I have a mould of a car bucket seat id like to use, just wondering howamy layers of 200g black diolen twill would be needed and any core material? Ie coremat? 

Anyone?

Hi, not sure on the exact properties but pretty much anything is going to have higher properties than CSM glass.

Cores are fine but I wouldn't use them all over, just up the back. Wherever you have a mounting point I'd put a few extra layers and no core so the laminate won't crush when you bolt through and it will give a more uniform bearing surface for the bolt.

My old sparco glass seats are about 4mm thk CSM if that helps and thicken up wherever there's a mounting point.

You will have to do a test to be honest. You might find diolen flexible and either need a couple of layers of carbon or glass to add some stiffness... If you use a peel ply you can add more layers if you need to so I would start at 3mm thick and 9 layers. 

Forgot to add earler, there's a book here: http://www.amazon.co.uk/Composite-Matrials-Fabrication-Garage/dp/1929133936/ref=pd_sim_b_1?ie=UTF8&refRID=0TBECMTZFPERR5VWZ66J that shows how to do a CF seat but could be adapted for Diolen with a few extra layers