Infusion: Air in the feed hose getting trapped in laminate..

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#1

The air in the resin feed hose gets sucked into the laminate when you release the clamp to begin the resin infusion. On a couple of small parts, it appears the air has gotten trapped against the mold and left pinholes and larger voids in the laminate. Has anyone else noticed this, and what was your fix? My resin viscosity is around 300 cps and I have a full vacuum on the part with no leaks.

The reason I suspect it’s the air in the feed line is that the number and size of the pinholes gradually decrease the farther you get away from the resin feed.

TIA - Bob

#2

sounds to me more like the air is getting in there at the end of your infusion, not at the beginning… the vacuum will pull the air out before infusion starts, but if it happens at the end, you’ll get air caught in the resin, likely in higher amounts near the feed point and dissipating from there

#3

I agree in principal, but that’s not what’s happening on these parts. There is absolutely no air getting in from anywhere other than than small amount that is in the feed tube before the resin gets sucked in.

At the end of the infusion, the resin line gets clamped off securely and the end remains in the container with the excess resin. There’s no chance for air to get in. I have multiple gauges that all verify that the vacuum is constant and there are no leaks before, during and after the infusion.

#4

I have the same thing happening and the only bubbles you can see are
little ones were the fibres are weaved. still looks okay though.
also there are bubbles aroung the flow media after the resin is all in and there is 29.9 hg ???/
I d like to know to some solutions

#5

The only thing I can think of is the infusion process went too quick and all of the air traps did not completely get infused by the resin before it reach the end point. Try using less of the flow media and see if that helps.

#6

that is the only thing I can think of as well is to use less flow media

#7

I think that I need more flow media because the resin isn’t going all the way to the vac portand not saturating all the fibre???/
Could also be that the resin is gelling to fast.to (much catylist)

also I should be able to use the same resin weight as the fibre weight???50/50
mixxing a little more for when the resin goes down in the cup and close to the bottom, clamp off line so that it dosn’t suck air ?//

thank for advice…merry xmas happy new year all…