coating epoxy hot coats

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coating epoxy hot coats

Author	Message
TomW059	TomW059 posted 9 Years Ago Topic Details
Group: Forum Members Posts: 6, Visits: 13	Hi, I have hot coated a kiteboard to test before doing it on a bigger job. I mixed coating epoxy and applied rather thickly with brush directly onto finished laminate ( 200g twill glass). It flowed out and filled weave nicely. After 18 hrs in 19c garage with controlled humidity, it is cured, but has waxy/ greasy surface. I tried cleaning an area with acetone and it did not help. I mixed using weight ratio with compensation for different density of hardener and epoxy. This,would mean I had a little too much hardener because it is lighter. Could this be problem. Epoxy is one year old. Been in cool dark place. It Looks clear and ok. Please advise, is this normal? I was expecting glossy, clear, hard surface. Regards, Tom Waldner
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TomW059	TomW059 posted 9 Years Ago Post Details
Group: Forum Members Posts: 6, Visits: 13	Sorry, I mixed using weight, Not compensating for ddifferent Densities.
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*VVS*	*VVS* posted 9 Years Ago Post Details
Group: Moderators Posts: 226, Visits: 334	From what ive read is Amine blush and you are supposed to be able to wash it off, with what I'm unsure, you could try washing up liquid. have a google about.
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TomW059	TomW059 posted 9 Years Ago Post Details
Group: Forum Members Posts: 6, Visits: 13	Yes, I Read up on this, it is amine blush and it washed off with soap and brush. But product us not supposed to get amine blush. Can easycompsites comment?
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Dravis	Dravis posted 9 Years Ago Post Details
Group: Forum Members Posts: 592, Visits: 1.9K	I often get Amine blush with EC coating resin ... It really needs rather high temperatures and low (very low) humidity to avoid Amine blush. Since I nearly always wet-sand and polish or clear coat, I just remove it in the first wet sand .. "Sapere Aude"... Dare to KNOW! The written word is the only truly efficient vehicle for transmitting a complex concept from mind to mind... 103% of all people do not understand statistics... Do not adjust our mind, theres a fault in reality :-)
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TomW059	TomW059 posted 9 Years Ago Post Details
Group: Forum Members Posts: 6, Visits: 13	Thanks guys, When you clear coat, are you wet sanding to 400? What clear coat are you using? My plan is to wet sand to 400, clean with denatured alcohol and clearcoat with International Perfection 2 Comp- polyuretane.
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Warren (Staff)	Warren (Staff) posted 9 Years Ago Post Details
Group: Administrators Posts: 2.5K, Visits: 8K	The standard mixing ratios for all our epoxy resins are based on parts by weight, so you will not need to take into account density and temperature in the weighing process. A minor change in the ratio could easily be the cause as could be humidity. You mention the humidity was controlled so it should not be that. The temperature is ok but higher the better. So that would suggest potentially a slight error on the mixing. A light wet sand and polish should remove any traces. Warren Penalver Easy Composites / Carbon Mods - Technical Support Assistant
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Dravis	Dravis posted 9 Years Ago Post Details
Group: Forum Members Posts: 592, Visits: 1.9K	Depending on the finish I want on the part, I normally sand to 600 grit, before clear-coating with 2-comp Polyurethane Marine varnish .. (Just because I bought a lot of that stuff at a silly low price.) If I use my "satin finish" 2-comp -- I sometimes stop at 400 grit wet sand- "Sapere Aude"... Dare to KNOW! The written word is the only truly efficient vehicle for transmitting a complex concept from mind to mind... 103% of all people do not understand statistics... Do not adjust our mind, theres a fault in reality :-)
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