Single Cylinder Opposed

Drilled, reamed, and installed the tapered pins and gave it a paint job.
The paint isn't very dry but I had to see if the crank would fit the block.
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It fits just fine.
Cut out 4 main bearing caps for tomorrow.
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Thanks for looking
Ray
 
For anybody who's interested, a good example of one of these engines that's accrued some real time and real miles in the real world is the Napier "Deltic" engine.

From some earlier conversation, this engine started life with the cylinders running in time with each other, but as time went on it was redesigned to have the exhaust piston run a bit late. I don't remember how much, but it's enough to make a "normal" engine mechanic cringe. But, this allowed two things- It kept the combustion chamber smaller, for longer, as one piston "chased" the other, which burned cleaner (which in industry, outside of consumer goods, means more of the fuel's energy went out as power, and not heat or soot), and second, it (Again, industry perfers NOT to watch their fuel investment go out in a cloud of smoke). These opposed piston engines, are truly fascinating. This one in particular is really the apex of where it went to before more modern methods took over.

A link to get you started if you're interested. And if you are interested, and you've already had your asprins today... the firing order is clickable......

 
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I got the main bearing caps installed and numbered so I won't get them mixed up.
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Over to the lathe with a drill bit first to get a large enough hole for the boring bar. My stack up looks precarious but it did work.

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Line boring to just under the size of the bearings. I will finish with an adjustable reamer on the bench.

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Thanks for looking
Ray
 
After some time reaming and adjusting it all worked out just fine. The crank does spin freely and fits in the block with about 0.005 wobble at the outer crank ends. That should be just fine.
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Connecting rod, lower piston and wrist pin.
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Assembled on the crank.
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Thanks for looking
Ray
 
What an interesting build. I need to search on these and learn more about them.
 
Thanks Tom


I started out with a 3" diameter aluminum bar and cut it down to 2.500 overall. Then I cut the center section down to 2" and bored the center out to 1.25 for the cast iron liner.
I have a garbage can full of aluminum strings.
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3/4" boring bar with a 7" stick out.
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Thanks for looking
Ray
 
I milled some index flats and drilled for the cylinder bolts.
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It even fit first time.
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I think that this engine is going to be rather tall.

Thanks for looking
Ray
 
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