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Old 08-09-2014, 04:07 PM   #1
whitecel

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Default Composite Failure...Need Advice Please

Hey guys,
It's been a while since I've last been able to work on composites due to the flu, laryngitis, bronchitis, and now getting over shingles. Anyway, I decided to make the other side of my fork guard for my motorcycle today and the infusion looks to be a disaster. Did a 30 min drop test and it was fine. For some reason my dumbass thought that with the MTI hose you didn't need to degas the epoxy so I figured I shall try without degassing. I always degassed even with the MTI hose. So after I infused the part, about 30 min later, the bubbles seemed to be back flowing in the peel ply. Is this due to not degassing and the bubbles expanded when the epoxy was setting?

2 layers of 5.7 oz cf twill
2 layers 7.5 oz Matt fiberglass
Peel ply
Green mesh
MTI hose







Last edited by whitecel; 08-09-2014 at 07:24 PM.
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Old 08-09-2014, 05:11 PM   #2
Hanaldo

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I never degass.
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Old 08-09-2014, 05:23 PM   #3
whitecel

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But what caused the backflow? If there was no leak, I'm not sure what happened. The part looked completely saturated then when I closed the feed line, within 30 min parts of the peel ply became unsaturated. Hoping I get lucky and maybe all the bubbles lifted and underneath is still good.
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Old 08-10-2014, 08:58 AM   #4
DDCompound

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The bag became untight or was not tight. Looks like a very resin rich part, so even if you have not degassed you will get a much better result.
But on the first picture you can see the area i. front where the air came in, on picture two you see a dry area. That's the reason why you got that result.
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Old 08-10-2014, 10:29 PM   #5
whitecel

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So ow did the air get there if I drop tested and there was no leak? Trying to figure out how the air got in there
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Old 08-11-2014, 05:54 AM   #6
DDCompound

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Sometimes it can happen that the bag becomes untight after infusion. Most times it is a handling failure.
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