Easy way to make flexible hoses/ducting

[Matt Bacon]

In all kinds of places under the bonnet of your race or exotic sports car, and many classics, you'll find flexible hoses, like these directing cooling air to the brakes of an Aston Martin DP214:

I needed a large (4" or so in diameter) for an air duct on my 250 California. After looking for something to use for ages, it suddenly occurred to me that it might be easier to make one. And it is:

Ge a piece of sprue the right diameter for your duct, some gardening wire (available in many thicknesses) and some slightly porous, paper-like (not plastic) medical sticky tape from the chemists.

1) Wrap wire around sprue, and distribute as bunched or spread as you like.

2) On the sprue, wrap over wire with sticky tape in as few layers as possible (mine was wide enough to do the whole length with one piece, so there is only one seam, on the bottom)

3) Spray with Tamiya Rubber Black

Drybrush with appropriate metallic colour if needed, depending on whether the "coils" on your tube are visible or not. (probably best to leave it on the sprue for this, too)

A couple of short stubs cut from the sprue mandrel can be glued in place as mounting points.

Apologies if this is "old hat" but it seemed simple and easy to share!

bestest,

M.

Edited May 7, 2015 by Matt Bacon

[landman]

That might be a way to make make some nice heat riser ducts too when covered with foil.

[hedotwo]

Great tip!

Thanks

[chunkypeanutbutter]

Awesome!

[Quick GMC]

Instead of tape, use teflon tape. It's more flexible and you can extend or shrink it as you wish

[JohnU]

Can you paint Teflon tape? In other words will it stick?

[Roncla]

Can you paint Teflon tape? In other words will it stick?

I had issues with enamel paint not wanting to stick to teflon tape when making a duct like this.

I ended up painting a coat of thinned white glue over the duct and then painting it.

[curt raitz]

Try using "heat shrink tubing" too cover the wire wrap also...

and you can paint teflon with with any of Tamiya's lacquer spray paint and bottle paints.

[Bucky]

There is a matte black BMF on the market that might possibly work, although I don't know how it would do when the part gets bent into shape. I haven't tried it. It might be best to bend the part first, then apply the black BMF.

[BigTallDad]

On 5/7/2015 at 7:50 AM, Matt Bacon said:

 

 

Instead of a piece of sprue, consider using a threaded bolt. Wrap the wire around the bolt and the threads will result in consistent spacing of the wire.