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Epoxy Cpes, raka, west,fgci

PostPosted: Fri May 29, 2009 11:17 am
by Dan & Julie CO
Hello all, I am building a 4x8 tear and not wanting to spend more than needed. Does anybody know about how much it will cost covering 2 coats of epoxy and is there a product less expensive than another?
I hear some using exterior primer and paint with no epoxy is that a mistake
I am not building the Taj mahal but don't wanna short change myself
Thanks :thinking:

PostPosted: Fri May 29, 2009 2:05 pm
by Esteban
A 3 gallon kit from Raka, or another supplier, will be more than enough epoxy to cover a 4 x 8 on the sides and roof. You could take a chance it'll be enough and use a 1-1/2 gallon kit. Are you planning on painting over the epoxy or skinning with aluminum? If you're painting and want a nice smooth surface using a quality sanded plywood can save epoxy used for filling roughness or fairing.

PostPosted: Fri May 29, 2009 3:31 pm
by Arne
exterior primer and paint results in a mediocre looking tear that dirtys easily and is very difficult to clean. Marine paint, at about 2-3 times the cost will give you a great finish that lasts for years.

It also will not seal well. Most primers will barely soak in to protect the wood. I still suggest cpes or thinned out epoxy followed by marine primer/paint.

PostPosted: Fri May 29, 2009 8:16 pm
by Dan & Julie CO
Comes down to "Good money after bad" if I do it right the 1st time I won't
have regrets. My plan is to skin with 5.1 mil laun smooth finish and go the
Marine paint route for covering.
1 1/2 to 3 gallons seems like alot :? Does the CPES require as much?
I was under the impression it would be around a 1/2 gallon per coat where
I got that impression I couldn't tell you, maybe pictures of 1 to 1 in quarts. :)

PS I started installing spars Put a few progress pics in my album

PostPosted: Sat May 30, 2009 6:52 am
by bbarry
Larry from RAKA recommended the 1.5 gallon kit for my 5x9.5. That has allowed me to bond 8 5x5 sheets of plywood, coat the entire trailer, and do a small amount of fiberglass repair on my mower body. I definitely recomend mixing in small batches to keep the epoxy fresh and using a squeegee spreader rather than a brush. It will make the epoxy go twice as far.

Yes, it seems expensive, but it's not that big a cost in the long run. Have fun!

Brad

PostPosted: Sat May 30, 2009 7:28 am
by madjack
...a gallon and a half SHOULD be enough...remember that epoxy will last practically forever on the shelf, so you don't havvta worry about it spoiling...some additional tips...it will take 3 coats to fully seal wood with epoxy...VERY IMPORTANT, be sure to round off any sharp corners/edges as the epoxy/primer/paint combo will crack along a sharp edge...seal all edges, especially well...a filler or sawdust can be added to the epoxy as a thickening agent to fair out edges while sealing them...epoxy with a marine topcoat paint (InterLux Brightsides comes to mind) is an excellent way to finish your tear...regular house primer/paint is not...your finish will only look as good/smooth as the substrate underneath does...take your time...use small batches at a time(no more than a quart)...when doing additional coats with the RAKA, you need not sand if applied in less than 24hrs...if over 24hrs, you will need to sand before additional coats can be applied...while epoxy can be spread with brushes/squeegees, I find foam rollers work the best...use plastic tray liners and gototown withit..........
madjack 8)

PostPosted: Sat May 30, 2009 7:47 am
by Arne
a minor explanation. If you do the additional coat before the 24 hrs m/j mentioned, you get a chemical bond as the epoxy has not completely 'hardened'... after 24 hrs, give or take, the bond will only be mechanical, thus the reason for sanding.

PostPosted: Sat May 30, 2009 8:04 am
by Dan & Julie CO
Wow very informative I'm planning to use durhams water putty for filler mostly because I have some already will the epoxy penetrate ok?

PostPosted: Sat May 30, 2009 9:43 am
by madjack
Dan & Julie CO wrote:Wow very informative I'm planning to use durhams water putty for filler mostly because I have some already will the epoxy penetrate ok?


...dunno...never used it, myself...you might ask Larry at RAKA or the tech people at Durhams about compatibility issues...hmmmmmm :thinking: another thought...I wonder if you could mix the dry "putty" powder(gypsum) with the epoxy to make a water proof filler/fairing agent...........
madjack 8)

PostPosted: Sat May 30, 2009 10:05 am
by Juneaudave
madjack wrote:
Dan & Julie CO wrote:Wow very informative I'm planning to use durhams water putty for filler mostly because I have some already will the epoxy penetrate ok?


...dunno...never used it, myself...you might ask Larry at RAKA or the tech people at Durhams about compatibility issues...hmmmmmm :thinking: another thought...I wonder if you could mix the dry "putty" powder(gypsum) with the epoxy to make a water proof filler/fairing agent...........
madjack 8)


Indeed...You can mix Durhams with epoxy to make filler!!! Check out theOne Ocean Kayak page on filling. They use a mix of Durhams, microballoons and wood dust. It works really well...
:thumbsup: :thumbsup:

I used a gallon and a half

PostPosted: Wed Jun 03, 2009 8:40 pm
by joe43952
I used a gallon and a half on my 5x5x10. It worked out just fine with 3 coats. I used west system just because I have a west marine store close to me. It saved on shipping.
Image

PostPosted: Wed Jun 03, 2009 11:21 pm
by kennyrayandersen
Durhams -- is that the one that says Rocky says Rock hard on the outside? :lol:
That's the one we used to use -- kind of a pale yellow color.

PostPosted: Thu Jun 04, 2009 7:48 am
by Dan & Julie CO
Yeah the light yellow putty stuff on the can is muscle dude flexing his guns :lol:
thanks joe the paint you used looks great looks like auto paint