This afternoon I applied Cortec to my rudder ribs & spar... and it's a mess.

I used some denatured alcohol (as in HomebuiltHelp's "Metalworking 101" video) to thin the Cortec, and stirred the heck out of it. The can is about a year old. I applied it with a foam brush.

Now it looks (and feels) like I coated the parts with thick, stringy contact cement.

Am I doing this wrong? Has my Cortec passed its expiration date? Does anybody have recommendations for an alternative?

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Hi Patrick,

I think Cortec is a great product. I thin mine with lacquer thinner and keep a small quantity mixed up in a plastic container for daily use. The lacquer thinner helps it to dry quickly. I apply it with a sponge. I usually take a regular kitchen sponge and slice a 1 inch wide strip. I dip it in the cortec and slide it along the area to be protected. That is probably the same as you are doing with the sponge brush. I only protect the surfaces that mate against another surface.

You may be putting the Cortec on too thick. I have just a thin coating of the Cortec on the surfaces I am mating.

I hope this helps,

Tommy Walker in Alabama
I'll strip the parts--I imagine lacquer thinner will work for this too--and try thinning with same. Tommy, how thin do you make it? 1:1 or so?

I thought the drying time was ~3 hours but actually the coating was much harder this morning after drying overnight. Still pretty thick, though, so I'll try it again.

Thanks for the help!
hi patrick i have the cortec and works well you have to thin it with water `15-25 dilution and use a brush joe
My original understanding was to thin it with water also, and it worked well with my project. It always seemed contrary to thin it with the very stuff you use to remove it if needed.
Hmmm, well, paints are pigments dissolved in solvents. For example, latex paint, which uses water as a solvent, is thinned with water. So I'm not worried about that.

I thinned my Cortec 50% with denatured alcohol and it went on great with a foam brush.

Thanks for the replies,


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