Talk Composites - The Forum for Advanced Composites

Bubbles visible in flow media

http://www.talkcomposites.com/Topic29169.aspx

By quinn - 8/30/2018 1:58:12 PM

Here's a panel I infused 30 hours ago. As you can see in the pics, I have some bubbles in the flow media. Before infusing, I pulled full vacuum and left it for 20 minutes, no vacuum loss. Fully degassed my resin in vacuum before infusion. During the infusion I could see some very tiny bubbles flowing with the resin. Finished the infusion, next morning I could see all these bubbles. Looking through the glass on the finished side, it looks flawless. No voids or bubbles. Probably going to debag it in a couple hours and see how the panel looks. Hopefully bubbles are only in the flow media.
So what went wrong? Is it likely I developed a leak somewhere during the infusion? Or I didn't have full vacuum in the first place? My gauge only pulls to 26 but i can boil water with vacuum so it's at least hitting over 29. If I was only getting 29.5 inches or so, would that be bad enough to end up with air like this? Or more likely that it just started leaking at some point? After 30 hours, the bag is still pulled down very tight.  I'm also still using regular laminating resin, 600cps, not actual infusion resin. 
By oekmont - 9/2/2018 4:28:44 PM

1/4" should be enough. But you should always try to infuse the shortest possible distance. This makes life much easier. And you could have used the gained 30min for something else.