First Infusion - Success, Failure & Lessons Learned

First ever infusion yesterday!
Overall, I think it was a success despite a failed part. The goal of this first test was to get a feel for working with all these components and get an accurate thickness plate for compressed 18oz fabric.

I cut a 75x10mm piece of 18oz 0/90 and then added an additional 18 layers of fabric on top of it in a stair-stepped fashion. Over that went the Peel-Ply and then the Perforated film. After that, the Resin Distribution Media and finally the Vacuum bag. The work was laid up on a piece of waxed glass.

Fabric Cut and laid up

Perforated Film over Peel Ply

Vacuum pulled

Drop Test

I pulled the vacuum down to 50mbar to do the drop test. I was losing vacuum pretty quickly and quickly found the problem to be the tapped barb fittings located on the PVC vacuum canister I built earlier. A seal of tacky tape around the base of the fittings solved that problem and that was it for the leaks found. So far, so good!

After this, I pulled the Vacuum down to 15mbar for the infusion and proceeded to open up the Resin supply. I was surprised at the speed of the resin front through the part and failed to slow it down adequately, so I'll have to work on a better solution for that.

Total Infusion time was about 3.5minutes.

It looked perfect from the top and I was as happy as could be!
However, the next day I flipped the part and saw the failure:

Large un-infused area

Un-Infused area

I sat around for a while looking at the part, feeling pretty down about the whole thing when I saw my error. As it turns out, I had installed the Resin Distribution Media past the side edges of the part. I believe what happened is the resin infused through the fabric until the thickness became so great that it simply became easier to flow through the Distribution Media on the sides of the part rather than pushing through 19 layers of glass. If I had seen this, it is possible the problem might have resolved itself by letting the resin continue to run instead of cutting it off when it hit the resin break.? Also, if you look closely there are several resin starved areas throughout the part. I believe this is due to the resin speed being too fast.

I have another few tests planned, but I need to get some decent scissors before trying again!

As for all the materials and equipment used, I think they performed flawlessly - from the pump to the leak detection to the tacky tape, fabrics, resin & vacuum bag. This failure was purely operator error and inexperience.

I did get the thickness measurements I was after and now I have a cool memento to hang on the wall!

We'll see how it goes next time...