper somehow, then straightened on the mill.   I think the correct way would be line bore.
> Then turned the undercut for the water jacket.  Some chatter marks for pushing the bore cut.  Do you change your cutter style when doing undercuts?
> Then onto rotary table after making centering disc for locating the bore. I must say me and my rotary table have a very love/hate relationship.  Locating ain't so bad but figuring how to mount is mind numbing lol.
> Was able to turn down and thread the face to 1/4 20.  Hopefully the scale works out.  I haven't made the head yet. And topped it off a little over for finishingView attachment 104564
> ...





Naiveambition said:


> After too much trial and error I have made it to this point.  I am finding a lot my tools are to small or too big according to what I need for the upscale.  This piece has been particularly tricky with mounting.   I started in the 4 jaw then managed a taper somehow, then straightened on the mill.   I think the correct way would be line bore.
> Then turned the undercut for the water jacket.  Some chatter marks for pushing the bore cut.  Do you change your cutter style when doing undercuts?
> Then onto rotary table after making centering disc for locating the bore. I must say me and my rotary table have a very love/hate relationship.  Locating ain't so bad but figuring how to mount is mind numbing lol.
> Was able to turn down and thread the face to 1/4 20.  Hopefully the scale works out.  I haven't made the head yet. And topped it off a little over for finishingView attachment 104564
> ...


I had the same thought about making parts to print and all went well. The only part I had to fudge was the regulator arm...That part I found, to be a little fidgity but I was able to make it close to the print and then adjust a little here and there. It came out pretty well in the end.


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## Naiveambition (Oct 19, 2018)

Figured I would update where I'm at.  Was able to finish up the block machining except for bottom holes. i want to make a base out of welded steel to resemble economy hit and miss engines, plus 50$ just for the base in alum. 


Here's a veiw of the undercut and bore.  There's some chatter marks on my undercuts but should be ok. This was a hard part to turn in the lathe with the the off balance, I couldn't  get anywhere near the speed needed.

The bore went okish with cutter issues but using carbide in my homemade bar was as good as I can for now.  I have a 1.5 lap and flex hone on the way . The white marks you see are from my fingernail so that gives an idea of the roughness
. 

The rear view  and the cylinder ready my first ever shrink fit.  I've read another build log and followed his example for a .003 interference fit. So we'll find out how good I did or not
. 

Top view with water tank.  I chose square to avoid the undercut . I will make a bolt on top later on.


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## Naiveambition (Oct 27, 2018)

Todays work.   Started out cutting my pieces from 1/4 angle iron.  Welded up the bottom side   This pic is before I fully welded, and I'm ashamed to show that photo,!  Need to work on my welding
.   

Bottom finishing. There will be another base ring around the bottom for aesthetics .


Fly cutting the top after milling for flat surface. I'm happy with my fly cutter , after all my cutter issues , this one cuts great and leaves a nice finish
. 

And the part mostly finished.  Need to weld two more peices to cover front and above the radius.  This radius was made with a 1 1/2 inch pipe and cut a 90*angle out , welded and cut with a hacksaw . With the sides being angled 8*  finding a way to hold the work is a little interesting.   

And the shot that I will be staring at tonite, till I figure where to start next. I'm sure I'm like most others that stare or play with their work possibly overexcessivly.


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## jimsshop1 (Oct 28, 2018)

Nice job so far! I have built the Kersel model myself and also have a full size 2Hp Economy which I completely restored before I built the Kerzel. This restoration was a great help in understanding just how a hit -miss engine works. It usually starts with 2 or 3 turns of the flywheels. The design and construction of both are very similar. Building on a larger scale should make building some of the smaller parts a lot less fidgety. I'll be following along as I want to build a larger scale engine also.

