Well I started my re-tabbing project this morning and all went well. I grinder the crap out of the area and cleaned it over and over with a vacuum and acetone.

I have layed a layer of glass 18oz (12 oz bi ax w/ 6 oz mat) and it is curing over night. I want to put a second layer on for added strenght. How do I prep the surface to lay new glass over the cured glass?

I am going over lap the cured piece by about 1/2 inch

same as before, grind and clean

later

Yep,but i would go atleast 1 inch over.

Thanks. How much grinding do I need to do. I am thinking just enough to give the surface some grit to make a strong adhesion.

Take some 60 grid and do it by hand ,just scuff it up a little,,,,,dont realy grind !
If it just sits overnight ,most likely u dont have to do anything just wipe down with aceton but not wet wet only a quick wipe for the dust.
The new resin will soften the old one since not fully cured.

What kind of resin are you using?

I am usuing a polyester based resin from US Composites. Imixed it pretty mild with the MEKP.

Any thing special I need to do?

I think the best was is to layup the next layer before the previous layer has fully kicked this way you get a chemicle bond and don't need to grind between layers.

you shouldn't need to grind it completely, just enough to knock off and burrs or ridges. If you used a standard laminating resin from USCompsites and no wax or finish type was used you should be ok.

best is to do as oldschool said, layup all at once if you can.