Thick Glass Fiber Laminate

What about making a sandwich?

It is a very good idea, and I have done it before with Carbon and Nomex honeycomb, but now I need to make those discs in full glass fiber + Vinilester resins.

If the experienced guys say it needs to be done in thin layers...

Would you believe a talking cat if he said just go for it in one thick layer and be damned?

If you ask enough people you'll eventually get the answer you want... it doesn't mean it will be right though.

Experiment, that's the best I can suggest.

Del

Look up exothermic reaction.

Chemical crosslinking of vinyl ester resins generates lots of heat.

You might be able to do this by inhibiting the cure speed. Maybe cooling the mold would work, or using less catalyst.

Depends on the physical properties you need.

And why not an epoxy resin?

Epoxy resin is not allowed as customer requested that product with chemical resistance to sulphuric acid, where vinylester is second to none.

Have not had good results trying to cool the mold. That was with epoxy, but even so.

Take a look at the Wind Blade Manufacturer they do it in one step (using Resin Infusion) and have a compareable thickness if not thicker to your project. But do it in better quality because the wind blade´s lay-up is sometimes horrible.

Try it!

Good Luck

Woven fiber glass cloth when compressed in multi-layers is much denser than fiber mat, therefore it uses less resin, and less resin equates to less heat.

Stamp out 50-60 discs of fine weave fiber cloth.

Weigh the empty mould (and compression clamps).

Lay into the mould so that each layer is rotated 45° from the one below until the thickness is 1.5" when compressed to say 500Kgs.

Weigh the mould again, then using the density for solid glass work out the volume of air gaps in the weave. This gives you and exact volume for the amount of resin required.

Pour in the resin, compress to 500Kg/1.5" forcing the resin into the cloth weave and between the layers

Leave to cure.

Tolerances can be very finely controlled using this type of pressure moulding.

Use the resin transfer method and do not scrimp on the fibers, the resin is only the bond and has little strength. With a small vacuum pump you can draw the resin in avoid any air pockets minimize the amount of resin and I suggest minimum activator as recommended by manufacturer. Kick off time can be controlled somewhat by temperature of mold and air in process area. Slow activation will dramatically reduce heat from activation and provide stronger part.

I have circumstances where there has been a lot of resin left over in my ice cream container/bucket and yes there is heat but not enough to cause a fire.

Jim