Jim in Pa


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## Brian Rupnow (Oct 28, 2018)

A very nice size of engine to build is the Odds and Ends hit and miss engine by Philip Duclos. If you want to see a picture of the two models (Odds and ends and Kerzel), look in my Dragsaw thread and there is a 3d cad of the two models side by side.---Brian


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## jimsshop1 (Oct 28, 2018)

Stupid search function won't work for me.


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## Brian Rupnow (Oct 28, 2018)

See post #14
https://www.homemodelenginemachinist.com/threads/building-a-model-drag-saw.30432/


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## jimsshop1 (Oct 29, 2018)

Hi Brian,

Can you please lead me to Philip's plans for the odds and ends engine?
Search does not work for me. Thank you.

Jim


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## Cogsy (Oct 30, 2018)

jimsshop1 said:


> Hi Brian,
> 
> Can you please lead me to Philip's plans for the odds and ends engine?
> Search does not work for me. Thank you.
> ...


The plans for that engine (and I think 3 others) plus construction details as well to the best of my knowledge, can be found in the book The Shop Wisdom of Philip Duclos. They're not freely available but I think the book is fairly cheap considering what you get in it.


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## Brian Rupnow (Oct 30, 2018)

Those plans are in a book--"The Shop Wisdom of Philip Duclos" available from Village Press.


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## jimsshop1 (Oct 30, 2018)

Thank you both. I will get one ordered!

Jim


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## Brian Rupnow (Oct 30, 2018)

Jim--I sent you a private message.


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## Naiveambition (Nov 4, 2018)

well had some terrible luck this week, as I ve been waiting for my parts to arrive. Fedx conveniently delivered my honing supply's to the guys down the street, after a reorder the neighbors brought it to my door a week later.    
So feeling all excited I get prepped up for my press fit.  So I put the body in the oven at 450 for an hr. Cylinder in freezer for 2 hrs.
   I Was still excited at this point mind you,   Lined up cylinder and a small tap with dead blow And now is "exceptionally stuck " about an inch in the bore. 
My only thoughts here is to try a press for removal and  turn a smaller diameter to lessen the amount of press fit on the rear.  I have seen a couple examples of this on other large engines but the Kerzel does not show this feature, but may not be needed in the original size.    Or cut it off and bore the stuck piece out again and remake the cylinder and save the block.


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## Brian Rupnow (Nov 4, 2018)

Been there---Done that. When I built my Kerzel I was very careful to machine everything to exact specifications. I started assembly with my  bench vice, and everything slid together except for the last half inch. There was no way in Hell my bench vice was  going to get it to move that last half inch.  At that point I figured I had nothing to lose, so I got my 6 pound hammer and ran over to the anvil. WHACK-WHACK-WHACK and it slid into place. That worked.


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## kvom (Nov 4, 2018)

Press should do it, but one suggestion for a redo is to pack the cylinder in dry ice.  Much colder than freezer.

Or just use loctite.


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## Brian Rupnow (Nov 4, 2018)

Your biggest trick now is going to be getting it "unstuck" to try again. I would make a "one of" custom puller and use a large flame from my oxy acetylene to heat everything until it pulled apart. Then mount the cylinder in the lathe on an expanding arbor and take the o.d. down at least 0.001" with 220 grit carborundum paper. Then coat it with high temp silicone or Loctite and try again.--Forget about heating and cooling the parts. Do it at room temperature, and have a big hammer and anvil close at hand. Machine a "driver" that fits into the end of the cylinder about 1/2" then has a shoulder on it so whacking it with the hammer doesn't distort the flange on the cylinder.


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## Naiveambition (Nov 4, 2018)

I did make a boss that fits inside the cylinder. The inner flange is small, so tommorow I'm gonna track down somebody with a press.  But sitting here thinking ,   when using a press fit do you account for round work. So if a .003 interference is needed, it would be.0015 each side like turning.?
I have 1.897 bore and 1.899 liner
Also Brian,  do you have a link for the plans you redrew for this engine.?


