My understanding is the thickened Thixo is more for gluing things together, filling gaps, and such. Plain old epoxy is best for wetting down fiberglass, building up thin layers of such for repairs. I’m still learning, but my thought is that unless you add fiberglass cloth or matting or a filler fiber like 404, epoxy alone would only be really for sealing, not repairing.I've been using the two interchangably in wood repairs. (Like repairing splits in wood rudders and daggerboards).
Now I'm thinking that's not such a good idea!
"Straight" epoxy?Epoxy is like rum, you can use it straight or add stuff to it to get the desired effect.
The epoxy resin base is the starting point, then you add your choice of hardeners to get it to heat up and cure from a liquid to a solid. Fast, medium, slow, ultra slow...the hotter your air temps are the slower we want it to cure.
To the resin/hardener we can decide if we need more of a harder, stronger structural adhesive or a softer fairing compound.
Where folks run into trouble is using epoxy or other adhesives on wood, especially raw wood like a split rudder. The wood grain needs to be sealed to the point where it stops soaking in adhesives. Straight epoxy is a good way, several coats until it is soaked in. Then do the final fastening with a thickened epoxy to fill in all of the tiny nooks and crannies in the joint. Even with THIXO thickened epoxy adhesive we know it will soak in a bit, sucking the adhesive into the grain and the joint. So we leave a little extra during application with that in mind.
Soaking in would NOT be a factor when sealing up a fiberglass joint, but straight epoxy running out of the joint could be, so that's why we use thickened epoxy. THIXO is the right consistency for that repair.
I had to ask, because it takes only a drop of hardener to turn the liquid epoxy into a solid. It does take time, but I'm in no rush.Fussy fussy fussy. I know you know darn well he meant epoxy and hardener ;-). And alas I seem to be unable to apply emojis, so take this as verbal confirmation that I’m poking at you in a good-natured fashion.
Yes yes 100% yes!PS:
"Amine blush, a byproduct of the epoxy curing process, may form under certain conditions. This waxy film is water-soluble, but many organic solvents are ineffective for removing it. That is why we suggest washing an epoxy surface with water (water clean enough to drink) using a Scotch-Brite™ pad (or wet sanding with waterproof wet/dry sandpaper) and drying it with paper towels before continuing with another operation. Soapy water, or water with ammonia or bleach, is not necessary and may leave its own residue, which is another possible surface contaminant."
Surface Preparation | WEST SYSTEM Epoxy