Please help me before i go insane... After every infusion i do (practcing on glass using carbon fibre and plain weave e glass) There are small gaps between every tow in the weave. I have tried everything i can think of to stop this. I am using carbon that is stored in bubble wrap, epoxy infusion resin, i acheive full vac and no loss of vacuum. As i do it on glass i can see where the problem lies.... During infusion it works perfectly, but as soon as i clamp the feed line small voids form in the weave. I also de gas the resin for 10 minutes first. Any help would be very much appreciated.

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How do you define full vacuum? The only meaningful definition, in this case, is absolute pressure - not gauge pressure. Absolute pressure is measured relative to a perfect vacuum (zero is a perfect vacuum), and requires a special gauge like a U-tube manometer. Gauge pressure is measured relative to ambient atmospheric pressure (zero means no vacuum), and is what most gauges measure.

There are two reasons for your pin holes.
1. Residual air in fibers tows that were encapsulated by resin flowing through the weave openings. After resin plugs the vacuum port, no more air can be removed. Capillary action causes resin in the weave to wick into the tows, displacing the air into the weave openings. The solutions are use a better vacuum (so there is no residual air to trap), or to slow down the infusion so that the wicking of resin into the tows closely follows the flow front through the weave (so the resin can push the residual air out the vacuum port).
2. You may be boiling the resin by applying too much vacuum after you close the resin inlet. Resins will always have some volatiles (including the resin itself). After closing the resin inlet and the vacuum line is full of resin the vacuum should be reduced to 10 inHg. This provides 10 inHg of compaction pressure on the fibers while maintaining 20 inHg on the resin during cure.

When you reduced the vacuum you apparently allowed air to flow back through the vacuum line into your laminate. The vacuum line needs to be full of resin and remain full when you reduce vacuum. You should be able to see this through a transparent plastic line. With VARTM the big problem is that during infusion the area around the resin inlet will become very resin rich and thick because of high resin pressure relative to the area around the vacuum line. When the inlet line is closed the expectation is that the thickness will equilibrate throughout the panel. It is the "sponginess" or compressibility of the fabric that controls the panel thickness in concert with resin content and viscosity. Viscosity resist flow and therefore resin pressure can vary from one area to another. Resin pressure plus fiber compaction pressure is always equal to bag pressure (which is ambient air pressure). And thickness is directly related to fiber compaction pressure.

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