Filling in small holes on carbon fibre part


Author
Message
Lenny
Lenny
Supreme Being (133 reputation)Supreme Being (133 reputation)Supreme Being (133 reputation)Supreme Being (133 reputation)Supreme Being (133 reputation)Supreme Being (133 reputation)Supreme Being (133 reputation)Supreme Being (133 reputation)Supreme Being (133 reputation)
Group: Forum Members
Posts: 16, Visits: 58
After performing a resin infusion on my carbon engine cover am I left with a few holes in the surface.  Is there a repair process to fill these in ?  My thoughts are that I could mix some epoxy and hardener and simply fill in the holes and then sand/polish afterwards.  

just wanted to check if there is anything special tips/tricks that could help.



Regards,

Lee
MarkMK
MarkMK
Supreme Being (2K reputation)Supreme Being (2K reputation)Supreme Being (2K reputation)Supreme Being (2K reputation)Supreme Being (2K reputation)Supreme Being (2K reputation)Supreme Being (2K reputation)Supreme Being (2K reputation)Supreme Being (2K reputation)
Group: Forum Members
Posts: 338, Visits: 2K
Hi Lee

If it's bare carbon, with no in-mould coating, then you'll find it impossible to flat and polish any repair jobs up to the shine of the rest of the part. There's so little epoxy to work with that any shine is soon lost, I'm afraid.

 The only method that seems to work, if cosmetic appearance is key, is to fill the voids/pinholes with epoxy or some other priming product, flat and then spray with automotive clear coat

Others have found ways of spraying and filling in pinholes using a brush between coats, but all methods seem to require a fair bit of time and effort to do successfully

One further option is to use epoxy coating resin on the whole part, as this does respond to flatting and polishing, but it's time consuming work even on small parts, but achieving a good smooth application really helps. You might try applying with a roller, as brush marks are almost inevitable and two coats might also be necessary

I'm sure that others will chip in with their experiences too, though
fgayford
fgayford
Supreme Being (2.4K reputation)Supreme Being (2.4K reputation)Supreme Being (2.4K reputation)Supreme Being (2.4K reputation)Supreme Being (2.4K reputation)Supreme Being (2.4K reputation)Supreme Being (2.4K reputation)Supreme Being (2.4K reputation)Supreme Being (2.4K reputation)
Group: Forum Members
Posts: 433, Visits: 1.2K
Lenny (18/11/2015)
After performing a resin infusion on my carbon engine cover am I left with a few holes in the surface.  Is there a repair process to fill these in ?  My thoughts are that I could mix some epoxy and hardener and simply fill in the holes and then sand/polish afterwards.  

just wanted to check if there is anything special tips/tricks that could help.



Regards,

Lee


Hi Lee
Your talking about pin holes they are the curse of all composite work. I deal with them all the time.
This what I do.
1. lightly sand the whole surface and all the pinholes will show.
2.Wipe down with acetone or alcohol.
3. You must key or abrase each pin whole right to its bottom or things won't stick. I fold fine sand paper into a point and then twist when in the hole. Or a pointed dremel rubber abrasive bit.
4. If its tiny I will mix up some 2part automotive clear  coat and dab and work in the clear with an automotive touch up brush that looks like a toothpick with a tiny brush on the end. (ask automotive paint shop they will have them) Make sure you are proud of the surface.
5. Once completely cured wet sand flat.
6 If you have fixed them all, clear coat the whole part and you would never know you even had pin holes.

Fred 

  
Warren (Staff)
Warren (Staff)
Supreme Being (15K reputation)Supreme Being (15K reputation)Supreme Being (15K reputation)Supreme Being (15K reputation)Supreme Being (15K reputation)Supreme Being (15K reputation)Supreme Being (15K reputation)Supreme Being (15K reputation)Supreme Being (15K reputation)
Group: Administrators
Posts: 2.5K, Visits: 8K
Both the techniques above will work fine.

Whatever you do, the key is to make sure no dirt remains in the pinholes and ensure whatever filling product you uses actually gets into the hole. Otherwise the resin or paint will sit on the top then slowly sink in leaving a dimple and more work to do it fill it.

Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant
Lenny
Lenny
Supreme Being (133 reputation)Supreme Being (133 reputation)Supreme Being (133 reputation)Supreme Being (133 reputation)Supreme Being (133 reputation)Supreme Being (133 reputation)Supreme Being (133 reputation)Supreme Being (133 reputation)Supreme Being (133 reputation)
Group: Forum Members
Posts: 16, Visits: 58
Cheers guys, i will start the slow process of cleaning and sanding.

Regards,

Lee
GO

Merge Selected

Merge into selected topic...



Merge into merge target...



Merge into a specific topic ID...




Similar Topics

Reading This Topic

Explore
Messages
Mentions
Search