Hey Just wondering how many of you are glossing your epoxies with polyester resin. I have done both a poly gloss and an epoxy gloss but still dont think the bond between the polester and the sanded epoxy hotcoat is good enough.
It certainly becomes a mechanical bond vs. a chemical bond; you have to sand the previous epoxy application and clean up with denatured alcohol. It will bond just fine. I’ve done this and have consulted other who have done it with great success. You may find contradictory information in this forum, but it works just fine.
I did my polyester hot coat over my epoxy lamination and it came out great…the hot coat came out so well that I was able to sand from 100 grit to 600 grit (wet) and did not need to do a gloss coat which saves on weight, labor and money.
I did the polester hotcoats and they do chip off over time. Some Quicker than others but its a nightmare when it happens. That is why I am afraid of the gloss coats
You may have more experience than I do; the immediate results of my board appear pretty solid. I was very careful to sand all the shiny spots before applying the hotcoat, hopefully it will hold up.
Gary
Don’t let it scare you, I have stopped using polyester on all of my wood boards. Poly shatters way too easily and with a good sand job the polyester gloss resin from Reichold bonds very well with Resin Research epoxy resin. Of course it DOES NOT bond as well as a poly2poly, but in field testing at Malibu, with the wood boards sliding up the beach and into cobbles, there was very little shattering and only one spot that had any chipping. Even that one spot had adhesion next to the ding. Proofs in the pudding, pudding them to use
Newbie question - but wouldn’t glossing with polyester over epoxy pose a problem if you subsequently get a significant ding; and, when doing the repair if any poly hit the eps/xps foam it would melt? I understand it would be important to repair the layer adjacent to the eps/xps foam with epoxy but there is a chance some ply could seep into the foam when doing the hotcoat. Much ado about nothing…
But I’m sure the poly gloss looks much nicer than a RR epoxy gloss coat. Thanks.
For what it’s worth ~
Though mixing materials always creates a week link,
nothing polishes like Polyester!
Wanting what’s pretty I can see why some go with it.
If you want practical and servicable stay with one material.
The best way I’ve found to get a nice bright finish on epoxy is to get a good clean fill coat on the board that can be worked out well without exposing any weave. A second coat after sanding the first fill coat to 120 works grand. Thank goodness for Additive “F”! Obviously shine is more important than finish weight when you choose the get highly glossed finished board. Once you get that good surface on the board sand it from progressively 320 to 1200 then polish it like it was a poly board. Finally get out the release wax and mix it with a good high grade auto wax. Apply a couple of coats of wax to the board and you’ll have a pretty nice finished product that’ll never chip off. It’s quiter easily renewed as well.
Off to baste the new 8’8" Source Quad.
Mahalo, Rich
Well for one, why would the gloss resin come into contact with the foam, not how I build boards anyway.
Aloha Genius,
Just when I thought you were one of the last hold-outs on poly resin on wood boards, you’ve convinced me about using epoxy. Since I know your work first hand, I know you strive for excellence. Can you get that classic high gloss finish with the poly gloss over the epoxy?
richard
Don’t worry -
Poly resin will only melt EPS as a liquid - when cured it’s fine.
You should be doing repairs with epoxy as well, sanding the poly off before hand, well back from the area.
But anyway, you should’t have to use poly when theres a much better way…
But you have to have a spray gun and compressor.
Sand your epoxy hot coat/filler coat to about 220 grit.
Spay with 2 pac automotive clear coat polyurethane.
Don’t tape off the rail like you do for a hot coat though. Let it fade out naturally.
Wait till dry, flip board over, spray other side. Wait til dry.
Then wet-sand (lots of water) with 1500 grit.
Then rub with a cutting compound paste, one thats meant for cutting new automotive paint.
Then buff 'til your hearts content.
You’ll get a shine like you see on a show-room ferrari, and your epoxy is now UV protected by the most technologically advanced sh**t on the market.
How long does it take a car, sitting in the baking sun all day, every day, until the clear coat paint comes off? 5 - 10 years? even in california?
Stone chips happen on cars, but thats a pretty serious impact… I’d make the call that the paint adds impact protection too.
You can cover places where you accidentally sand through to the weave, without even re-coating with epoxy!
You don’t even need a very clean spray booth, as the wet sanding can remove heaps of “fall-out”, the grit that lands on your freshly sprayed paint.
But theres a catch - get a “liquid” shine, and when you hit the water, you find that your boards much more slippery than your used to!
I’ve buffed with car wax before, it looks incredible, but it takes a surf or two before the slickness goes away.
Thats what happens when you get a finish that perfect though. just like a wet tile floor. You get used to it though.
Kit
Oh believe me, I would really prefer to be spraying clear coat enamel for a finish and had done it 20 years ago for epoxy.
BUT, without a completely LEGAL spray booth here in SOUTHERN CALIFORNIA, it would be tantamount to ask for a citation by air quality nazi’s. We are walking on egg shells already, waiting for the axe to fall
Ah, I see your point!
That stuff is so nasty to work with anyway!
Kit