Skinning raw metal

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Skinning raw metal

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Matt (Staff)	Matt (Staff) posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 680, Visits: 1.9K	Hi Marc, OK, yes, that's an unfortunate lesson you've learned there which is that a single layer of carbon laid over something (particularly something bright like bare metal) will show through the original part. What I would suggest you do now is to remove the skin completely with a power sander and start again. Black Epoxy Basecoat is a good idea because epoxy bonds famously well to bare metal. You could use black paint but that bond wouldn't be as good as the epoxy basecoat would be and so it would create an unlikely, but possible, failure point. This failure point would only be likely to be evident if the metal part became hot and expanded (which the carbon skin would not) which puts a lot of stress on the bond line. All the best, Matt Matt Statham Easy Composites / Carbon Mods - Technical Sales Tags basecoat carbon fibre gaps skinning
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marc37i	marc37i posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 16, Visits: 566	Matt (Staff) (18/12/2012) Hi Marc, OK, yes, that's an unfortunate lesson you've learned there which is that a single layer of carbon laid over something (particularly something bright like bare metal) will show through the original part. What I would suggest you do now is to remove the skin completely with a power sander and start again. Black Epoxy Basecoat is a good idea because epoxy bonds famously well to bare metal. You could use black paint but that bond wouldn't be as good as the epoxy basecoat would be and so it would create an unlikely, but possible, failure point. This failure point would only be likely to be evident if the metal part became hot and expanded (which the carbon skin would not) which puts a lot of stress on the bond line. All the best, Matt Hi Matt, Thanks for the reply. The reason I'm trying to avoid using the Black Epoxy Basecoat is, aren't you suppose to lay the carbon on that once the basecoat reaches it's b stage ie still tacky(ish)? the problem with that is,trying to place the CF on the basecoat, if you dont lay it down perfectly first time it's so easy to get distortions in the weave. That's why I thought using black epoxy primer(not ordinary primer) may be a good solution, it would be dry when I'm laying the CF down, so easy to reposition and get right. Also epoxy primer bonds to the bare metal better than ordinary automotive primers. But what I'm concerned with is the epoxy resin to epoxy primer bond, I thought epoxy to epoxy bonds were very good, is this not the case? Regards Marc
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Matt (Staff)	Matt (Staff) posted 12 Years Ago Post Details
Group: Forum Members Posts: 680, Visits: 1.9K	Epoxy bonds to epoxy when the epoxy you're bonding to is in the 'B' stage of its cure; this allows the fresh epoxy to cross link to the 'B' stage cured epoxy and make a strong chemical bond. Once the first layer of epoxy has fully cured, the cross linking won't happen and the new epoxy will only be able to make a mechanical bond to the first layer of epoxy which is less strong so, although it bonds well (given the appropriate surface preparation/key) it won't be as strong as a bond to 'tacky' (b stage) epoxy. Matt Statham Easy Composites / Carbon Mods - Technical Sales
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marc37i	marc37i posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 16, Visits: 566	Thanks Matt
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mhdghoul	mhdghoul posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 49, Visits: 113	number 1 is gr8 as an option ,u dont have to go through the headeack of removing it, conside it as a great primer ,u may use the black base coat i think it will show nothing like metal below , hope this is fruitfull bye best regards mhd alghoul mhdghoul@hotmail.com youtube channel :atmospherejo link is http://www.youtube.com/user/atmospherejo?ob=0&feature=results_main
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