Milky spots on my carbon fiber part

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Milky spots on my carbon fiber part

Author	Message
N1ck	N1ck posted 12 Years Ago HOT Topic Details
Group: Forum Members Posts: 6, Visits: 61	Hello guys! I'm a newbie here. I just start making parts from mold and run into this problem. After I demolded my part, everything looked perfectly, no pinholes whatsoever except this milky spots on my parts. I've posted some pictures below. What is the cause of this and what would be the best solution? Thanks a lot guys.
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ajb100	ajb100 posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 346, Visits: 4.4K	Did you use gel coat? Was it infused or wet lay? It looks like air trapped between the fabric and gel coat
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N1ck	N1ck posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 6, Visits: 61	No, I use epoxy resin. It was wet lay. I applied one light coat on the mold and wait til it became tacky to lay the fabric though. Can that cause this problem?
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ChrisR	ChrisR posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 363, Visits: 3K	it still looks like air bubbles though, maybe it wasn't worked in enough
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ajb100	ajb100 posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 346, Visits: 4.4K	That method can still cause bubbles trapped between that first epoxy layer and the fabric. You just need to apply that first layer a little resin rich and working it thoroughly with a roller. I prefer bristle rollers for woven fabrics as they seem to move the fibres around more. You can then do the following layers slightly dryer and the excess resin from the first layer will make up for it when vac bagged. As long as you've weighed out the right amount of resin for the fabric, you shouldn't have any problem
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Matthieu Libeert	Matthieu Libeert posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 955, Visits: 3.4K	I would go for airbubbles as well... or delamination while demoulding Matthieu Libeert Founder MAT2 Composites X Sports website: www.mat2composites.com
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N1ck	N1ck posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 6, Visits: 61	Thanks a lot guys. ajb100 I'll give it a shot next time. I might really have applied too much resin.
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N1ck	N1ck posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 6, Visits: 61	Guys, so I took a look at the part closely today. It looked to me like delamination... Did I pull it out from the mold too early or the basecoat wasn't enough?
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Matthieu Libeert	Matthieu Libeert posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 955, Visits: 3.4K	Probably to early or with a bit to much force?! if possible put your part in an oven before unmoulding for a few hours Matthieu Libeert Founder MAT2 Composites X Sports website: www.mat2composites.com
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kidpaint	kidpaint posted 11 Years Ago HOT Post Details
Group: Forum Members Posts: 99, Visits: 676	could the first picture, but moisture somehow? I am more asking then saying. I see delam in the second one but the cloudy look of the first reminds me of when I did a project on a super humid day and trapped moisture
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