Line thickness vs brass micro tube thickness.

[ETG]

Dear group,

Here is my first question on this forum.
I am gathering materials to use on a 1:32 Sopwith Camel. I received three lengths of brass micro tube 0.5 x 0.3 id x 30 cm.
A testbuild worked out fine, although my age (46) and eyes (they used to be better, twenty years ago) were working against me.
Geez.....this stuff is SMALL!
Looking around for more info and materials I think I found a problem I may encounter during the build. Monofilament line comes in all
sort of diameters. Micro tube does not !
Drilling it out is an option, but it allows only one or two more thicknesses of filament to fit. However, the next thickness tube is 1 mm. That's a 100%
increment, instead of the 10, 20 or 30% I need, to stay close to the correct scale.

One way of avoiding the problem of having to find all sort of diameters of tube and line, is to choose one diameter of line (0.14mm ?)and one
diameter of tube, 0.5 x 0.3.
Non-insulated cord end terminals come in a large variety of diameters, however, even the smallest one may be too big, even for 1:28 scale,
so this option is out. They do have one BIG advantage: hard copper tube with a layer of tin, thin wall and a huge variety of diameters.
Many terminals per package, for just pocketmoney. Minimal length is about 4 mm, max is about 16 mm. (numbers differ for larger diameters.)

On real airplanes, there may be rigging wires and turnbuckles of different diameters and sizes, but the best option I can think of is to limit
them to just one or two sizes, on a model.

Please give some advise, let me know how you guys deal with this issue.

Cheers,

Erik.

[gcn]

2lb fishing line comes in a thickness that allows you to thread through  a 0.3mm id tube twice, so that's all fine and dandy. You will however need something similar to an Optivisor to see what the hell you are doing, without one you're into a whole world of pain.

That's what I use, and it looks ok to me. I don't bother drilling out tube that's in the too difficult tray.

[Chris Johnson]

I can only speak for myself but I limit my brass tubing to the 0.5 mm x 0.3 mm interior stock, together with Maxima Chameleon 2 lb fishing line as it seems to be very consistent in diameter. However, I'm finding that this line is discontinued in the 2lb strength at my usual haunts. Magnifiers are a must for me when threading the second strand of mono through the tubing and even then, I have to resort to poking, prodding and spinning it to get it through on some occasions. Whatever materials end up working best for you, I can't stress enough how important it is to give yourself lots of slack in your line. This enables you to do the threading well away from the model, which makes it so much easier.

Cheers,

Chris

[Edo]

Hi Erick!
I can only echo what has already been said, I usually use 2 brass diameters 0,5 and 0,4 mm with 0,12 and 0,1 mm mono respectively. I found that pre painting the mono, even if it gives a better look, makes it just a bit thicker and/or roughter so that it slips with more difficulty into the tube: so don't do that.
Also it is very easy to crush the tube when you cut it, to avoid this I roll the tube under a blade to cut it, then I sand the opening and also open them a bit with a pin, I tried to drill through the tube, but I ended up breacking the drill... So I won't do that again 
Hope this helps,
Ciao
Edo

[kornbeef]

Erik, hi and welcome.

I use invisible mending thread though I'm going to try other mediums. 

Just as an extra tip I tend to cut mybrass  tube using an old 0.3 drill  slipped inside it for 0.5 tube. It helps stop the tube burring over. for smaller bore tube I have some stainless spring wire that I use for the same reason.

For fitting eyelets to turnbuckles I drill out 0.5 tube to 0.35 but just the end. If you have a 0.3 drill just run it through the sections of tube to clear any swarf or dirt out before threading.

Keith

[Des]

I will echo what everyone else has said. I use 0.5mm Griffon Model brass tube, it is very consistent in size both inside and outside diameters. The fishing line I use is like what Chris said, Maxima Chameleon 0.12mm, this will easily fit inside the 0.5mm brass tube twice and a small drop of CA holds it extremely well. The main thing to be sure of is that before you thread the line into the brass tube the line must have a very clean cut preferably at a 45º angle, this is very easily achieved by using a sharp scalpel blade.

Des.

[ETG]

Thank you all for the help.
The original problem still exists: on real aircraft rigging lines can have different diameters. And turnbuckles come in different sizes.
Is this something that you guys take into account or do you rig your models with one and the same thickness line and one size turnbuckles?
Because of the small size, this is something I can not see in the pictures of your models.

Personally, applying the "One size fits all" principle on my first model, using those tiny parts for the first time, would be great victory
for me, anyway !  ;-)
I have used thin cotton thread (black, round and smooth) and EZ-Line on my models, with acceptable results, but those models are,
ofcourse, nowhere near competition or museum quality standards.

_______
Erik.

[kornbeef]

Erik,

I tend to use 0.5 for most turnbuckles but for control cables I sometimes step down to 0.4 or even 0.3 if its a simple non looping run. By which I mean not coming back on itself, I often finish contol horns, pedal assemblies this way.