Skinning raw metal

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Skinning raw metal

Author	Message
pedcrist	pedcrist posted 12 Years Ago HOT Topic Details
Group: Forum Members Posts: 42, Visits: 350	Hi I need to skin a motorcycle fender with cf, but it is in raw metal. Do i have to aplly some primer first, to prevent the appearence of rust? Pedro
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Matt (Staff)	Matt (Staff) posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 680, Visits: 1.9K	Hi Pedro, No, you should be fine to apply the skin of carbon fibre direct to the metal; in fact the epoxy should act as a primer, ensuring that water cannot reach it. Ensure that there are no areas that are not covered by the resin otherwise these may be a point where corrosion could start but providing the metalwork is completely covered in the epoxy (used for the carbon skin) you should be fine. Best regards, Matt 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	Matt (Staff) (03/12/2012) Hi Pedro, No, you should be fine to apply the skin of carbon fibre direct to the metal; in fact the epoxy should act as a primer, ensuring that water cannot reach it. Ensure that there are no areas that are not covered by the resin otherwise these may be a point where corrosion could start but providing the metalwork is completely covered in the epoxy (used for the carbon skin) you should be fine. Best regards, Matt Hi Matt, That was good timing because I was wondering about this too. Would you say it was better to apply the carbon to bare metal or if the metal panel was already painted would it be ok to just key the surface and apply the carbon? Would the epoxy bond be greater to bare metal as opposed to the paint? Many Thanks Marc
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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, The bond would be better to bare, keyed, metal than it would to the plastic of the paint. Likewise, I would say that the bond of the epoxy to the metal would also be better than the bond of the paint to the metal too so if you have a choice then bare metal is the way to go. --Matt 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	Matt (Staff) (04/12/2012) Hi Marc, The bond would be better to bare, keyed, metal than it would to the plastic of the paint. Likewise, I would say that the bond of the epoxy to the metal would also be better than the bond of the paint to the metal too so if you have a choice then bare metal is the way to go. --Matt Thanks Matt :-)
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Jack.Strong	Jack.Strong posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 52, Visits: 549	etch the metal
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Kevin-Lee	Kevin-Lee posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 44, Visits: 2.4K	Hi, You would not need to etch the metal because epoxy will form an ionic bond with the bonding surface... This is the very reason epoxy exhibits superior adhesion to most materials/substrates and also the very reason that epoxy primers/paints are recommended for "direct to substrate" application... The most important factor would be that the surface is clean and residual free, a key with a scotchbrite also wouldn't hurt... Kev. Edited 12 Years Ago by Kevin-Lee
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pedcrist	pedcrist posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 42, Visits: 350	Thanks, Matt and Kevin-lee. Pedro Edited 12 Years Ago by pedcrist
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Matt (Staff)	Matt (Staff) posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 680, Visits: 1.9K	You're welcome. i'll second what Kevin says, I don't think etching would be neccessary, a mechanical 'key' and a clean, degreased surface are the priority. 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	I've just skinned a bare metal bonnet with 1 layer of 200gm plain weave CF, unfortunately I can now see lines of the silvery bonnet through the weave of the CF. I did not apply a black pigmented coat of epoxy on the bonnet prior to laying on the CF because that makes the CF very hard to place perfectly due to it's tackiness. I'm wondering what is the best way to proceed.... 1. Give the bonnet a really good sanding with 80 grit and apply another layer of CF? how good will the bond be between the new and existing layers of epoxy resin? 2. Try and remove the CF from the bonnet and start again. and go back to my previous method of using a black epoxy primer on the bonnet first? Any other ideas?
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