raym/rupinow vert hit & miss

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I was looking at the "weight" drawing and it is difficult for me to discern the actual lines of the part from the dimensional lines... is it possible to ask the computer to define the lines of one or the other on the drawing ?
Ray M
 

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Ray--Maybe this will help.---Brian
oj6t5G.jpg
 
They were in there mainly for set-up. I put an 0.063" pin in there to hold everything in correct alignment before I drilled the holes in the bracket and cylinder. The hole really doesn't have anything to do with the function of the engine.--Brian
 
upper bracket... kind of a tetchy part for me to make.


P1010813.JPG

in a vise on the mill

P1010818.JPG

in the vise on the mill... the vise turned 30degrees on the mill bed to pick up the angles
P1010820.JPG

in the rotary table on the mill

P1010822.JPG

please holler if any questions
Ray M
 
Good looking parts Ray. That bracket is a good example of something made for "pretty". It could have been a lot simpler, but it wouldn't have looked nearly as nice.---Brian
 
Good looking parts Ray. That bracket is a good example of something made for "pretty". It could have been a lot simpler, but it wouldn't have looked nearly as nice.---Brian
yes, truly a case where form doesn't follow function. I suppose the question of form and /or function must have come up often for a design engineer due to possible cost
implications.
One of my favorite examples of a 'form and function' design is my old Southbend 9 inch model 'a' lathe.
Ray M
 
Your making some good progress Ray. I also when I get to it:rolleyes: am going to have a go at making the rings which I have never done .
I have been saving a little bit of cast iron I have left over from another job that I got from Germany for making some rings as it seems
a better quality than what I have sourced locally of ebay.
Cheers
John
 
Looks like I have ~ 4.72:1 Compression Ratio with >.032 gaskets @ top and bottom of cyl. Am wondering how that compares with the original?
Looks like I can increase to ~5.5:1 by using .010 and .016 thick gaskets top and bottom...Also wondering what would be minimum CR for this engine to run properly?:rolleyes:

Ray M
 
Ray--I used .031" thick gasket under the cylinder and under the cylinder head. Engine ran just fine with that. I am not sure what you mean by minimum CR. I don't know what CR is.---Brian
 
Sorry Brian, here is a definition...
https://en.wikipedia.org/wiki/Compression_ratio

Do you have a feel for what the compression ratio is on your engine, possibly in your design notes?, or by checking the distance from top of piston @ TDC to cylinder deck with your computer aided design criteria or direct measurement?
Can anyone suggest a low end Compression Ratio on this type of engine?
I am wondering if I have made a mistake in dimensions and should possibly re-make some parts before continuing... looks like I can increase the CR to ~5.5:1 by decreasing gasket thickness to .o12 if need be.
Thanks
Ray M
 
Ray--For this type of engine compression ratio only needs to be 3.5:1 up to 5:1 The higher the compression ratio is, the less chance the engine will have of restarting after a series of misses. I believe the compression ratio of my engine is 4.5:1.--Brian
 
Thank you Brian... looks like my 4.7:1 is in line with yours, I didn't need to create a cavity in the head because of the type of spark plug used. I might use a .010 gasket on top cyl in order to increase the CR to 5:1.
Raym
 
RINGS... continued


heating with acetylene torch without direct flame contact with the rings
P1020002.JPG


'bout the color of a robins breast
P1020009.JPG

cleaning up the rough edges prior to final fit in the cyl (.003" gap)
P1020017.JPG


after de-burr and cleanup
P1020019.JPG


installed on piston
P1020020.JPG


cyl wall after thirty minute test run-in using external motor power
P1020028.JPG

Ray M
 

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