Bubbles visible in flow media

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Bubbles visible in flow media

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quinn	q quinn posted 7 Years Ago HOT Topic Details
q Group: Forum Members Posts: 155, Visits: 992	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.
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oekmont	oekmont posted 7 Years Ago HOT Post Details
Group: Forum Members Posts: 550, Visits: 27K	To determine the exact resin volume percentage, you have to measure the dimensions of the sample very accurate and calculate backwards starting with the density. Crp's density can vary between the density of the resin on the lower end, and the density of the fibre on the heavy end. as your panel is less dense than the commercial one, it has to have a higher resin contend. Different epoxys and carbon fibres don't vary that much in density. Higher resin contend isn't bad out of every perspective. The stiffness and strength against forces along the plane drop about linear with the fibre contend. But usually the critical property is the stiffness when bending the plate. And this drops far less than linear with the resin contend. But the resin contend lowers the density of the plate in a linear way. Because of that, to a certain degree, a more resin rich plate could have a slightly better stiffness to weight ratio when it comes to bending stiffness.
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quinn	q quinn posted 7 Years Ago HOT Post Details
q Group: Forum Members Posts: 155, Visits: 992	+x oekmont - 8/31/2018 1:18:33 AM To determine the exact resin volume percentage, you have to measure the dimensions of the sample very accurate and calculate backwards starting with the density. Crp's density can vary between the density of the resin on the lower end, and the density of the fibre on the heavy end. as your panel is less dense than the commercial one, it has to have a higher resin contend. Different epoxys and carbon fibres don't vary that much in density. Higher resin contend isn't bad out of every perspective. The stiffness and strength against forces along the plane drop about linear with the fibre contend. But usually the critical property is the stiffness when bending the plate. And this drops far less than linear with the resin contend. But the resin contend lowers the density of the plate in a linear way. Because of that, to a certain degree, a more resin rich plate could have a slightly better stiffness to weight ratio when it comes to bending stiffness. I haven't done an accurate test yet, but it does appear that my panel is less stiff than the commercial one, but maybe not more than 17% less stiff (weight difference) so like you said, it might still be possible that my panel is as or more efficient than the commercial one on stiffness to weight ratio, but I have a feeling the commercial plate is going to be a bit better. So I'm assumining the reason that I have higher resin content vs commercial panel must just be because they got better consolidation using prepreg and mechanical pressure. is there any way for me to improve resin/fiber ratio without using prepreg and pressing? Or am i probably getting about as good as i can with the current method without huge investment? I know there's potential for me to get a more efficient panel using light core material, but just curious if there's any way to improve my resin/fiber ratio. Not that I'm not happy with the results I got. The panel came out awesome and has a better surface finish than commercial, just not as strong. I guess i was hopeful that my most likely higher grade fabric could yield even better strength than the commercial plate, but obviously the process for which it's made is much more relevant. Edited 7 Years Ago by quinn
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