1st insfusion problem in a looooong time..

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#1

Alright guys, so I had two failed parts that failed at the same time. We have not had a failure like this in a long time. So I’ll first explain the laminate, then the problem.

Two molds roughly 11" wide by 38" long with a 2" raised lip all around. They are door sills. I laid in two layers of 6oz carbon fiber, one layer of 1/8" inch core matting, and one more layer of 6oz carbon fiber. One layer of nylon release peel ply was added and green flow mesh.

On the first mold I had a vacuum line attached on the right side of the wider end of the mold. Off the left side of that same mold there was a tube going to the second mold. On the other sides of the molds were 3/8th inch infusion lines.

I infused at full vac and then noticed there were many pin holes in the bags. Not sure how they got there, but I plugged them all up. Or so I believe…

The problem I had was that the resin just would not flow. I’ve made the same parts many times with the same resin and never had problems. The resin just would not flow. It saturated, but didn’t flow.

My guess is that there were still a few pin holes in the bag and that somehow didnt allow the resin to be vacuumed into the mold? Could that be a proper assumption?

#2

Plausible.

Do you have a vacuum pump that switches off when a certain level of vacuum is reached?

any other parameters changed? Materials? Temperature?

Leaks can greatly influence the resinflow, that is for sure.

#3

All I can say is that it’s a really weird day…I had exactly the same problem everything seemed alright - peel ply - flow mesh- full vacuum but the resin wouldn’t flow… I call it off for today…

#4

high humidity in the air

#5

I was infusing in a climate controlled room. Temperature was 75 degrees. Resin was an ISO tooling resin that we’ve used hundreds of times before for infusion. The only thing different was I was using a core material. I infused the same panels with the same core material a few months ago and had no problems. Like I said, there was no problem with saturation, just with flow. The last change was I was using the MTI hose but I stopped half way through, removed the MTI hose, and there was no change.

A few days prior, we infused a rear bumper insert for the TT RS with the MTI hose and we had no problems.

#6

Nope. We are using your regular Harbor Freight red pump. It hardly ever lets us down. When it does, we go in and exchange it under warantee.

#7

It was a weird day. On the drive home I turned on the cruise control in the Camaro and the throttle reved till it hit red line. If anybody else has that same problem let me know! Its a 2010 Camaro SS.

When I got home I found out that the internet modem was malfunctioning too.

Hmmm…

#8

?? Just call it a strange day I guess, I see no reason why the resin didn’t pull, even on weak vacuum it should still pull, the lay-up was not stacked to the point it would effect the flow ratio…

G/L

#9

…well check you bagging material, again. I have seen that happen before, for no reason at all right in the middle of the roll, -holes- small, big, gouges, etc. I’m not even going to speculate on the infusion, as I know very little about it.

Core material–I have seen this do strange things as well. I have seen core make a part look like a bag leak part, and that was using autoclave/prepreg stuff. most times it was because of pressure was set too high.