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Vacuum Infusion Problems, Requesting Opinions

http://www.talkcomposites.com/Topic30593.aspx

By d3ntr0n - 10/5/2018 4:36:35 PM

I have been laying up both CF and FG parts and trying many variations in my process in an attempt to produce a flawless part. I have been using Fibre Glast Series 2000 and Series 4500 resins and have similar problems with both. Regardless of how long I let the mold sit under clamped off vacuum and test the seal (I usually do 20 to 30 minutes) I still find pinhole leaks as the resin advances across the part as indicated by branching paths of bubbles.

How much of a problem do you think various trimmed pieces of infusion mesh, jacketed bleeder cloth, and sharp corners on a part are (90 degree corners). What can I do to improve my layup process?
By d3ntr0n - 10/15/2018 4:14:46 PM

 
Hanaldo - 10/7/2018 5:54:19 AM
Just clamp the vacuum outlet when the resin reaches it, then leave the resin feed hose for another 30 seconds (depending on how big/thick this particular part is; for parts bigger than 0.5sqm or 3mm thick then you might want to leave it open for up to a minute or so) before clamping.

So I tried this and it did result in an improved saturation. I clamped off the vacuum outlet and left the resin feed line open for 60 seconds before clamping it off. The result was good resin saturation for about 30% of the distance from inlet to outlet but the remaining 70% was still under-saturated.