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Press in bushing? What should I use?

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buzzypeterson

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I have an aluminum tube that I need to put a bushing in. My first thought was to just drill it to the next size and hysol a cut tube as a bushing but I need it to be real solid. So I need some opinions, I have heard of swaged bushings and joe bolts but can't find much info on them. I don't want it to be threaded just a regular bushing, the bottom (blind side) (inside of the tube) needs to be flush.
 

Dana

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What are the dimensions, and what is the bushing doing?

Dana
 

Angusnofangus

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I have an aluminum tube that I need to put a bushing in. My first thought was to just drill it to the next size and hysol a cut tube as a bushing but I need it to be real solid. So I need some opinions, I have heard of swaged bushings and joe bolts but can't find much info on them. I don't want it to be threaded just a regular bushing, the bottom (blind side) (inside of the tube) needs to be flush.
FYI: Joe-Bolts are high strength blind fasteners.
 

buzzypeterson

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Not sure if my picture will load here. It's a folding wing, the front doesn't carry a ton of load but that's where we are ovaled out, no way I'm putting my butt in the air till we figure something out. the front spar tube where it's just a pin that holds the wing. I think the previous owner drilled it like that. I'd go one size bigger hole and bolt if I could, there is plenty of room on the spar but the fuselage fitting won't allow that. I've thought about sleeving the OD but There's not a ton of room before that first rib so I don't picture a little stub on the OD carrying a load. It's just a 280 lbs ultralight not an F16. I know the best answer is a new spar but that ain't happening. Picture is of wing open, In sure you get that it ramps up onto the fuselage fitting then gets pinned
 

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Mad MAC

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While initially looking like a real pain in the ass approach, I would suggest a couple of aluminum top hat bushes (what is the current spar material installed with epoxy from the inside of the tube and then trim the steel tube down to give clearance thus the two mating surfaces easier to make flat and parallel.
 
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Dana

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So what are the dimensions? Looks like around 2.5" diameter spar tube?

Get a piece of tubing that's at least as thick wall as the existing spar. If you're lucky and you can find a slip fit size, great (.058 wall, for example, will accept an insert 1/8" smaller diameter). If not, get a piece as close as possible, preferably with an OD slightly larger than the spar ID, 4-6" long. Slit the tube, now you can squeeze it down so it's a tight fit. The slit should be away from the eventual bolt holes, of course. Slip it in, drill and install a few pop rivets to hold it in place, some epoxy too won't hurt to keep things solid. Then simply drill the new holes through the sleeve, shorten the bushing on the fuselage tube as required, and you're good to go.

I did repairs like that on an early Quicksilver I once owned (not the wing spars, but the same idea). Many people installed sleeves like this before the holes ovaled out, as a preventative measure.

Dana
 

Turd Ferguson

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It's a folding wing, the front doesn't carry a ton of load but that's where we are ovaled out, no way I'm putting my butt in the air till we figure something out. the front spar tube where it's just a pin that holds the wing.
I think the previous owner drilled it like that. I'd go one size bigger hole and bolt if I could, there is plenty of room on the spar but the fuselage fitting won't allow that.
I've thought about sleeving the OD but
There's not a ton of room before that first rib so I don't picture a little stub on the OD carrying a load. Picture is of wing open, In sure you get that it ramps up onto the fuselage fitting then gets pinned
That's what I'd do Buzzy, I'd put a shrink fit sleeve around the outside (OD) of the existing spar tube, secure it with some type of fasteners (like AN bolts), then carefully drill new holes. The sleeve will have to be securely fastened to the existing spar tube or you're gonna have trouble. You can make the sleeve wider, just notch out for that first rib. I'd also make the sleeve with as much wall thickness as possible, more bearing area will prevent a recurrence or at least slow it down. You'll have to get a longer pin but no big deal. (Actually what I would probably do is turn a sleeve on my lathe)

Have to be careful not to change the geometry of the attachment or you'll end up with different incidence and/or wing twist which will affect the flying qualities.

Is the bottom hole the one that's wallowed out? How bad is it?
 

proppastie

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using standard aircraft 4130 tubing same wall as fuselage fitting bushing. drill or ream and press into spar wall between head of bolt and fuselage fitting,....also between nut and fitting on other end. the bushing will only be as long as the wall thickness of the spar. because it is steel and captured you should not have any problems. Fender washers would not hurt under the head of the bold and nut.
 
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buzzypeterson

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That's a steel ramp inside. So unless I remove the ramps I can't do anything inside. So the outside sleeve is about all I got as an option. That last answer I don't understand, the one with the bolt. Can you maybe break it down a little more simple for me?
 

Turd Ferguson

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using standard aircraft 4130 tubing same wall as fuselage fitting bushing. drill or ream and press into spar wall between head of bolt and fuselage fitting,....also between nut and fitting on other end. the bushing will only be as long as the wall thickness of the spar. because it is steel and captured you should not have any problems. Fender washers would not hurt under the head of the bold and nut.
that last answer I don't understand, the one with the bolt. Can you maybe break it down a little more simple for me?
I think pastie is thinking there is a bolt that fastens the spar to the airframe when in fact it's only a pin.

A bushing where the length is equal to spar tube wall thickness (~.100") will likely work loose and/or fall out in short order. That's what I was saying, whatever you use, even the OD sleeve needs to be securely attached.
 

proppastie

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That's a steel ramp inside. So unless I remove the ramps I can't do anything inside. So the outside sleeve is about all I got as an option. That last answer I don't understand, the one with the bolt. Can you maybe break it down a little more simple for me?
BUSHING.2JPG.jpg
You need a bolt not a pin
 

proppastie

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I believe you can also get oversize bolts or pins .010 I think, not sure about the size. I know there are also tapered pins you would need a tapered reamer. You could turn down a larger pin to say .010 oversize, I assume that should take care of the problem, do not want to go too big but that is only .005 on a side. Buy a ream to what ever size you decide on they are not that expensive. Go to McMaster Carr.

I recommend that you clamp this tight with a nut......which will depend on if there are oversize bolts tapered pin or if you use the bushing idea,......good luck
 
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