Counter-rotating props - Type A midget sub project

[boomerfunker]

I'm trying to come up with a way to counter-rotate two inline screws on a single shaft like existed on the real Japanese WWII subs. Does anybody have a brilliant idea they can share with me? I would appreciate any feedback, Thanks

Tom

[dietzer]

All you need are two

All you need are two identical gears, one long shaft and one shorter shaft. The long shaft is driven by the motor, and has one gear on it. The shorter shaft just has the other gear on it. This will cause the two shafts to counter-rotate with the same RPMs.

This approach does mean, however, that the motor is not on the centerline of the boat. If you need the motor to be on the boat's centerline, put a pinion gear (of the same pitch as the other gears) on the motor and position it so that the motor engages one (or both) of the gears on the prop shafts. Adding a pinion gear means you can pick a smaller gear, and therefore get gear reduction and counter-rotation.

Hope this helps,

Carl

[bob the builder]

How's this?]http://www.subcommittee.com/forum/MiKea1.jpg

For info on that

How's this?]http://www.subcommittee.com/forum/MiKea1.jpg[/img]

For info on that picture, click here

[dietzer]

Tom,

Please disregard my earlier posting.

Tom,

Please disregard my earlier posting. For some reason I misread your post and thought you meant side by side rather than inline props. Sorry about that.

What Bob posted is the normal way to go for inline counter-rotating props on the same shaft.

Here's some more examples]1/20 scale Torpedo with Counter-rotating props[/url]

This site has 3 different solutions for counter-rotating props on the same shaft.

Carl



Edited By dietzer on 1095210184

[boomerfunker]

Thanks!! You guys are swell
It

Thanks!! You guys are swell
It was ticking around in my head an I was sure someone had done this. Off to the shop..