Ruining a perfectly good engine

[Rickinlexky]

I always liked cutaway engines where you could see what was going on inside, but I can only work on a small scale, so I got an old model airplane engine.

I cut the threaded holes a little short of halfway so the threads would hold when assembled. I haven’t cut the cylinder sleeve because it’s hard cast iron, but I might go back to that later

 

[Rickinlexky]

And a smaller one to go with it

 

[woodchucker]

And a smaller one to go with it

I don't think your marked direction of rotation is correct.
Unless its a counter rotating engine.

 

[Rickinlexky]

No, it’s standard rotation, clockwise to the engine. A reed valve engine can run in either direction, but a rotary valve like this one can only run one way because of the valve timing: the valve is open as the piston rises so it sucks fuel into the crankcase, then closed as the piston descends so it can force the fuel from the crankcase into the combustion chamber without backfiring through the carburetor.

 

[Ulma Doctor]

I always liked cutaway models, they really take the guesswork out of what’s going on in the model.
Thanks for sharing

 

[Larry$]

Until I saw a cutawy of a radial I had no idea of they managed all the connecting rods.
Nice full scale cutaway at the air museum near Lincoln, NE
I always liked the A1H's that flew off the Ranger, while I was in the Navy (long ago!) Deck launch, no Cat needed. Big radial with electric blue "flames" on the prop tips during run up at night. They were antiques but still flying in the mid '60s.

 

[Rickinlexky]

Until I saw a cutawy of a radial I had no idea of they managed all the connecting rods.
Nice full scale cutaway at the air museum near Lincoln, NE
I always liked the A1H's that flew off the Ranger, while I was in the Navy (long ago!) Deck launch, no Cat needed. Big radial with electric blue "flames" on the prop tips during run up at night. They were antiques but still flying in the mid '60s.

I volunteer at an aviation museum in Lexington KY; we have a cutaway B-29 engine that gave me the idea to try doing these. We also have one of the first radials, a 1909 Gnome rotary (the engine spins with the prop). That one’s not cutaway, but I got to partly disassemble it while preparing it for display. Fascinating machine, and almost all of it was machined from nickel steel billet.

 

[ChazzC]

Now I have a reason to buy more stuff that doesn't work for display projects: thanks?


BTW, nice results.

 

[woodchucker]

No, it’s standard rotation, clockwise to the engine. A reed valve engine can run in either direction, but a rotary valve like this one can only run one way because of the valve timing: the valve is open as the piston rises so it sucks fuel into the crankcase, then closed as the piston descends so it can force the fuel from the crankcase into the combustion chamber without backfiring through the carburetor.

but you are showing counterclockwise, and most propellers are clockwise. There are special propellers for twin engine planes .

 

[woodchucker]

I volunteer at an aviation museum in Lexington KY; we have a cutaway B-29 engine that gave my the idea to try doing these. We also have one of the first radials, a 1909 Gnome rotary (the engine spins with the prop). That one’s not cutaway, but I got to partly disassemble it while preparing it for display. Fascinating machine, and almost all of it was machined from nickel steel billet.

I have seen that engine fly up at Old Rhinebeck Aerodrome in NY. You have to shut and start the magneto for landings. Quite a lot of concentration to do it right. I guess that's why so many flipped or ground looped.

edit: over the years, quite a number of the museum pieces have crashed. Mostly because those planes are more difficult than people think. Those pilots are quite good putting on regular shows with different aircraft. Great show for the kids.