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quinn
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First infusion was a fail. 90% of the part saturated in the first 10 minutes, then the dry spots just stopped shrinking. Resin continued to flow for another 20 minutes but it just took the easier path and went to the catch pot. I guess it was a mistake to try and do it without infusion resin. Looks like my 600cps epoxy just wasnt quite thin enoigh. Just ordered some infusion resin to give it another try. Unfortunately I had to buy 90 bucks worth, 1.33 gallons. Only need about 70g per canopy plus extra but for some reason infusion resin isn't available in smaller quantities like a quart.
Is there any way to salvage my 90% infused part? Right now it's still bagged and curing. Once it's cured, can I just pull the bag and wet out the dry areas through the flow media and peel ply? Or is it not likely to soak in and reach the surface?
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Hanaldo
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You can't hand laminate it, but you can reinfuse the part if you can remove the consumables without demoulding the part. If you manage it then you just replace the consumables and redo the infusion over the dry areas. But if the part pops out while you're pulling off the consumables then it won't work, as you'll get resin bleeding onto the surface of your part.
Did you warm up your resin at all?
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oekmont
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Just puncture the bag on two opposite sides of the dry spot (near do the dry spot, but on the impregnated area. About an inch distance), and insert tubes just to the corner of the dry spot. Seal the tube/bag connection with tacky tape. Now run a second infusion, to catch up the dry area.
If you got a large dry patch, this means you got to much air in the system. Dry patches shrink until they reach atmospheric pressure, or the resin solidifies. Ideally they shrink to almost zero. If the area remains big, you might ask yourself where the air came from, to fill up big spaces under atmospheric pressure. There are two possibilities (If you bag itself is airtight)
-the pressure in the system not low enough when you starter the infusion
-your resin contained to much gas, which accumulated in one area wich was cut off from the vacuum line. Proper degassing would solve that, but I am talking against the wall with my opinion here at this forum.
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quinn
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Group: Forum Members
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+xYou can't hand laminate it, but you can reinfuse the part if you can remove the consumables without demoulding the part. If you manage it then you just replace the consumables and redo the infusion over the dry areas. But if the part pops out while you're pulling off the consumables then it won't work, as you'll get resin bleeding onto the surface of your part. Did you warm up your resin at all? Yep, I did warm the resin a bit, but couldn't too much. I first tested a small batch and if heating anything above just barely warm, it would continue heating itself to smoking hot and set up within 10 minutes. Warmed it just slightly and got about 35 minute pot life.
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quinn
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Group: Forum Members
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+xJust puncture the bag on two opposite sides of the dry spot (near do the dry spot, but on the impregnated area. About an inch distance), and insert tubes just to the corner of the dry spot. Seal the tube/bag connection with tacky tape. Now run a second infusion, to catch up the dry area. If you got a large dry patch, this means you got to much air in the system. Dry patches shrink until they reach atmospheric pressure, or the resin solidifies. Ideally they shrink to almost zero. If the area remains big, you might ask yourself where the air came from, to fill up big spaces under atmospheric pressure. There are two possibilities (If you bag itself is airtight) -the pressure in the system not low enough when you starter the infusion -your resin contained to much gas, which accumulated in one area wich was cut off from the vacuum line. Proper degassing would solve that, but I am talking against the wall with my opinion here at this forum. I started by doing a vacuum test on my layup, held full vacuum for a half hour before starting the infusion. Also I actually did fully degass the resin before infusion. Maybe not the safest way, did it in a jar, but removed all air. The one bit of air that was in the layup was the section of tube between the resin pot and the clamp on the resin line. Not sure how this is avoidable, but since that pocket of air pulls in before any resin, it should be evacuated, right? On all the videos I watch, i don't see anyone else do it differently, there's always that short section of tube with atmospheric pressure in it when starting. I guess I could ease up on the clamp a bit to allow the resin to rise to the clamp, then shut it again and let it pull vacuum again for a second, but haven't seen anyone else do that so I wouldn't think it would cause an issue.
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quinn
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Group: Forum Members
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Well, turns out I was mistaken. What looked like dry spots was actually just where I had peices of peel ply overlapping. So no dry spots. But here's the part that really pisses me off, I thought the part was ruined anyway so I pulled it after only 12 hours figuring I would just start again rather than trying to reinfuse, which means the resin was not fully hardened and I can now see a bit of print through. I'm assuming I wouldn't have had that if I left it bagged for another day to fully cure. Over all the part looks pretty good, not bad at all for my first infusion, next try should look better after a full cure
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Hanaldo
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You should definitely always leave it 24 hours, even with a total failure. Uncured resin can destroy a mould when you demould too early.
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quinn
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+xYou should definitely always leave it 24 hours, even with a total failure. Uncured resin can destroy a mould when you demould too early. I used pva so wasn't too worried about hurting the mold. Release was good, popped right out with very minimal effort, also it was medium speed hardener, says 8 to 10 hour cure. But yeah, quality of the part definitely would have been better with a full cure. Not too big of a deal I guess. About 15 bucks worth of material in each lay up and a couple hours work. Next one will be good. It was good practice I'll tell you what though, laying down weave into a mold like this with spray glue on top of pva takes SERIOUS skill. What a pain in the ass. I do plan to switch to a chemical release eventually but already had the pva and didn't want to spend more money for now. Also I figure after a couple runs with pva and the molds gets a bit seasoned, maybe I'll go for just wax. It's a risk I'm willing to take because I still have my plugs in perfect shape and making molds was only a days work. I can make another set if I stick a part going only wax
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quinn
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Group: Forum Members
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 After pulling the one side and seeing that I didn't actually have dry spots, I decided to leave the other half on while curing the rest. The pva also left a less than perfect finish but ill probably just clear coat until I either get some chemical release, or go just wax. Not terrible for a first try at infusion. Really curious to see how weight came out once I remove the peel ply and trim it.
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oekmont
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About the bit of air in the feed tube: open the clamp, until the resin reaches the clamp, then close it again, and wait a minute. After that open the clamp for the infusion.
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