I had a quick question on resin breaks. This is my second infusion and I am adding a small resin break at the vacuum line because in the first attempt the resin reached the vacuum line very quickly and didn't have time to fully degas. I ended up with a lot of trapped air bubbles in the finished part and this was after drawing a decent amount of aerated resin down the vacuum line. Question is do I

a) Clamp the resin feed line off as soon as the resin reaches the break (and the part is fully wet through) and then allow the resin to cross the resin break and reach the vacuum line (drawing any out if necessary) before clamping off the vacuum line.

b) Clamp the feed line after the resin crosses the resin break and reaches the vacuum line.

I am inclined to think a) as this will stop any more aerated resin being drawn into the part and fully degas the infused resin. I assume there is enough resin in the infusion that it is not going to desaturate the main part die to the small area of resin break. Only thing I was thinking with b) was whether this might let a bit more resin into the part and reduce the likelihood of pinholes.

Any thoughts?

There is no one correct answer. It depends on how big your break is, what your layup is like, etc. You get a feel for it after a few infusions.

You can also slow down the resin feed by partially clamping it thus allowing the resin more time to soak in as it flows across.  Just bear in mind the resin pot life if you do this. 

Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant