Smooth Application of Epoxy

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Smooth Application of Epoxy

Postby bluemax » Thu Dec 06, 2012 9:30 am

This question may have already been asked and answered, so forgive me in advance. Again, I have not yet started on my kit, but as I was moving parts around in my building yesterday, I took notice of the factory-applied epoxy on all the various parts. It's the gray stuff. . . . Hysol, I think? I've got a couple cans that were included with my kit. Actually, I've got two cans of each, resin and hardener, since I ordered the aluminum leading edge for the wing.

The epoxy application is. . . to say the least. . . PERFECT. It looks like it was done by a robot. Very smooth. . . no strands poking out of the bead. Are they using some type of an application tool. . . like a cake decorator's icing bag? It doesn't appear to have been smoothed by a finger, or a tongue depressor. It would be nice to duplicate the factory's results, once I start doing my own.

Max Rentz
Newark, Ohio

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Re: Smooth Application of Epoxy

Postby SheepdogRD » Fri Dec 07, 2012 12:20 am

At the factory, they use a commercial dispensing gun. For the mostly smaller jobs we do, we can get away with simpler (and less expensive) techniques.

I cut a couple of component dispensing blades out of aluminum scrap -- about 1" x 3". They make it easy to get the epoxy components from the cans onto the mixing board, and they don't need to be cleaned up or wiped off -- I leave them right in the cans.

I wear disposable nitrile gloves (the blue ones from Harbor Freight) all the time I work with epoxy. I keep paper towels handy.

I mix on a piece of .060" aluminum covered with parchment paper (parchment is cheap and disposable). When mixed, I put the epoxy into a heavy ziploc baggie, down in one corner, and twist the baggie to make the "icing bag" you mentioned. I nip off the corner and apply the epoxy. Once it's set up a bit, but when it's still pliable, I wet a (gloved) finger with alcohol, make sure I have nice fillets with smooth surfaces, and clean up any "oops" areas and sloppiness. I don't spare the alcohol -- it works great.

It's surprising how close you can get to factory appearance this way.

If I was just starting, I'd find a few non-Highlander things that need epoxying, and give the system a try. It doesn't take long to be proficient.
Richard Holtz
Highlander N570L -- Ms. Tonka -- in gestation

If just enough is really good, then too much ought to be perfect.
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Re: Smooth Application of Epoxy

Postby jjacky » Fri Dec 07, 2012 7:17 pm

Dang dog I wish you had posted that years ago...great info
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