Various sources, but my latest order was from CST.

www.cstsales.com

Can be a little on the expensive side for some items, but also have a great selection (have seen things there that I have never seen anywhere else), and great customer service. They also threw in a technical spec bulletin with my order (for pro-set). Great bit of info - do you have one? It shows all the strength, TG, etc specs for the epoxy, including the difference between post cured and non post cured (at various temperatures as well). Very useful info 🙂

Where do you get yours?

Well... I did only a little bit of this in the late 80's... and now it's time to really get into it. I'll epoxy my fins to the motor mount this week (on my future L3 bird), then I'll layup the fins with 8.9 oz FG cloth, make the fin slots bigger so it will fit in the tube... then lay 'em up to the tube with either 8.9 oz (again) or 3 oz. FG. I'm actually trying to keep the nose weight I'll have to add down, which is why I'm starting from the bottom, so I'll know the nose weight to add last. I've been staring at it for weeks, trying to get the courage to get into it. Not so worried about epoxying the FB cloth, as I am getting those fins straight! Only get one shot. 🙄 I've read a lot about composites. But the only way to do anything is to just do it. I "know" you make sure the X in the weave is on the joints, etc. Thank goodness the first attempt will be mostly hidden by the body tube. 🙂 I "know" to use those small paint rollers from Home Depot to apply the epoxy (using Aeropoxy, slightly stronger than West, so I'm told), and I've been saving those fake, plastic credit cards that come in the mail to wipe off the excess epoxy. Finally a use for 'em! So... any wise and experienced words before I start?

Doug, the Aeropoxy I got from Tim Thomas of GLR was a cloudy blue resin and a pretty deep red hardner... then became clear as it began to set. Is this similar to West? You mentioned that you were surprised it was clear. This might be what you meant. Everything seemed to go well. Fin jigs look straight, as does everything else. I asked my wife to not let me go into the garage to keep checking on it. It's done. Fins are mounted. Next comes the layup. 🙂 I'll never use another epoxy again. It is fantastic!

No, I haven't seen what you described. The West Systems is clear for both resin and hardner. I was sort of kidding about being surprised because all the stuff I had used was an amber color.

Doug

Hmmm... Aeropoxy turns clear. Surprised me. Good stuff.

Interesting...

I've never used aeropoxy, but the ones I've used are West (starts clear, ends clear) and Pro-set (starts amber [orange hardener, crystal clear resin] and goes clear as it cures).

Thats interesting the 205 fast hardener for west systems that ive used actually has a redish tinge and makes the expoxy red color when liquid but dries clear.

Interesting...

I use the 206 slow hardener with west, never tried anything else...

I use the 206 as well. for laminations stuff. BUT when doing work with things like G10 glass or filiment/convolute wound glass tubing the speed of the epoxy is irrelavant as it is only a surface bonder not a penatrant like when using Phenolic or cardboard. So I have less down time when using the Faster 205 hardener.

What kind of working times do you get with the 205?

I may look into that, as that is currently my biggest problem with west (when I use it for bonding).

Conway, the Aeropoxy is similar... mixed blue and red, got a brownish color, then it set and dried clear. Kinda cool.

here is some differences. Note the minimum temps they are testing with. Increased temps decrease cure times. Ive seen the Fast cure in a couple hours to overnight.

205 Fast Hardener

205 Fast Hardener is a medium-viscosity epoxy curing agent. It is used in a majority of situations, at lower temperatures and to produce a rapid cure that develops its physical properties quickly at room temperature. When mixed with the 105 Resin in a five-part resin to one-part hardener ratio, the cured resin/hardener mixture yields a rigid, high-strength, moisture-resistant solid with excellent bonding and coating properties. Not intended for clear coating.
Mix Ratio, Resin:Hardener
Pot life at 72°F (22°C)
Cure to a solid state
Cure to maximum strength
Minimum recommended temperature
Pumps required 5:1 by weight or volume*
9 to 12 minutes
6 to 8 hours
1 to 4 days
40°F (4°C)
300, 306-25 or 309

206 Slow Hardener

206 Slow Hardener is a low-viscosity epoxy curing agent for use when extended working and cure time is needed or to provide adequate working time at higher temperatures. When combined with 105 Resin in a five-part resin to one-part hardener ratio, the cured resin/hardener mixture yields a rigid, high-strength, moisture-resistant solid with excellent bonding and coating properties. Not intended for clear coating.
Mix Ratio, Resin:Hardener
Pot life at 72°F (22°C)
Cure to a solid state
Cure to maximum strength
Minimum recommended temperature
Pumps required 5:1 by weight or volume*
20 to 25 minutes
9 to 12 hours
1 to 4 days
60°F (16°C)
300, 306-25 or 309

Other epoxies are intended to be heat cured. I believe Aeropoxy is one.

Aeropoxy for laminating (layup work) can be cured "well over 200 degrees [F]." The working time is an hour. I'm sure Warren is right about another higher temperature epoxy from Aeropoxy, just haven't come across it yet. I finished filleting around my fins on the motor mount, and I've decided that instead of laying up the whole fins at this point, I'm just going to layup FB rectangles to secure the joint to the motor mount and come out just past where the body tube slips over the fins. While I want strength, I'm really concerned about the weight of my aft end. The 3 fins themselves already weigh ~4-5 pounds. I'll do a full covering after I epoxy the fins and motor mount to the body tube.

Well, layed up the fins to the motor mount. Didn't even have to use those fake credit cards from the mail! That miniature paint roller smoothed everything out. I'll admit I never really like this part. But this was too easy. It wetted out perfectly. I was able to do all three fins at one setting. No runs, no drips, no errors. Aeropoxy doesn't have a pump system... so I'll have to wait and see if I mixed it right. 😯 🙂

Glad you like the paint roller tip Bruce!! sounds like it made it a snap for you.