glassfibre intercooling tubes
Turbo Mini Forums

Anyone tried this? I figure if reinforced rubber is sufficient, then glassfibre is more than adequate for blowing air through.

The glassfibre tubes would be very light, and you could easily make them perfectly streamlined with flowing curves to minimise restriction.

I was thinking along the lines of using epoxy resin and carbon fibre cloth, which would look nice and be as tough as old boots.

Andy

its a good idea. could have the pipes exactly as you wanted that way.. :)
make sure they're not rough on the inside, thouh

Getting a smooth finish on the inside is not a problem. You can use the 'lost foam' method of moulding.

This is perfect for one off castings, as the master is sacrificial.

You make the shape of whatever you wish to cast in glassfibre out of closed cell polystyrene- the pink or blue stuff they use for insulation.

This can be cut with a bandsaw (messy) or better, a hotwire.

Smooth the foam until you have the sculpted finish you require.

Then lay-up the resin and glass over the polystyrene.
When the resin has cured, dig out the bulk of the polystyrene, and melt any residue out with acetone (the resin won't be attacked).

Hey presto, finished hollow tube, with a nice smooth finish.

BTW, this method only works if you use epoxy resins. If you use polyester resin for this method, the resin melts the foam.
In this instance, you will need to give the foam a barrier coating of PVA glue.

Andy

you need to make up a batch then and start ebaying them.
i'd buy them, as it'd save me scrap-yard-hunting time.

What set-up are you building?

I'm using a T2 with Series 2 RS IC.

Was looking at 36-40mm pipe work to keep the lag down.

Been taking a peek today at the crock-o-shite Astra combi diesel van at work.

That looks like it has the right gauge of pipes for the rubber bits.

Might help if you're scrappy ratting.

we've got a T3 with 2wd cossie intercooler.

Uh huh, bit of a difference there then. lol

Well the technique to make these pipes ain't difficult. Infact I reckon if you really went for it, you could probably get the tubes made in a day.

Andy

I might have a go, and put up a tutorial.. can you PM me exactly what i need, as i've never done it before. cheers.

An alternative to the foam is to use wax. Carve it as you would the foam, the only difference is that you melt the wax in a cool oven and the inside surface finish is very good.

Where would you get that sort of wax Mirage?

http://mini.twisted-design.net/blog/

I like the sound of this!! we need more info, are there any good websites on this with lots of images of the process?

Team Racing

Would there be any way to colour the pipes? just to keep everything neat and tidy under bonnet :)

http://mini.twisted-design.net/blog/

Or you could find some where local which makes exhausts. They will bend some stanless stuff for you for not much money. Someone does the hard work for you and you can have a set of pipes ready in about 30 mins

Don't know about online sites showing any techniques.
I learnt this technique through my modelmaking activities- it's known as the lost foam process, and is ideal when you want to produce a one-off part. A dig around on google may unearth some links.
Here is one that shows some results with a small glider fuse-

http://www.favonius.com/soaring/lost_foam/lost_foam.htm

Wax is a decent if somewhat expensive alternative to foam. Good wax can be purchased from Alec Tirantis. I'm sure there are other suppliers, but that's the one I use.

Anyone interestd in learning fibreglass work should check out this book-

'The Glassfibre handbook' by R.H Warring

This will equip you with the knowledge you need to work successfully with this material.

Andy

Edited by Andymini on 8th Aug, 2005.

All this sounds very good - but consider the forces at work on a 2" diameter pipe with 20 psi going through it...
The tensile load on the pipe diameter is actually quite high

I'm not overly convinced that achieving a smooth internal surface is worth the effort either (don't confuse smooth and poor flowing) as an example - consider how 'smooth' the inside of a decent turbulatored intercooler core is(n't)...

Edited by turbodave16v on 8th Aug, 2005.

Dave I have considered the pressure on the pipes.

The tensile strength of a carbon fibre/epoxy resin laminate is very high. In a cylindrical form this will be very strong.

Getting a smooth finish inside isn't difficult at all, so you may as well reap a little benefit from it, however small.

The main reason I'm looking into the technique, is that it's easy to make a plug that will giving smooth flowing curves to the pipes.


The other alternative I've considered is beating out the pipes from sheet copper over a wooden mandrel.

The copper piping may benefit from a small intercooling effect too.

Andy

not sure how relevent this is but glassfibre does not dispell heat at all

Actually, I would guess that the lack of heat transfer would be beneficial to the air charge, because it would not pick up heat from under the engine bay (and the tubes generally run right over the engine and/or the exhaust!

Still not too sure about the burst pressure of a home-made CF or GRP tube, though...

**************************************
1967 Cooper 's' Turbo build @ www.drjing.com

wheres smudger when you need him, carbon fiber pipes showing weave would look mega cool.

no longer a series, but still 1.3 turbo.