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Bubbles visible in flow media
Bubbles visible in flow media
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quinn
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quinn
posted 7 Years Ago
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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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Bubbles visible in flow media
quinn
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7 Years Ago
the tree branching effect is classic of a tiny leak or some trapped air migrating. As it moves it changes direction randomly trying to take the path of least resistance. I would wait until you...
Warren (Staff)
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7 Years Ago
Panel came out great. Couple tiny pin holes but fine for my application. First time using frekote. Panel just about fell off the glass, worked great. Could also be a possible cause for the leak. I pu...
quinn
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7 Years Ago
So I weighed my plate, 0.26g per square cm at 2mm thick. it's 17% lighter than the commercial plate I have at same thickness. What does that indicate? I didn't think to weigh the dry lay up before...
quinn
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7 Years Ago
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...
oekmont
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7 Years Ago
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 stil...
quinn
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7 Years Ago
You can get a perfect resin ratio with infusion. This usually means, that you have to close the feed line before the resin front reaches the vacuum line. Ideally to the right time, that the excess...
oekmont
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7 Years Ago
Ah ok. This panel I just did, the resin was setting up right as it finished. Took about 40 minutes, probably because I'm still not using infusion resin, which i will next time. I did close the feed.....
quinn
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7 Years Ago
Yes, slightly. But but don't think that you might experience a difference. The biggest advantage of nonwoven cloths is a better pressure strength along the fibre. What makes a big difference is the.....
oekmont
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7 Years Ago
I need strength at 0/90 mostly, but I assumed there should be 0/90 non woven biaxial available right? If not, alternating layers of uni at 0 and 90 should be essentially the same right?
quinn
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7 Years Ago
Yes, biaxial fabrics are two layers of unidirectional fabric stitched together with the fibres aligned in the 0 and 90 axis. Fabrics with the fibres aligned at +45 and -45 are called double bias. The...
Hanaldo
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7 Years Ago
40 minutes is a very long time for such a "small" plate. Are you infusing along the shorter length? If so, your resin has to be medium viscosity. Like thin honey. A plate of that size would take me...
oekmont
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7 Years Ago
I infused the long direction. It was 250mm wide, 650mm long. I assumed my resin was too thick and infusion resin would help with that. It went pretty quick for the first half, like 5 or 10 minutes,.....
quinn
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7 Years Ago
Oh, if you meant 0/90 biaxial, then its basically the same as a regular cloth of the same weight. As far as my understanding goes, every cloth with 2 fibre directions is called biaxial. Most of them....
oekmont
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7 Years Ago
Yeh that really makes more sense to me - it doesnt matter what axis the fibres are on, if it has the fibres going in two directions then its biaxial. Guess it's just a regional thing. Definitely her...
Hanaldo
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7 Years Ago
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.
oekmont
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7 Years Ago
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