[VAC] epoxy thinners- I don't think it's paint or lacquer thinner!

[JamesArakaki@xxxxxxx]

   I suggest a bit of caution here- I don't know if paint thinner or lacquer 
thinner will work right. Some materials will reduce the viscosity of epoxy, 
but may severely impact the properties of the cured material. Experiment with 
a small batch first to avoid having a major mess on your hands.
   I have successfully used a small amount of DENATURED ALCOHOL as an 
additive. This is sold as SHELLAC thinner, and might be the source of some 
confusion.
   West Systems is a line of epoxy products sold by boat supply stores. It is 
expensive stuff but works reasonably well. They offer a range of viscosities 
and cure times.  You can get the literature from a boat store. You are 
looking for a low viscosity (thin) resin/hardener combination for dryrot 
applications. 

   There is a large range of materials sold as epoxies. Some of this stuff is 
downright toxic, intended for aerospace applications and never makes it to 
the consumer shelves. However, it does show up in surplus stock.  Epoxy 
normally sold to consumers is reasonably safe.
   Epoxy is not UV stable, so if used outdoors it should be painted. 

notes on other resin/catalyst products:

 -It is possible to use polyesters for interior work, but the styrene monomer 
in it has a severe odor problem. It's the same smell you find in Bondo body 
filler (Bondo is bulk filled polyester resin). You will be smelling this 
stuff for a long time if you use it indoors. Polyesters are UV stable and can 
hold up in sunlight.
 -Additives such as Phenolic Microballoons, Glass Microballoons, milled 
fiberglass fiber,  Silica, etc can be used to thicken resins so that they 
don't sag on vertical surfaces,  and can thicken resin to peanut butter 
consistency. Don't breath this stuff.
- Ureathanes are fast curing and stable but use Isocyanates as part of the 
curing process. Home use expanding foams and so on are OK. Again be cautious 
of surplus "deals" because many industrial and military ureathanes are very 
strong but require the use of a fume hood or fresh air breathing systems 
because the hardeners are so toxic.
-you can develope a sensitivity to epoxy over time. I believe it's a reaction 
to the amines used in the hardener. 

USE RESPIRATORS, GLOVES AND COMMON SENSE! When cured these materials are 
pretty safe, but the uncured resins and catalysts can cause health problems. 
READ THE INSTRUCTIONS and if possible get a copy of the Materials Safety Data 
Sheet (ask for the MSDS and you'll sound like a pro!)

jimmy