Working with fiberglass

[trikypaint]

After laying down your fiberglass and letting it cure, you'll notice a sticky residue that will remain on top that will gum your sandpaper every time. I find it best to wipe the fiberglass first with thinner prior to sanding to keep the sandpaper from gumming up.

Thought I'd share.

 

[rex]

I've heard that quite a bit and guess it works well.I've always knocked the top off with a 36 grit disc on the grinder and then went to 36 on the mudhog.Any pockets get dug out with a knife and 80 grit or lows hit with the grinder for another coat of glass or the smooth out with filler.

 

[hrlymnsss]

say guys try this trick for glass work i found this works good on all the vett panels ive done and repairs lay some wax paper over the top and take a spreader this way you can work all the bubbels out and it keeps the resin in place and for some reason ive found doing this usually leaves it scum free i think it keeps all the hardner on the repair and doesnt eveporate before it kicks

 

[Bigdan1928]

It sound like your not using enough hardner.Ive bennbulding glass hoods for semis for 5 years and have never heard of this. When i do repairs we use cheapo evercoat resin and it hardens out in 25-30 mins.Be careful of the hardner in the little plastic tubes, it tends to be weaker than the quality hardner you can buy in a pint size.If you use the little hardner tubes, add 4 or 5 drops more to each 2-3 oz.Remember, if the top isint dry,then the rest wont cure all the way,and that leaves weak glass. And if you add too much hardner,it will dry to quick causing millions of hairline cracks that you cant see leaving it weaker than uncured resin.

 

[MPAVLAS]

WHEN YOU USE REGUALR FIBERGLASS RESIN IT DOESNT CONTAIN ANY WAX WHICK IS NEEDED TO SEAL THE FIBERGLASS SO IT DRIES COMPLETELY THE CHEAP AUTOMOTIVE RESINS ALREADY CONTAIN THIS WAX, IF YOU DONT WANT THE CHEAP STUFF JUST BUY SOM STYRENE WAX YOU CAN GET SOME WWW>FIBERGLASSSUPPLY.COM

 

[Straykat]

You can add wax to the glass ...or you can spray a surfacing agent over the glass while it cures.But for small jobs the best approach is to just wipe the surface down with acetone after it cures..

 

[DaveA]

[ QUOTE ]
After laying down your fiberglass and letting it cure, you'll notice a sticky residue that will remain on top that will gum your sandpaper every time. I find it best to wipe the fiberglass first with thinner prior to sanding to keep the sandpaper from gumming up.

Thought I'd share.

[/ QUOTE ]

I saw this post, and even tho it's older, I thought I'd add my .02...

Make sure the polyester resin you finish with is just that, a Finishing Resin. If you still have a tacky surface once the resin is apparently cured (given enuf time) it's possible you've used Laminating Resin, which stays tacky to accept the next layer of resin & 'glass cloth. As stated above, you can clean it with acetone perhaps, or lay a coat of finishing resin over it.

Hope this helps. however belatedly.

DaveA