Talk Composites - The Forum for Advanced Composites

Cloudiness and white specks in finished project

http://www.talkcomposites.com/Topic3480.aspx

By SRTCobra - 11/21/2012 12:46:28 AM

Hey guys!  I'm new to the forum, and new to composites in general.  My first project involved using a Red CF/Kevlar Fabric to hand lay up some side Moldings on my Jeep Grand Cherokee SRT8.  It took me a couple tries to figure out how to get it to stay tight on the part, and wait for the perfect time to lay down the cloth.  I finally got that down, and thought I was doing everything correctly.  Followed all instructions, advice, etc.  Anyway, after I got the finish perfectly smooth and scratch free, I looked at all four panels in the light and to my disgust, it was cloudy in the majority of places, with little white specks everywhere.  I don't know what I did wrong to get this cloudiness and specking.  It also looks like it goes all the way through to the CF weave.  I'm dumbfounded and don't even want to try again, if after all that hard work it's going to come out looking like this again.  I posted a picture of what I'm talking about.  It does not show the white specking, but you can see the cloudiness, especially towards the right.  And unfortunately this is not the worst one.  Any advice?
Thanks in advance,
Cody



White Specks
By matthieutje65 - 12/10/2012 2:57:51 AM

Hi,

I had the same problem a few times, things I found out that might help you:

1. Your epoxy had some tiny bubbles 
2. Curing environment with to much humidity
3. Sanding to early (wet sanding with moist)
4. Thing I recently found out; Carbon fiber for example absorbs water. So if you store it in "bad" conditions; water inside your carbon will react with the epoxy.
    you can solve this by putting your carbon in the oven for a while.

hope those few point might help you in the future Wink