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General control line discussion => Open Forum => Topic started by: Gary Dowler on September 23, 2018, 01:09:02 AM
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Ok, I'll try my best to describe this. Had to fix the pushrod connection to the bellcrank on an old plane. It's in my Cosmic Wind. Pushrod had become disconnected, and I don't know how it was originally attached. It appeared to be an easy fix, but has had a twist. The pushrod comes in under the bellcrank, makes a normal 90deg bend upward through the hole.
The problem is that when I attached the pushrod, the right side of the bellcrank hits the pushrod about half the time.
I need to do something to maintain a small gap between the horizontal pushrod and the bottom of the bellcrank to provide clearance for the bellcrank to go over it. Is there a clip of some sort that can do this? It's a short 2" bellcrank, but the plane flies actually quite well with it. I can change it but this means changing out the leadouts as well, and I'd rather avoid it if I can.
Gary
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I’m assuming that the 90 is bent so the end of the rod faces up I would suggest putting a very slight bend down bend in the pushrod so you have enough clearance. If the end of the rod faces down make it a up bend.
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Can you put another washer under the bellcrank?
While typing a response to you it suddenly hit me! I was thinking I'd have to solder a washer on the rod below the BC as suggested, then use a wheel lock collar on top because if I solder another washer on there, it's likely to loosen the bottom one.
What about using the lock collar below the BC, even if I have to grind it a little thinner. It won't go around the 90 at the bottom well anyway and should stay in placecwell. Then solder a washer at the top to secure the BC.
GARY
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I think that normally the L bend is secured just by the platform that the bellcrank mounts to. Making a 20 or 30* bend after the swing of the bellcrank to exit the top wingskin.
I was thinking wheel collar also, but because of the thickness, you might instead use a skinny nut? Even a plywood or a piece of printed circuit board would work, or a short piece of brass tube with a washer pre-soldered to that on top.
Or solder on the first washer at the 90*, add a couple or three more on top of that and then insert into the bellcrank?
R,
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