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## Brian Rupnow (Nov 4, 2018)

I just checked, and yes, there is a zip file I made when I built the engine in 2010. The bad news is the zip file contains only Solidworks files, so unless you have 2010 or newer solidworks software, you won't be able to open them. I will post the link here, but it's a big, big file, and if you don't have the software, it will just take up a lot of space on your computer. I will come back in a minute or so and post a link to my forum thread on building this engine.---Brian
http://www.mediafire.com/file/h9k09y5brk393h3/KERZEL.zip/file


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## Brian Rupnow (Nov 4, 2018)

This link will take you to my build on the forum.---Brian
https://www.homemodelenginemachinist.com/threads/brian-builds-the-kerzel-hit-and-miss-i-c.10091/


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## kvom (Nov 5, 2018)

Here are the plans:

http://www.floridaame.org/Plans/HHM1/HHM1-Complete Engine Model.pdf


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## Naiveambition (Nov 5, 2018)

Ahhhh. Crisis averted and the grey matter in my head is to returning the rightful place!!     The cylinder is pressed in and honed. 


  Went to the local Kubota tractor dealer for a press removal. Went rather easy and also noticed I was not straight in bore line, which is most of my issue.  
If I had access to a bigger press I think it would go as built , but lacking that, I chose to limit the pressed area to just beyond the water jacket and turned the rest to a very close fit.  So tight it took a couple minutes wiggling just the right way to move till the interference.  I ended keeping the .003+ Fit for the head end and dropped to .002 and rest was at 0.1-
This will mean I need to address the rear oiler so I don't have uneccasary oil leaks.      
After pressing using the vise, I was wanting to bring down the roughness level inside the cylinder and get the size for lapping. After removing the machining marks it looked pretty well done , so crosshatched and called it a day.


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## Naiveambition (Nov 6, 2018)

After feeling good about the days progress and gleaming a little, I just couldn't accept not knowing if the bore was straight. I had noticed after flex honing that I was still a little undersized. 
 So set up in the lathe around 150 rpm. Took about 4 passes to feel a Cutting force but ended up spot on at 1.5 The mounting remained loose to self align and the blocks were to keep it from turning.   Most examples is see of lapping are hand held, and I didn't feel comfortable if it locked up being such a cumbersome piece.  Afterwards ran the flexhone for about 15 seconds and I am gleaming again.


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## Naiveambition (Nov 9, 2018)

I thought I took more pics but can't seem to find em all.   Was able to put in a full day today and made some decent progress.    First up was the pillow blocks for the crank.  Started with the layout and used the rotary table to get radius on them and the caps also.     I made the caps as one, and split with a slitting saw.   The bottom block is pretty straight forward , I've only drilled a 3/8 hole and reamed for a locating hole in later operations
.


Most of today was finish welding and drilling holes on the base. I'm pretty happy with the part except for the welding cosmetics.  I really need to practice my welding.  In hindsight I would widen the base a little to accommodate the bearing block screws.  I had to make step blocks to weld in about 3/4 inch long to get a flat big enough to accommodate a 1/4-20 bolt head.


Here's where I'm at so far




And a teaser pic with the flywheels gives a relative size. The micrometer is 8 inch. The finished base is 4.4x 9.5 inch and weighs prob good 10 pounds. Flywheels are 7 inch. I'm guessing at least 30, maybe 40 pounds when done , so may help it sit still when it kicks


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## Aerostar55 (Nov 9, 2018)

Naiveambition said:


> View attachment 104830
> 
> Figured I would update where I'm at.  Was able to finish up the block machining except for bottom holes. i want to make a base out of welded steel to resemble economy hit and miss engines, plus 50$ just for the base in alum.
> View attachment 104831
> ...


Looking good


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## Aerostar55 (Nov 9, 2018)

Cogsy said:


> The plans for that engine (and I think 3 others) plus construction details as well to the best of my knowledge, can be found in the book The Shop Wisdom of Philip Duclos. They're not freely available but I think the book is fairly cheap considering what you get in it.


