My goal is to make some single layer flat sheets that are UV protected.

My thought is to use a Polypropylene Sheet, use a roller to lay on a layer of GC50 Gelcoat, let that set for the 2-3 hours, lay down a dry sheet of CF cloth, then wet that in with the epoxy resin, place another Polyproylene Sheet on top and them clamp them together.

Is that the right approach?  Will the GC50 be enough UV protection or would it stil need a spray on UV Laquer wet sand/polish on top?  I'm trying to avoid that extra labor.

 

Thanks,

Eric

Hmmmm... Single layer probably will not be very good... you'll be able to see through ... and have very little strenght ...

Here's how I do flat sheets..

I use an old bathroom mirror, bonded to a 25 mm thick hard plywood plate.  (This way the flat sheets come out flat, and with a "mirror-finish")

I use Easy lease on the mirror and polish it up between each use. (first I tried other release agents, they worked, but EasyLease is the king!)

I spray on GC50 using an old spray-gun I have modified to have a large aperture (around 4 mm)

I let the GC harden for 3 -4 hours and then i wet-lay my choice of carbon fibre on to the GC50 using a bristle roller (not too hard on the roller)

I finish the "pack"  (can be multiple CF, kevlar/diolen and glass layers) with peelply, and perforated release film + a thin breather cloth

On top goes the vacuum-bag-film "gum-sealant" along the edges, and I "gum in" the vacuum hose. On top of it all goes another piece of the plywood (with a cutout for the vacuum hose.)

This setup works very well doing wet-lay --- Next week I'm going to try it with infusion.

If I want "mirror-finish" on both sides, I normally get it clear-coated directly on the surface that the peel-ply leaves with just a quick 400 grit sanding.. .works fine.. In fact it works so well that i have confused the two sides... I only spotted the very slight difference in direct sunlight....

"Sapere Aude"... Dare to KNOW!

The written word is the only truly efficient vehicle for transmitting a complex concept from mind to mind...

103% of all people do not understand statistics...

Do not adjust our mind, theres a fault in reality :-)

Similarly I have consistent success producing sheets on a sheet of glass (flat rear hatch screen).
I use easylease + wax for release and infuse the stack with peelply and normally infusion mesh over the top before the vac bag.
Works great and the glass surface clears up quickly for re-use.
Stuart

Glass is the best for flat sheet by far.  Brand new polyprop sheet is good for a few pulls then it quickly picks up scratches and looses its gloss.

Thorough usage of the bristle roller is key to a good bubble free finish for wet lay sheet.

You have to be careful not to pull the weave or you will notice slight wavyness on the finished sheet, so even strokes are best.

Wet lay is simple and quick for cosmetic grade sheets.

Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant

Thanks!  I'll give it a try.