Kerzel hit&miss by Mike

[Cogsy]

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

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.

 

[Brian Rupnow]

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

 

[jimsshop1]

Thank you both. I will get one ordered!

Jim

 

[Brian Rupnow]

Jim--I sent you a private message.

 

[Naiveambition]

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.

 

[Brian Rupnow]

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.

 

[kvom]

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.

 

[Brian Rupnow]

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.

 

[Naiveambition]

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.?

 

[Brian Rupnow]

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

 

[Brian Rupnow]

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/

 

[kvom]

Here are the plans:

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

 

[Naiveambition]

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.

 

[Naiveambition]

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.

 

[Naiveambition]

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

 

[Aerostar55]

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
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.View attachment 104832
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
. View attachment 104833
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
. View attachment 104834
Top view with water tank. I chose square to avoid the undercut . I will make a bolt on top later on.

Looking good

 

[Aerostar55]

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 !

 

[Aerostar55]

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.
View attachment 102397
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
View attachment 102398

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.

 

[Naiveambition]

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.

 

[Naiveambition]

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