Yoke Bushings / side windows / headliner.

[Tom G]

Hello Everyone: Its been a while since I've posted on here but I have a few issues that I need to address and need some help with.

First I need to do something about the yoke bushings in my plane. I'm tired of hearing that horrible squeak from the panel when i do a pre-flight and its definitely time to do something about it. Fortunately my cousin also flies the plane and is much more knowledgeable and patient with such matters. We have both looked at it though and it seems like the bushings are there and when you reach behind the panel you can center the bushing but it slides up and down and there doesn't seem to be any way to firmly position it in the center. Is there a way to fix it in position to center the column through the hole in the panel? Does the bushing need replacement? Are they available?

Secondly, I replaced the side windows in my plane decades ago and used plexiglass that was too thin. They work ok but the two Acco paper clamps with the elastic between them that keep the right side window from vibrating open in flight are really low rent and its definitely time to eliminate that effective but somewhat cheesy looking solution to the problem. Does anyone know the proper thickness for the sliding side windows in the BC-12-D? Also I was wondering if anyone might happen to have to proper dimensions for the windows?

Lastly any tips on installation and the best place to obtain a replacement headliner would be appreciated. The current headliner was installed in the mid nineties when the plane was restored and at the time the fuselage was not covered. Its the standard kind with the bows and no quarter windows.

Thanks to all in advance!!!

Tom Gilbertson

[astjp2]

Re: Yoke Bushings / side windows / headliner.

You need to have the yoke shafts replated and new phenolic bushings made...that along with new ball bearing pulleys and the airplane will be better than new. You can make them yourself Or have someone make them for you. I used .250 thick and just cut it to size and bore a 3/4" hole in it, then slowly enlarge the hole with a flapper sanding wheel until the shaft glides through smoothly....took me a few hours to do but I am anal about such things. Windows are 1/8" but .100 will work. I use acrylic, it does not have some of the issues like lexan if you have wing tanks. Tim

[M Towsley]

Re: Yoke Bushings / side windows / headliner.

To go along with the bushings, use a small amount of liquid graphite on the shafts.

[Tom G]

Re: Yoke Bushings / side windows / headliner.

Thanks Tim and Marty, actually the control shafts themselves are in very good shape and appear to be chrome plated. The squeak comes from the shaft hitting the instrument panel. The bushings appear that they would work if they were positioned right. It feels like they are in this sliding channel which is attached to the back of the instrument panel but there just isn't any way of securing them in place.

[3Dreaming]

Re: Yoke Bushings / side windows / headliner.

I just looked at a fuselage here to confirm my memory. There should be a long 6/32 screw that goes across from channel to channel under and above the bushing block to keep it in place. take a look behind the panel and see if it is there. If not you will need to install one, at least on the bottom side. If it is there you might be able to slip a piece of plastic tubing around the screw raising the block just a little to keep it from rubbing.

For the head liner you can buy one from Airtex, or if yours fits OK take it out to a antique car upholsterer and have them make you a new one out of wool broadcloth.

[Robert Lees]

Re: Yoke Bushings / side windows / headliner.

I think the bushings have a C- (or half-square) section rubber strip to secure them into the channel. If the rubber has perished, then there is nothing to stop them sliding up and down.

Something like this which is for 1/4 inch thick material.

You still need to remove the instrument panel to fit, so it would be worth making new bushings anyway, as Tim (astjp2) suggests.

There is a long threaded screw that lies horizontally above the bushing, and it pulls the two steel retaining C-sections together, so clamping it all together...perhaps they are missing or have stripped threads? I'll see if I can find a photo.

When I made new bushings about 22 years ago, I made them out of oil-impregnated nylon (trademarked Oilon ) which has self-lubricating qualities. I also installed polished stainless steel tubes for the control columns, but whether you'd get that past a US IA I dunno!

[Scott]

Re: Yoke Bushings / side windows / headliner.

