Elevator bellcrank bearing size

[U2fletch]

Cleaned up the paint from the inside of the bellcrank, then measured the overall width of the bellcrank, 35mm. The bearings are 5mm width, so needed a bushing 25mm in between which was solved with quick stop at the lathe. Before pressing in the bearings I measured them. Not even close. OD of the bearings are 5/8”, or 0.625”. The ID of the bellcrank is 0.614. Something is not right. I checked the parts bin for any other bearing that might be close, but came up empty.

Am hesitant to ream it out before checking as it does not seem like there will be a lot of metal left on the tube.

[Ryan Koeneke]

I used a Dremel with a sanding tube to clear the paint out and then carefully kept going around and around to ensure a good fit. I think others have done the same.

[U2fletch]

That’s reassuring. I just went back and looked at the wall thickness and it should be fine. I do have a 5/8” reamer which will work nicely.

[Steve W]

I did a couple of wings for a 5 place a few months ago. I just pressed the bearings in the bellcrank without any extra effort. Felt like a good pressed fit. Was there a run of parts that were an odd fit?

[U2fletch]

This was the elevator bellcrank. I have not opened up the wing kit yet, so I expect they are slightly different.

[Steve W]

My bad! Should have read it a little closer

[Utah5]

I have kit #31 and fought the same problem. I first sanded the paint off with a Dremel and pressed the bearings in as per Collin's instructions. This was way too tight and ruined the bearings. As I tried to take off more metal with a Dremel it was obvious that I wasn't going to be able to keep it in the same plane to prevent binding with rotation. I called Virgil to get new bearings and at the time, he wasn't aware of this being much of an issue for other builders. I ended up taking it to a friend's machine shop. He enlarged it on both sides of the bell crank to .625 at a depth of the bearing and in the same plane. My bearings measure .624. my tube wall is still .059 thick. I will prevent the bearings from rotating with some bushing locktite as advised by Virgil and my machinist friend. It it perfectly smoothe rotation now on the bearings. I hope this helps.

[TLyon]

I had this same issue on the aileron bell cranks, and ruined a set of bearings. Virgil offered to send new ones which I appreciate, but I’ve got to figure out how to get the bad ones out. How did you go about that?

[Utah5]

If I remember right, I removed the bolt in the center that held the sleeve centered between the bearings. This allowed the sleeve to move a little off center and expose a portion of the bearing on the opposite side. Then I too thin metal punch and used a vice to press the bearing out from the opposite side. I It was way too tight and completely destroyed one bearing. It seems that anything that required any significant force to press in would cause a significant restriction of movement while in the bell crank and mya slight cogwheel motion after it was removed n the bearing. So I basically ruined 4 bearings before I finally had it machined.

[TLyon]

Thanks, I should have gotten a follow-up posted the other day. I ended up doing the same thing for removal.

[N204jh]

Cleaned up the paint from the inside of the bellcrank, then measured the overall width of the bellcrank, 35mm. The bearings are 5mm width, so needed a bushing 25mm in between which was solved with quick stop at the lathe. Before pressing in the bearings I measured them. Not even close. OD of the bearings are 5/8”, or 0.625”. The ID of the bellcrank is 0.614. Something is not right. I checked the parts bin for any other bearing that might be close, but came up empty.

Am hesitant to ream it out before checking as it does not seem like there will be a lot of metal left on the tube.

Hey, Jeff and others, my BH5 kit didn’t come with the elevator bellcrank bushing and I’m hesitant to install without it. Jeff, did your kit come with it and you lathed it to precise length / width, or did you fab it completely?

What about others that have kits they received in the last 2 years, did you receive the elevator bellcrank bushing? If so, did you have to modify it to fit?

Virgil said it wasn’t really needed, but I worry about the bearings being held by the tiny inside ridge.

Thanks, John

[U2fletch]

I referenced the plans and turned them out of some steel rod in my scrap bin on my lathe. They are 0.25" wide. 3/16" ID and 0.28" OD if I recall. They are the ones for between the elevator halves in the tail, correct?

[N204jh]

No, the elevator bellcrank connected to the control stick. The bushing between the two bearings.

[U2fletch]

Sorry, that makes sense based on the OP. I made those from scrap. Did not have the pieces in the kit.

[dramsey]

Sanding the inside of the bellcrank with a dremmel until I got a good fit worked for me. You want to still have to press the bearing in the hole so its trial and error….sand a little try pressing in bearing, sand some more…. until it presses in snugly.