c00lduke

I was just thinking and i was wondering if the middle rotor has a stationary gear. I would think that it would have to but i cant imagine how they would mount it. I was just wondering if someone could post pics or just explain how that all works out.



Thanks

~Luke

RETed

Yes it does.





-Ted

c00lduke

of course you know this, the 13b the front and rear stationary gears bolt up through the front and back plates how does the stationary gear bolt up for the middle rotor on a 20b?

Jeff20B

It's on the 80mm thick plate.

c00lduke

yeah in the pics i've seen its pretty thick but how does it bolt though for the gear on one side but still be smooth on the other?

Jeff20B

Because the 120º offset of the rotors somehow works itself out. You have two rotors on one side of the thick plate and one on the other side. The two on one side are 240º of moving mass that match the 120º on the other side. Yes it is a bit offset if you think about the two rotors only being 240º out of a full 360º. It only needs one counterweight on the back of the engine to offset these two rotors.



Actually, I think the rear counterweight isn't a perfect 180º offset from the rear rotor like it always is on two rotor engines (and one rotor engines I guess). It's probably only 120º offset and relies on the middle rotor to offset the other 120º. Then the middle rotor is again just one 120º 'piece' of a 360º 'puzzle' where the other two rotors are the other 2/3rds of the 'puzzle' so to speak. Lastly, we get to the front rotor, and as you've probably already guessed, it is 120º offset from the middle rotor, thus leaving the front counterweight to be offset by another 120º, which completes a nice balanced rotating assembly.



Did any of that make any sense? I've never rebuilt a 20B, so this is the best my imagination could do.

Jeff20B

Oh, you were asking how the stationary gear bolts to the 80mm thick plate? Uh, I dunno.



Or were you asking how the shaft can fit on both sides of the gear and still be removable? The front section of shaft slides off of the main shaft for dissassembly. You need a puller.

c00lduke

mainly how it bolts up and still alows for the smooth side on the other side

Jeff20B

j9fd3s is going to weigh a 20B plate tomorrow. Maybe he'll take some time and see how the stationary gear is attatched.



Question: is this for some sort of custom three or four rotor engine where you machine a regular intermediate plate to accept a stationary gear? Is that why you're curious about this subject? The HITman would know who to talk to for more info about engines like that. Jeff Bruce makes E shafts for those types of engines.

RETed

Why don't you get one yourself and find out?





-Ted