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Raka seems to take longer to cure
By:Tom
Date: 4/3/2002, 5:41 pm
In Response To: Epoxy: Glassing the hull (Scott)

I just tried some Raka for the 1st time several weeks ago. I used it for the final fill coats on my Guillemot. I like it better than the "other stuff" I was using for several reasons. First, it seams to aquire less air bubbles when mixing and rolling. It worked way better than rolling the other brand epoxy, OR maybe my technique has just improved. The second thing is the long pot life. Even with 1/2 slow and 1/2 fast hardner, the working time was much longer than just the slow of the other brand. This can be a problem for impatient people though. Experimenting with just the slow hardener, it took about 14 hours at 72 degrees to get to the non-sticky-don't-leave-fingerprints-point.

With just the fast hardner, the residue left in the mixing cup was still flexible at least 3 days later. This surprised me because by this time, the other brand had always set hard and very firm...you could break or snap it apart. The Raka would just bend.

This stuff seams to take much much longer to fully cure. Two weeks went by without touching the first fill coat. It still had a pliable nature, but it scraped nicely. I think it would quickly gum up sand paper. I could definately still smell the stuff. Since I am working in my appartment, every day I run a box fan in the window to exhaust the stale room air and replace it with fresh air by cracking a window at the other end. The only problem with this technique is there is always a bit of dust getting into the epoxy, but it cleans up quickly with a scraper or a light sanding. Also the furnace needs to run a lot. Most of March we still had below zero in the evenings and highs of 10's to 20's.

I would think that I should wait about 3 to 4 weeks before applying any varnish since its obvious the stuff is still curing after 2 weeks.

Any other thoughts or comments to what I have noticed are encouraged.

Thanks

Tom

Messages In This Thread

Epoxy: Glassing the hull
Scott -- 4/2/2002, 10:55 pm
Raka seems to take longer to cure
Tom -- 4/3/2002, 5:41 pm
Re: Raka seems to take longer to cure
John Skinner -- 4/3/2002, 8:52 pm
Brand X
Tom -- 4/3/2002, 10:38 pm
Just let it sit a bit. It gets harder in time
Paul G. Jacobson@aol.com -- 4/2/2002, 11:34 pm
Re: Epoxy: Sounds Good!
Rehd -- 4/2/2002, 11:13 pm
Re: Epoxy: Sounds Good!
Scott -- 4/3/2002, 10:31 pm