You can order the Philip Duclos book from Home Shop Machinist magazine.  The book has drawings for five IC engines and very good black and white photos of each operation with descriptive text. Making a small crankshaft out of bar steel, cutting gears using a mill etc.  I refer back to my copy often.  Usually sells for about $40USD !


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## Aerostar55 (Nov 9, 2018)

Naiveambition said:


> Trying to draw up the head for the Kerzel tonite, and need some modeler wisdom.  2 issues hoping to resolve
> 
> In the drawing  for the valve cage holes (lines a& b) how do I know the angle distance between the holes --- 360/ by 3?
> I see the radius of .219 for the hole layout but not a measurement for the moon shaped one.
> ...


The angle for the valves and spark plug holes appears to be 120 degrees the “half moon” shape would have to be just large enough to seat the base of the spark plug gasket.  It would vary somewhat according to which plug you choose.  I think Dave made his own plug.  Finally, 45 degrees is the standard valve seat angle.


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## Naiveambition (Nov 13, 2018)

Thanks for the replys everyone.    Not a whole lot this week, but was able to get the cylinder lined up with the bearing caps.


 After my first fitting, it became apparent that I messed up somewhere by.041  My guess is the bore centering, so I needed to bring the cylinder in line with the crank. So I skimmed .041off the bottom of the block.    I had a bar of delrin (I think), that was the exact size and straight to fit the bore.  I reamed a 3/8 centered cross hole that matched a reamed hole in the bearing blocks and inserted a punch to find my spot and tighten. Now my shim is down to .002 from..045.   
Well that's it for now, off to drink coffee and watch the news.


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## Naiveambition (Nov 21, 2018)

Well I've spent the last week trying and trying to make a suitable boring bar.   I've done research and am no closer to grinding my own bits!!   Finally resorted to a carbide bit with a triangle shape with a flat face and am getting a better finish for boring.
So after a nite setting up I was ready to start the line boring today. Getting to my first smooth cut was the hardest part so far. But after the initial learning curve I am now running smooth.   Adjustment are a little cumbersome having to stop and measure each cutter movement.  Bore measurement is not readable unless I remove the bar, so the last few thousands are gonna be rough.   
the brain is not working 100% at 3 am, so will wait for tommorow to finish the final cuts


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## Naiveambition (Nov 22, 2018)

Finished up the bearing block bores.  Wasn't a 100% victory but close,   I had a little more flex than I would of liked during the cut. I didn't have anymore holdowns that would work so I just went.005 infeed till I got to .9995. Was happy till the before final cut,  it ended up about .002 which is .001 cut , that chattered on one block.  I knew I should of taken it out the previous pass being a carbide tip.  may finish with a lap to clean up a little ,although  as you can't see it and being so close to being oversize I may pass. The first pic is the chattered one and 2nd is the nicer one.





One question though,  on boring bars the flex needs taken out with non-feed multi passes at the end,  are line boring bars the same?  If so how do you get back to the start with out the cutter gouging the work on the return?


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## Naiveambition (Nov 27, 2018)

After a disappointing week of designing the crank webs (is it webs or cheeks) to fit the metal on hand, I felt they were to wimpy looking on the engine.  Even though I only took out .120 of they just feel too skinny for this brutish looking engine
.




While I am waiting on the bearing bronze to arrive I decided to tackle one of the chores.  I would prefer not to have modern fasteners showing for an older engine, so am now making 10 1/4-20 studs. 
I sized to thread limits plus a little for stainless. Around .245 gave nice threads. Chucked up in the lathe and power tapped with the tail stock pressed up against the backside of the tap holder and the arm resting on the compound.  Was surprisingly easy as me and stainless have our issues when hand tapping.
Then flipped around and made a split collet (kinda)to grip the middle section and kept having issues with it spinning in the collet. So in a stroke of genius moment I took some 240 lapping compound and dabbed a little on the shank,   After this I was able to power tap the other side.  So now that the process is down, nine more to go


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## Naiveambition (Mar 26, 2019)

Finally able to return to the Kerzel.   I spent a good while building Harold halls grinding rest, and a qctp, so as I've been busy not so much for for fun. 

