Finishing Epoxy coat

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Finishing Epoxy coat

Author	Message
franckG31	franckG31 posted 10 Years Ago HOT Topic Details
Group: Forum Members Posts: 3, Visits: 8	When I apply Clear Epoxy on top of the parts I make, it often runs of from some areas ? Any idea on how to prevent that ? I tried degreasing the part with alcool, it was worst than ever.
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Dravis	Dravis posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 592, Visits: 1.9K	Use a "coating epoxy" that has some thickening agent in it, to prevent it from sagging and running off. Also paint on a very thin layer then wait until it is almost hard, but still a bit "tacky" in the surface, then paint another thin layer .. keep going until you have the desired thickness.. If you leave the thin layer to cure fully, then you must wet-sand the surface carefully before applying the next coat. "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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Fasta	Fasta posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 468, Visits: 3.5K	West system 105/207 Epoxies are also very sensitive to surface contamination so make sure the surface is wiped off with a wax and grease remover. Fastacraft Facebook page
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FalleN	FalleN posted 9 Years Ago HOT Post Details
Group: Forum Members Posts: 2, Visits: 74	Hello guys, sorry to kick this topic, but I figured it was better to do this than to create a new one. I have been working with carbon wet layups / laminting (just for show, covering an original part) for half a year now. I've gained some good progress with how to use the stuff and such. But there is one problem I can't solve. After brushing down a nice smooth layer of epoxy it all looks great, smooth surface, just how you would like it to be --> minimal sanding. But after a couple of minutes the epoxy starts to form a ''crater'' like surface. How does this happen? My prep work is: slightly sand it with scotchbrite, degrease with aceton, warm up part to ca. 18-20 degrees, warm up the epoxy to the same temperature. After that mix and apply thin layers with a brush. On a failed piece I've tried pouring a large amount of epoxy on the part and spreading it with a creditcard. This result is so much smoother, but it's harder to control where the resis is going to and results in more sanding work on the edges.
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Hanaldo	Hanaldo posted 9 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	That's too much surface tension caused by not having adequate adhesion. Basically you haven't abraded or cleaned the surface well enough. Given you said you only lightly rub the part with scotchbrite, I'd say this is your issue. Epoxy (all laminating resins for that matter) require a very good key. I would recommend 120 grit as a maximum, preferably 80 or 60 grit. And be sure to completely scuff the surface.
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FalleN	FalleN posted 9 Years Ago HOT Post Details
Group: Forum Members Posts: 2, Visits: 74	So I should scuff the previous epoxy layer up with 80 grit before applying a new layer? Seems to rough to me, but I'll test it. I hope it won't affect the physical appearance of the parts, since these are for show on a car. Thanks for the response
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