Fibreglass Techniques?

[Robert in Cumbria]

I need to learn a bit about fibreglassing techniques in relation to the Marlin bodywork.

I am well used to making fibreglass roofs which as a builder I have done quite a few, but the techniques seem different with the Marlin bodywork, are there any websites that you can recommend please?

I have looked at http://www.fibreglass.com/HOWTO/How-To.htm

Particularly I have cut an aperture for a boot lid in the back tub, I need to add a rim with a gutter to stop water dripping through into the boot and to give the lid something to close against. Probably need to reinforce the area where the hinges and catch will be too.

Mainly I need to know how to get fresh fibreglass to stick well to the underside of the tub. Do I grind it flat, or clean it in some way leaving the present roughness 'as is'?

I have resin, a big roll of random lay fabric, hardener and various pre-formed sections and flat lengths which are used for roofing.

In the short term I was thinking of bonding some narrow strips of f/g to the underside of the tub around the edges of the aperture just so I can place the lid on and secure with 4 Deutz fasteners for now. I can add the gutters later.

Is anyone aware of specific threads on this forum about fibreglass modifications please?

[Robert in Cumbria]

Re: Fibreglass Techniques?

Well, I am learning, mainly by error!

It would seem fibreglassing and cold weather don't go well together. The resin doesn't set, at least it hasn't yet, except the bits I warmed with an electric hot air gun. The rest is still a sticky mess. Will wipe it off with a thinners soaked rag tomorrow.

[listerjp2]

Re: Fibreglass Techniques?

Hi Robert

Sorry for not getting back to you before now.

To make the ridge I would suggest using foam underneath just using evostic to support it.

Then using the matting laid on top apply the resin, in cold weather use more hardener than recommended.

Make sure you soak the matt completley, it should go clear.

Normally use 10 grams Epoxy Resin to 5 Grams Epoxy hardener sometimes known as caterlyst.

At 60 F this should not go off for at least an hour.

The hardener will make the epoxy heat up anyway.

Make sure you use the stippled roller to sqeeze out the air otherwise it will rise in lamintes.

What ever you do dont use paste, this is for filling holes not making new parts.

Dont worry about doing it to big or thick you can cut it to size withing an hour.

Rub and cut down to correct thickness and size and hey presto there you are.

Opps forgot, dont forget to cut the foam off the back when finished.

Hope this helps?

Adrian

[neiltechspec]

Re: Fibreglass Techniques?

Try adding a lot more hardener, at least 4 times the amount. This should cause it to generate its own heat and go off quicker.

Could cause cracking though, so try a few test pieces 1st.

Neil.

[CosworthCabrioLee]

Re: Fibreglass Techniques?

Hi Robert you can get a book at the library called how to repair fibre glass by miles Wilkins
A fantastic book and it helped greatly when restoring our lotus élan