BC12d being rebuilt in Souht Africa

[TimHicks]

Re: BC12d being rebuilt in Souht Africa

My 1946 BC12D doesn't have that extra tube near the trim pulley that yours has.

[Theuns]

Re: BC12d being rebuilt in Souht Africa

Wow! that is a sharp bend, thanx for the swift reply Tim :-D
I see the lack of the extra weird little tube in the tail post area on yours Tim, I think it will be safe to remove it.....just find it so strange that it was in there in the first place.
At least that sorts out two of my questions.

I must admit that I find it "difficult" to rebuild this BC12d, as there are some "odd" ways of doing things especially wrt the trim and control cables that go slack as the colomb is moved!
I have never found this on Piper or Aeronca that I usually work on, but if it was designed like that and worked well since the '40's who am I to question it ......I will just have to do a bit of a mindswitch to get use to it LOL

Theuns

[Theuns]

Re: BC12d being rebuilt in Souht Africa

BTW, I see a RC model in the background there. Is that where you also started?

I guess once aviation gets under the skin you can not escape it!
Theuns

[Hank Jarrett]

Re: BC12d being rebuilt in Souht Africa

Mine looks like that too. Remember that the trim cable does not move very much or very often. It would take MANY decades to wear through. Of course many of our planes ARE many decades old so we need to look at it at least on every recover!

Hank

[Hank Jarrett]

Re: BC12d being rebuilt in Souht Africa

I would NOT remove the "T" cable support guide! You are DE-configuring the airplane by modifying the control system. NOT a good idea! DON'T DO IT!

Hank

Not sure why it is gone on yours Tim. It is on the fuselage drawings.

[TimHicks]

Re: BC12d being rebuilt in Souht Africa

Hi Theuns,
Yes I do come from a RC flying background.
But I built the TaylorCraft model that you see in the background as a "display only" model to use to test the paint scheme for my full-scale TCraft.

I'm glad that I did. Because I learned several things that I have used in the painting of the full-scale one.
Tim

[Theuns]

Re: BC12d being rebuilt in Souht Africa

Hi Hank, are you refering to the T-bar in my most left hand pic? The "standoff" that pushes the trim cable down?
I defenately am not planing to remove that ! I was asking more about the short tube fouling up against the trim pulley :-)

Thanx

Theuns

[Bigdog]

Re: BC12d being rebuilt in Souht Africa

I attach a few pix showing the cable routing and there are a few places where the cable goes through the "standoffs" and change direction rather steeply, is this normal for Taylorcraft??

There is also an alluminuim "cable guide block" that keeps the trim cable to the rear elevator pullye, but you can see how it does not line up well with the elevator in neutral position, it this "taylorcraft" or maybe an attempt by the previous owner?

The trim cable standoffs and guides, at least on my L-2, have brass-looking inserts. I assume a piece of brass tubing was pressed in. They don't look like a machined bushing. I believe my cable guide block is phenolic rather than aluminum. That would ease the wear issue.

[Theuns]

Re: BC12d being rebuilt in Souht Africa

Hi Greg, you are absolutely correct, I did see the brass linings today.
The block at the back is however alluminium on the one I am working on. Maybe a less harsh nylon block would be better??
To get fenollick here is darn near imposable!

Theuns

[Hank Jarrett]

Re: BC12d being rebuilt in Souht Africa

That is the one I was talking about (the up side down "T") I haven't seen that other tube by the pulley before. What year is your fuselage (SN or door type)? Anyone else have that tube on the tail post? It isn't on my 41 or 45.


Hank

Hi Hank, are you refering to the T-bar in my most left hand pic? The "standoff" that pushes the trim cable down?
I defenately am not planing to remove that ! I was asking more about the short tube fouling up against the trim pulley :-)

Thanx

Theuns

[Hank Jarrett]

Re: BC12d being rebuilt in Souht Africa

My blocks are Phenolic with brass or copper inserts too. They look like they have been flared out to guide the cable and had some grooves worn in the metal but none had gone through to the block. The worn ones were symmetric so I flipped them over and they are wearing on the other side of the hole now. Should be good for the next 75 years, then I will worry about making new ones. ;-)

Hank

I am an optimist.

[Robert Lees]

Re: BC12d being rebuilt in Souht Africa

Theuns:

The original block was a compressed fabric phenolic compound, 1/4" thick, 1/2" wide by 2 1/2" long, with copper inserts to provide sacrificial wear in favour of the trim cable. The reason for this was that the block could be replaced through access panels, whereas replacing the trim cable could realistically only be done at fuselage cover time.


The photo in the attachment (at the foot of this post) shows the original phenolic block for a 1946 BC12D. Note that the central bolt-hole is slotted, to as to enable vertical adjustments upon assembly.

You can see that mine broke, so what I personally did was to make a new block out of solid copper:


Above: dummy pulley rig for cable alignment. Pulley = 2" diameter

I don't think aluminium is a good substitute. Get a piece of copper busbar from your local avionics supplier or building supplier (that's what I did).

From the above photo, you can also see that like in TimHick's picture, there is no tube that your photo shows...I wonder if this was an attempt to emulate Austers with an up-stop? For sure I think I've seen something similar.

[Robert Lees]

Re: BC12d being rebuilt in Souht Africa

To get fenollick here is darn near imposable!

Theuns

Phenolic. It is used in HVAC (High Voltage AC) installations the world-over as an electrical insulator for circuit boards.

[Theuns]

Re: BC12d being rebuilt in Souht Africa

OK, I have an idea of how to fix this problem now after your inputs :-)
I think the solid copper block will be "workable" for me. It is easy to find and make.
Hank I am not sure about the year model of this section of the fuselage, I will have to make sure, but clearly that little tube should not be there.

Theuns

[Hank Jarrett]

Re: BC12d being rebuilt in Souht Africa

We may be able to estimate the age of the fuselage with the serial number off of it. Don't worry if your Fuselage SN does not match the airplane SN. The fuselage number was often different if they moved a plane on the production line before the planes number was entered and LOTS of planes had fuselage tube structures swapped out.

Hank