Hoping for some help here.  My bagging is basically 50/50 ie one success to one fail. I'm making the bags using both the standard EC bag and the stretchy stuff depending on the part. I try to take a lot of care in making the bag and I feel I'm fairly precise with it but when do the vac drop test the needle will often pop up when I release the clamp.  Try as I can in terms of checking the tape and the bag, it's usually the case in a failure that all the pressing and checking will not find a leak, but there is one there of course.  Is there a device which can find a leak? I have tried everything including smoke to try to find a leak to no avail.

Hello

I had the very same problem when I first started infusions. I posted the fix some where on this site.

But in a nut shell this is where my leaks came from. The infusion mesh. It occurred to me that the cut edges of the the infusion mesh are sharp and they would puncture the bag every time. Not so much that you couldn't infuse, as long as you didn't shut the vacuum pump off. I was so frustrated that I thought that it was impossible to get a leak proof bag.The punctures were so slight that you couldn't track them down with a leak detector.

What I do now is cut strips of peel ply and lay it over every last infusion mesh cut edge under the bag as well as the spiral tubing. especially the ends of the tubes.

From the first time I tried this I have now had at least 14 perfectly sealed bags in a row and don't expect anymore. I once drew a full vacuum on a mold (and didn't infuse it) and it held a full vac for weeks and counting.

Hope this helps.

Fred