Thanks Tim and Marty, actually the control shafts themselves are in very good shape and appear to be chrome plated. The squeak comes from the shaft hitting the instrument panel. The bushings appear that they would work if they were positioned right. It feels like they are in this sliding channel which is attached to the back of the instrument panel but there just isn't any way of securing them in place.

the bushing blocks should not move. they are supposed to be "shimmed" in place with strips of rubber or possibly wood. There should be rubber U channel covering the four edges, the shims go inside the channels as necessary to position and hold the block in place. I think you really need to remove the instrument panel to do it right.

https://4.bp.blogspot.com/-IhGeJBFLeyg/VhGKVOttDHI/AAAAAAAABzE/y7tYyIjUHCI/s1600/DSCN3775.JPG

[astjp2]

Re: Yoke Bushings / side windows / headliner.

That rubber channel can be bought in the states from Metro moulded products

https://www.metrommp.com/index.cfm?f=part_list_by_type&Type=U%2DChannels

I ordered about a foot of 3 different kids and tried them until I found one that fit.

They also carry the header tank fuel grommet that goes under the gas cap, you just need to trim some of the ribs out from the bottom if you need the clearance.

https://www.metrommp.com/index.cfm?f=type_detail&ModelNumber=GF%2022&Type=Grommets%20-%20Gas%20Filler

Tim

[Robert Lees]

Re: Yoke Bushings / side windows / headliner.

OK, I found a picture. There's a bolt top and bottom to minimise the up-and-down movement. The green colour is the as-supplied colour of the oilon, but similar products (or even plain nylon) are available in black.

[Robert Lees]

Re: Yoke Bushings / side windows / headliner.

Crossed with the above couple of posts...we're all singing from the same hymn sheet!

[PA1195]

Re: Yoke Bushings / side windows / headliner.

The top of my control panel lifts off after removing screws along the edge closest to the pilot. I can reach behind and deal with things. Tom can you get to yours as easily?

I have soft tough white UHMW polyethylene about 1/4' thick for my bushings that was installed prior to my owning. Might be another option as it's easy to cut, drill, and trim.

Gary

[3Dreaming]

Re: Yoke Bushings / side windows / headliner.

Tom can you get to yours as easily? Gary

I don't think so. I think I would need to remove the control wheels, remove the instrument screw, and then remove the panel.

[PA1195]

Re: Yoke Bushings / side windows / headliner.

I don't think so. I think I would need to remove the control wheels, remove the instrument screw, and then remove the panel.

The forward edge of my one piece aluminum top panel cover over the tank and instruments underneath just rests on the lower inside window trim. The rear (facing the pilot) screws to the top of the vertical instrument and control panel. So maybe it's different than most? Very easy to inspect and service the electronics, controls, and instruments.

Gary

[Hank Jarrett]

Re: Yoke Bushings / side windows / headliner.

It is a LOT easier to take the whole wheel and shaft out by removing the shaft from the universal at the front. Getting the wheel off of the shaft is NOT easy since it is supposed to be attached with a tapered pin. Pulling the bolt holding the universal to the shaft is easy except for getting your head and shoulders in the foot well. People when these planes were built were a lot smaller than we are now!

A good antique car upholsterer is the way to go for putting in your new headlinner. Let HIM take the old one out. You learn a LOT about how it fits and what order to attach things by removing them. He will also want to use the old one for a pattern for the new one. If you start by slashing the old one it will be a LOT more work! At least let him make the decision as to who should pull the old one.

[M Towsley]

Re: Yoke Bushings / side windows / headliner.

Gary, this will be a little off-track but the glare shield was made of a black-covered cardboard, as well as the kick panel underneath the front of the seat. It is actually rear window shelf used in cars years ago and can still be obtained from an upholstery dealer. It is lighter than aluminum and I have never had problems with it, even when it got puked on.

The front should go in a rubber channel that is no longer commercially available, though someone had some made years ago. That channel installed on the bottom of the windshield and then there was a lip that contained the cardboard shelf material. At the front, (rear), there are maybe five screws that screw down onto the top edge of the instrument panel to hold the glare panel. If you don't have the rubber lip material the cardboard doesn't mar the windshield from vibration like aluminum would. (Mine originally came with aluminum, etc. But, when I installed the new instrument panel I utilized the black cardboard material).