"Dave Allyn" wrote Even if I use the correct
hardner?

Example: I use 1.5 Gal kit from Raka. I run out, and so order a pint
kit from system-3. I use the S3 resin with the S3 hardner. will it
bond okay to the Raka resin, that was mixed with the Raka hardner?

I believe the answer would be "kinda, sorta". If the original layer is
cured, clean and lightly sanded the new epoxy will bond very well but I
would not do it on highly stressed parts. Flexibility of the cured resin
varies considerably. I have found Raka to be a bit brittle compared to
System3 and bulk brands like FGCI's laminating resin to be considerably more
flexible. If all the coats don't yield at the same rate the ultimate
strength will suffer..

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
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