So first up was the crank,  this peice really needs  made from bar stock vs. a built up one.  The problem I've found is the bearing guides on the webs, they overlap the main shaft. And with this setup I've seen no way yet to assemble and have the webs in place.    Here I used a tight press fit on the top and a very close fit on the main shaft, to ease the pressing requirements.
Tommorow I will try to mill out the center, leaving enough to file and shape the rest.  
 I used a step drill and 15/64 to drill the hole, and made 303 stainless pins at .003 oversize for a press fit.   Used a vice to press pins and some creative positioning to have them proud.  Milled excess away very close then finished with a file.   I did notice that I spent the afternoon working and it looks just the same as when I started. Lol.


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## Naiveambition (Apr 2, 2019)

First up was making sure the webs ran true to the shaft and square with the bearings.  


I then milled out the center leaving enough to finish filing out the bearing diameters.  Earlier I had turned a alum spacer to the same diameter as the bearing blocks. I used this to gauge the press fit,and later ,use it for a filing guide .  





The plans call for a bearing flange on the main shaft,  again this causes issues with a built up crank.  I don't really have a good way to measure runout yet and with minimal runtime expected , I may just go with it,  or try to make flange by pinning and grinding to size, haven't decided yet.


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## Naiveambition (Apr 10, 2019)

Tonites work was getting the main bearing to fit.   I had purposely left oversize flanges not knowing the exact measurements.  Don't know if I messed up or the plans were incorrect.  But this is a custom build sooo,,,,  moving on!!

The plans call for a .030 flange and I felt this may be a little thin.  So went ahead and turned a recess to use the flanges .24 thickness with .030 proud to provide the clearance for the crank. Or at x2 size .60 clearance.




This was really my first time using a faceplate. After spending a good while trying to get it mounted and centered, the job went pretty well.  Now I need a new set of clamps that are more user friendly, both size and safety wise.  Balanced the wheel with strip magnets along the outer face and an extra pin . Without these, the job would of danced right onto the floor





Fitting to the caps was next .  Astonishingly they mate with just enough interference so that when the caps are tightend they are held in place firmly.  And I could take any out of roundness out with the reamer later.   Thentried out an adj. reamer.  For the record the Internet directions I found were obviously vague.  They say to just tighten them up to size by turning both nuts torwards each other. Well tried that and was getting nowhere near my target. After almost giving up and calling it junk from eBay for 10$. Somehow the seas parted and I found out that, the farther up the shaft you put the blades  gives the large dimension changes and when tight use the nuts for fine adjustment.  




Final was fitting of the crank. They are still a pretty tight fit right now , I can spin it but not freely yet.  
Feels like a milestone reached though


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## Naiveambition (Apr 16, 2019)

I've spent the last week off and on working out the fitting of the crank, and slowly progress is being achieved. 
I didn't have a good way to measure runout after machining , so tried to use the engine itself. And while I could get to .003 runout revolutionary, it was terrible axially.    On one side it was .003 and .011 on the other, with .oo3 between planes. 
Luckily I had bought two12 inch  3/4 ground stress proof rods , and when I cut off the crank journal I had enough left over to finish the main shaft from one 12 inch  peice.  After going off and building other side projects , I had forgot this bar was ready for install.  Well, somehow I installed the second bar , and didn't realize until I needed a known straight bar that I had this one centerdrilled and chamfered. Note to self , Write Stuff Down
Well in between 2-3 days of fitting, I had ordered a set of matched v blocks I completely forgot about.  I kinda wish they came a day earlier since I spent all day prepping a new crank from solid at 1.5x3x9. So a good chunk of metal.  
 Then my v blocks show up. So just for giggles I wanted to check the old crank, and at first I was getting the same reading as when using the motor.  So used the vise and gave her a little squeeze on the bottom of the webs , pushing together, and threw it back in the v blocks. And to my amazement I am dead nuts on at zero axially and less the .001 on the other.




