epoxy coating resin issues

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epoxy coating resin issues

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benet	benet posted 13 Years Ago HOT Topic Details
Group: Forum Members Posts: 59, Visits: 373	I am having several issues using your epoxy coating resin as a top coat over a laminate composite layup consisting of wood and glass fibre. The outer layer of the layup is .6mm veneer which has a thin coat of infusion resin applied to it at the layup stage in order to give an even colour when the laminate comes out of the press. (previously some infusion resin had soaked through the veneer and given a patchy look to the outer surface even after the coating resin had been applied. The infusion resin is sanded with 120 wet paper and wiped clean with a clean damp microfiber cloth and allowed to dry before the coating resin is applied at an ambient temperature of 25 C. The application of the coating resin at 2 parts res. to 1 part hard. is made with the resin largely bubble free, it is pored onto the surface and spread with mini foam rollers (held and gently dragged, not rolled). I have tried thin coats ( 36g. over 0.2m.sq) and experienced a lot of fish eye which i can only resolve by continuously spreading the resin as it thickens and eventually sticks with a less than smooth surface and still with fish eye in areas. I have tried thicker coats ( 80g. over 0.2m.sq) and experieced very severe fisheye which can only be resolved by spraeding continuously as before in an attempt to make the resin stick. The result is a largely smooth surface but still with significant fish eye and a lot of milky whiteness due to the over agitation of the large amount of resin. Both thick and thin require significant sanding back to get to a clear flat finish and in this process (starting 180 grit wet going to 1200wet ) i get 2 even bigger problems. 1. Is the appearance of white patches in the resin that appear to be leaching something onto the surface of the resin. They cannot be sanded away and do not go away with the application of heat. Also they cannot take a coat of resin on top of them as the problem persists through the new resin. i attach a picture for your examination. 2. Due to the thin wood veneer it is immensely difficult to judge at what point to stop sanding in the attempt to get a flat surface and any "rub through" is pretty much guaranteed to damage the veneer beneath, and anyway i cant work out an effective way of adding another coat of resin with any kind of decent finish on a surface that has uneven patches of wood and resin. Any help would be greatly appreciated, at this point im thinking varnish ? or GC50 polyester gel coat ? Thanks ben Attachments IMG_20120704_203701.jpg (772 views, 383.00 KB) Tags coating fisheye fish white patches GC50
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benet	benet posted 13 Years Ago HOT Post Details
Group: Forum Members Posts: 59, Visits: 373	Further.. Is it possible that im my attempts to flat the surface with 180 wet i end up rubbing water into the epoxy ? creating a reaction and these white patches ? That is how it feels. The patches are not there before i start sanding. Is there a cure once this has started to happen ? thanks again ben
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epoxy coating resin issues

benet - 13 Years Ago

Further.. Is it possible that im my attempts to flat the surface with 180 wet i end up rubbing...

benet - 13 Years Ago

Hi Ben, Thanks for the detailed description of your problem. Certainly the epoxy coating resin...

Matt (Staff) - 13 Years Ago

Thanks for that Matt, its hopefully very useful. Things i may havegleamedfrom it and will try...

benet - 13 Years Ago

Hi Ben, Again, that's useful feedback. A customer (a professional sprayer) told me a story...

Matt (Staff) - 13 Years Ago

Hi Matt, Thanks again. By way of a recovery from my situation i proceeded to dry sand (not...

benet - 13 Years Ago

Hi Ben, [quote] One small thing, ive just contacted a old friend who has a paint shop and oven....

Matt (Staff) - 13 Years Ago

I can confirm Matt's story about the silicone in the air. Once I've coated a part with epoxy and few...

NikCFC - 13 Years Ago

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