Dry patches using weave pattern

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Dry patches using weave pattern

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Philippine	P Philippine posted 6 Years Ago HOT Topic Details
P Group: Forum Members Posts: 4, Visits: 14	Hi, I am currently making carbon fibre samples of different layers and using different methods. I have managed to get a really good surface finish with hand lay-up but not with infusion (photo attached). I saw someone post a similar question on the forum but he was using unidirectional so our problem might be different. Following the videos you've made for infusion, the surface finish of all may samples are almost entirely dry as if there wasn't enough resin. You've suggested to reduced the flow speed to allow the resin to get everywhere which I will try very soon. However, my samples are pretty small (210x160mm) and I'm worried that it won't be enough. Could the infusion spiral be completely removed to allow a slower flow process ? Any advice would be greatly appreciated! Many thanks, Philippine
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Lester Populaire	L Lester Populaire posted 6 Years Ago HOT Post Details
L Group: Forum Members Posts: 311, Visits: 13K	+x Dromilious - 2/26/2019 11:08:36 AM +x Lester Populaire - 2/26/2019 10:36:27 AM +x dcfoster - 2/25/2019 11:30:55 PM Im having a similar issue, but its also leaving some of the epoxy on the mold surface. Ive added mesh to increase flow upon entry and created a resin break to slow down exiting epoxy into the catch pot. Also im using an infusion epoxy yet I keep getting dry patches. Im using a blue carbon/nylon cloth for the visible layer and then a +/- 45 biax for the underlayer. This is for a fuel door for an Acura. Ive never had this issue before, even with small parts but I keep getting it with this. Could it be since its winter that its too cold? I made sure to put my epoxy in front of a heat source to warm it up and noticed it gassed alot less when mixing, I also let it sit to degass for the 15min I usually wait to make sure the infusion molding is properly sealed and not leaking (the epoxy I use has a long pot life). Yet it only made less dry spots but still have them. Pics included. Original poster. sorry to thread jack, figured since you already have a thread open it just makes sense to keep all the 'dry fiber' issues in one thread. I would guess it's related to the spray tack. Either too much or a kind that does not dissolve properly in epoxy. To the original poster - could you share a picture of the vacuum setup? Normally this kind of things can be solved with the right infusion setup... i don't think it is from the spray tack. I don't use spray tack and i had once the same problem. I'm not saying this is the only explanation, but this is typically what i see when an intern is a little trigger happy with the spray tack on the first parts.
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