Ensuring cloth & resin run right into tight corners.

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#1

I’m having a struggle when trying to make my resin & cloth run right into sharp corners of my moulds.

In the moulds I lay out my fabric, apply resin with a brush, spread it out with a squeege and then vacuum bag, again using a squeege to ensure the bag is pulling into the tight turns too. Still I’m having this repeated problem of effectively air bubbles along sharp turns in the finished peice.

Any tips/hints would be greatly appreciated as it’s a real (expensive) headache.

Alex

#2

Hi Alex… Welcome to the forum

I have had this problem with a few of my moulds in the past. I have found that making relief cuts in the peel ply/release film where the bridging is occurring has helped on some moulds but on another 2 I have had to make a caul plate out of Vinamold and place this on top of the breather and then vacuum. This cured my problem.

#3

its hard to get good compression in corners. Try using a rubber sgueegie in the corners while vac bagging the part. The best solution would be to switch to infusion.

#4

Thanks for the tips. I’m only going to produce one of these so I’m not too keen on more expense by tooling up to infuse.

Please could you explain caul plate to me though, I’m not familiar with the term.

I’m quite sad my last layup didn’t work properly, because if the edges were nice it would of been a cracker:

#5

Just a thought; As the problem seems to be the extreme tightness of the corners on my mould, if I were to apply with a fillet ball some epoxy filler to those corners would that make the problem less substantial?

#6

Yes, in addition to methods suggested above, filler is a commonly used method for tight radii

#7

As an alternative to filler, you could impregnate glass or even carbon tow. I have this in stock in 7,7 mm, but there are other sizes available.

For the rest: If your mold has flanges, then it is ready for infusion. But I would not start up another learning curve now.

#8

you dont need flanges to infuse a part, it is better to have though

#9

It is so much easier, especially when learning.

#10

I dont think its any harder, worse thing is the risk of a puncture in the bag on under side of the tool.