Cable thimble bushing

[TimHicks]

I'm about to make new aileron cables for my '46 BC-12D.
My old aileron cables had small, round, plastic inserts inside the thimbles.
When I ordered "Thimble Bushings" from Spruce, I got the little plastic things on the left which are clearly not the right part.
Any idea where I can get the round-bore thimble bushings? Or what they are called?

[Hal]

Re: Cable thimble bushing

Hi Tim,
See http://www.aircraft-spruce.com/catal...ages/an111.php for an-111 cable bushings.
Hal

[Hank Jarrett]

Re: Cable thimble bushing

Check to be sure the new cable end will fit through the guide tube in the fuselage before you lock everything down! I had to redo some because the cable end wouldn't fit. Next recover I am putting larger tubes in the fuselage to fit the later cable ends.
Hank

This time I swagged the ends with the wings on. Going to be a mess if I have to take the wings off. I will probably cut the tubes and open them rather than ruin the cables.

[Robert Lees]

Re: Cable thimble bushing

The tubular phenolic guides in the fuselage are removable for this purpose.

Inside the wing, the aileron cables fit through slotted phenolic guides (with the slots angled so that the cable won't slip out...I may have a photo).

Rob

Edit: found a photo...not too clear but it shows the principle, and yes, I had removed the cable from the guide myself!

Also, where the aileron cable goes through the last full-length rib, at the aileron bay, there is an oval slot in the guide (see second photo).

[TimHicks]

Re: Cable thimble bushing

I'll do Hank's check. When I dissembled the airplane, I had no problem fishing the aileron cables through their path. I didn't have to remove the fairleads in the fuselage guides.

But what I'm really looking for is the little plastic bushings that go on the inside of the thimble and have a hole in them for the bolt.
Do your planes not have these bushings?

Hal suggested that it is AN111. Steel. See pic below. But I'm pretty sure AN111 is not meant to be put inside of a thimble. I believe that it is meant to be used instead of a thimble. I don't want to do that. I want to find the little plastic bushing.

[Ray36048]

Re: Cable thimble bushing

I think this tread got off topic. The units from Spruce are metal. The ones from Taylorcraft were phenolic. I carefully removed the old one to reuse. I would think a piece of phenolic would work. If the metal ones from Spruce are OK for size, I would think they are OK too. These are used with out the thimble.

[TimHicks]

Re: Cable thimble bushing

I guess I'll clean and reuse my old ones. I hope that I still have them all.
Mine don't appear to be phenolic either. You can see in my first picture that the bushing is deformed a bit.
Seems more like a thermoplastic (like Nylon or PP) than it does phenolic.

[paulnuss]

Re: Cable thimble bushing

IF the intended use is to put a smaller-diameter bolt through the cable end, then indeed the AN -111 cable bushngs are what are intended for that purpose, at least nowadays. I wouldn't want a soft, malleable, or deformable plastic insert doing that job.

[Robert Lees]

Re: Cable thimble bushing

My original cable end bushes were also metal...the cables were spliced, not nicropressed.

[Hank Jarrett]

Re: Cable thimble bushing

Rob, the new thimbles and cable bushings wouldn't fit through the tubes with the phenolic guides removed (yea, I did think to do that) ;-)
The tube alone is too small for the thimble with a cable bushing. What was in my plane before was the thimble alone and someone had squeezed it so it would fit through the tube, NOT a proper practice! If the cable was placed around the cable bushing alone (yes, it IS supposed to be the steel one, NOT the plastic) it probably would have fit, but according to the manuals you are supposed to use a thimble and a bushing with that size bolt. I have seen a lot of cables simply wrapped around the bolt, but I can't imagine ANY mechanic approving of that. It isn't the size of the nicropress that won't fit, it is the diameter of the thimble.
I just got tiered of messing with it and put the cable through the hole, then put the hardware on inside the fuselage, thus, can't get the wings off without cutting something. I choose the tube and then I will just weld in a larger diameter one so it isn't a problem the next time. I can turn a custom phenolic guide.
Hank

[TimHicks]

Re: Cable thimble bushing

The inside diameter of my aileron cable guide tubes (with the plastic fairleads removed) measures about 0.810" average.

The Nicopressed cable end (with a thimble and a plastic bushing) measures between 0.655" and 0.675".

So the terminations should easily fit through the tubes.

It sounds like what Hank is saying is that if you put the steel AN111 bushing inside of the AN100 thimble, it makes the termination too big to fit through the guide tubes. So I'm not going to do that. Correct me if I'm wrong.

So I still don't know what to do except either reuse the plastic bushings or make new bushings out of plastic phenolic or steel.

[Hank Jarrett]

Re: Cable thimble bushing

Tim,
The picture of your fuselage guides looks MUCH bigger than the ones on my plane. I wonder of they just used a bushing and weave cable before the war and could get away with a smaller tube. Either way, I will be replacing the tubes whenever I do a recover.
Hank

By the way, I do have a bushing (steel) in each thimble.

[TimHicks]

Re: Cable thimble bushing

OK, in that case, I'm going to order some AN111 bushings and assemble a cable end with AN111 bushing inside of the AN100 thimble and see if it fits through my cable guides.
I'll report back to this forum once I've done that test.

[Hank Jarrett]

Re: Cable thimble bushing

I need to MEASURE the diameter of my guide tubes next time I am out.
Hank

[3Dreaming]

Re: Cable thimble bushing

The AN111 bushing does not go with the AN100 thimble. They are 2 different ways of ending a cable. The bushings worked fine for places like the aileron bellcrank when the cables were made with a 5 tuck splice. When the cables were switched over to splices made with a nicopress sleeve there was a problem with the sleeve interfering with the bellcrank. The older 5 tuck splice has a lower profile that the newer Nicopress sleeve splice. Because of this they started using the AN100 thimble to provide more clearance. The thimble is not designed to go around a small AN3 bolt, so a bushing of some kind is needed to more closely match the inner radius of the thimble. Unless Taylorcraft had a part number for the bushing I think you are on your own to find something. Like someone said before a metal or phenolic bushing should work OK. At least this is my take on it. Tom