by Thomas Shinneman
I'll offer you some alternate methods that may save you time and frustration. The .6 or 5/8 oz. glass that was suggested in IMHO is the ticket. But this is some very fine woven material and lends itself to snags and runs if not handled judiciously. I would think that for some one just getting involved in glassing a .75 or 3/4 oz glass would be more user friendly. I know, what about the weight factor? In a second I'll tell ya how to work around it. I am assuming that you've not had any experience with glassing or its components.
We've covered the glass cloth selection already, now the resin or bonding agent. You can use any of the following for a bonding agent.
(the stuff they use on boats, etc)
extremely pungent vapors, requires thinner or such to clean up. But very durable also not compatible with some Epoxy resins.
Epoxy resin/Finishing Resin
Hazardous vapors, can be cleaned up or cut with Isopropyl alcohol, durable, easy to obtain, and sands fairly well.
Thin and Med CA.
Pricey, can knock your sinuses for a loop, possible allergic reactions, hard to sand but bulletproof.
Water Based Polyurethane or WBP
Easy to clean up, soap and water, easy to apply, very little if any noxious fumes, readily attainable, (hardware or lumber stores), and sands very easy. This is what I suggest to the budding Glassmiester.
As stated previously cut your glass 1-2 inches larger than the section you want to cover. Now, with some 3M 77 adhesive Lightly mist the the cloth. You should not be able to see any trace of the adhesive on the cloth. Very, very loosely roll the cloth from the bottom to the top. Gently lay the cloth on top of the area to be glassed and with a super soft 2-3" paint brush, gently brush the cloth flat onto the surface working from the center out each side. If you encounter wrinkles simply re-lift the cloth and work it again. This is why it is so important to only leave a trace of adhesive on the cloth.
Now that your cloth is in place, you can bond it to the surface with the WBP. Using a separate soft brush apply the WBP to the cloth from the center out and only heavy enough to saturate the cloth. The cloth will appear almost transparent when saturated. Use only enough WBP to saturate the cloth leaving it not only transparent but with a satin sheen to it. If its glossy or wet looking you have to much WBP. Grab a roll of toilet paper and gently roll the paper onto the heavy area to absorb the excess WBP. After you have applied the WBP to the entire section dust it with either Talcum Powder of Micro-Balloons. This will fill the weave of the cloth and hopefully alleviate the need of a second coat of WBP. When dry repeat the above overlapping the cloth slightly on the previously glassed section.
When complete sand down your overlapped areas with 220 and then the whole ship with 400. If you discover any areas that the weave needs filling, just go back over it with the WBP and Talc/Micro Balloons and refinish that area. The most important thing to remember is; it is the "Cloth" that provides the "Strength" not the bonding agent!! Any more than the cloth can absorb is just added weight and Sanding!!
Any questions or comments about this? - Tom Shinneman firstname.lastname@example.org