Talk Composites - The Forum for Advanced Composites

Any tips for achieving a "clean" break line while carbon skinning?

http://www.talkcomposites.com/Topic713.aspx

By GEARHEAD - 2/15/2012 3:43:07 PM

 Do any of you clever composite fellows have any ideas on creating a clean break line between a carbon skinned surface and a plain (painted) surface? I attempted masking with tape an area I did not want skinned but came to the quick realization that the resin would slightly cover the tape and not allow me to remove it. BAD PLAN !!!  
   All I know to do is to cure my carbon area, blend the nasty edge the best I can then repaint the area next to it. 
   Also would like do a motorcycle windscreen the same way (glass upper and carbon lower) but getting that break line attractive is not currently workable. 


Please advise,
     GEARHEAD
By Bruce - 8/5/2012 1:18:33 PM

Is the part already painted ? , 
You could mask of the edge where you want the break line with flash tape 3 layers or so then sand the paint off  up to the tape 
then apply your carbon slightly over the flash tape and bag it and cure it as normal .
when its cured carefully sand down the carbon that covers the flash tape 
once you have removed carbon down to the flash tape you can peel the tape off leaving a sharp break line in the carbon 
I do this when repairing carbon parts with visible weave 
i look for the manufacturers join lines in the part and repair to these joins
on the carbon parts i remove the laqueur up to  the break and 1 layer of carbon replace the layer of carbon with a new one 
i then laquer the fresh carbon up to the break cure it ,flat it then re-laquer the whole part 
this gives a very neat edge 
it may be worth a try 
i have some pictures of this here