   I mean I was so amazed that I kept asking myself , did I really get it perfect, maybe I am not measuring correctly , and of course,  just stare at it for minutes trying to find what I did wrong to get a perfect measurement. So maybe by the end of the day it maybe it will sink in that my starrett guage IS correct and I did the job right for once.


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## Naiveambition (Apr 25, 2019)

Today's work involved grinding to od of piston to size.     I bought a toolpost grinder for the 7x10 HF lathe, and decided to use it on my south bend also. 
  The centerlines are different between the two so I needed to make a adapter plate, and a rise of 3/4 inch.  When mounted In the toolpost it is way above center.    Also with the mounting between the SB and tp grinder it was less than friendly, to say the least. 
After making a first plate with a squeeze fit I could never get it tight enough to stop moving.  Without knowing the locating pin in the compound slide was spinning barely I made another one.  So after slaving all afternoon I was able to finally get it mounted tight. Luckily I I had enough room to get one stud bolt that mounts in the crossslide channel. I spent in total about three afternoons on this mounting after becoming flustered each time with different issues. Soon as I got the mount down all was easy as pie.    
 After setting up a diamond dresser c clamped to the chuck, i faced the grinding wheel.  Put lathe in slowest back gear about 50 rpm I think. Took four passes at .001 to reach 1.5.  Test fit to the cylinder and if my measurements are correct, it is at  -.001 or .0005 between cylinder wall and piston .  I couldn't find any other info besides lapping to fit the bore, so I hope this will hold compression.  I've never made a ic piston so wee will see.
As for the grinder it does feel a little underpowered and I was expecting a little better finish.  Granted this is one of my best finishes to date, so I'm pleased but,    as you can see in the pics it is a very light finish issue.  May be flex somewhere,? 
If any one had pointers please post them.


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## Cogsy (Apr 25, 2019)

I may have missed it somewhere, but why did you need to grind the piston rather than just turn it to size? I don't think I've seen a piston made this way before. It should work I guess but it's unusual so I'm curious.


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## Brian Rupnow (Apr 25, 2019)

I have never seen anybody grind a piston as you have done. I have always thought it would be nice to have a set-up for grinding the face of valves, but grinding a piston seems very strange to me.---Brian


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## Naiveambition (Apr 25, 2019)

The instructions call on a od lapp to size the piston.   Kerzel states to lap until piston will enter bore with slight resistance.  
At double size my piston is 2.5 inches long and 1.5 round.   That is a huge lap  I don't care to buy or make.   
But you guys are correct, I believe it was probably unneeded , since in theory it should not touch the walls throughout the stroke.  I was working with some small two cycles lately and noticed theirs were super smooth also.  I know they are cast but essentially smooth so I adopted the thought.   
With this model I am really trying to ramp up my craftmanship .  And I am getting whooped in the backfield sometimes,  but when I'm done with this I can move up the scale to my ultimate goal of a v8. Most of the operations are the same just a larger scale.


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## johwen (May 7, 2019)

Brian Rupnow said:


> I have never seen anybody grind a piston as you have done. I have always thought it would be nice to have a set-up for grinding the face of valves, but grinding a piston seems very strange to me.---Brian



(johwen here)  Before CNC when reconditioning engines for the auto industry pistons were ground as they were not round but ground with extra clearance across the gudgeon pin axis to prevent seizure. Special grinders were made for the job and a variety of master profiles was supplied to vary these clearance dependent on piston design. Yes grinding pistons even aluminum pistons was common however in the case of models you're correct. Cheers John


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