infusing thin sheet foam sandwich ?

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infusing thin sheet foam sandwich ?

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Hanaldo	Hanaldo posted 9 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	I just punch holes with a small flat head screw driver, so probably 2mm dia. Print through is a problem though, I do get print from the holes. It's just the shrinkage of the excess resin, so anywhere you have a build up of resin compared to its surroundings you will see it, doesn't matter how big it is. Post-curing is the best solution. Edited 9 Years Ago by Hanaldo
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MarkMK	MarkMK posted 9 Years Ago HOT Post Details
Group: Forum Members Posts: 338, Visits: 2K	Just to revive this thread a little, I recently made a couple of 0.5m square foam sandwich panels, using EC's 3mm material. I usually do these in two steps - infusing two plys of carbon/e-glass then, when cured, the foam is bonded to the reverse with and an additional two layers wet-laid on top. The stack is then vac-bagged to draw off some of the excess resin. Results are usually great However, I wanted to try and speed up production, so I first tried scoring and drilling the foam, then just driling it at approx. 50mm centres to see if it would work okay as a one-shot infusion. I figured that the additional time spent prepping the foam would, potentially, save a fair bit of additional time Surface finish and bond was great on both, however, the grooves in the foam on the first panel and the holes drilled on the second were evident on the surface in a kind of hologram effect. It looks like the fabric had been ever so slightly pulled up into these recesses under vacuum and the minor uneveness was evident when reacting with the light The grooved panel had a kind of tartan visual effect to it which, although not altogether unnatractive, was not the desired outcome! The drilled-only panel showed dark spots where the holes in the foam were Clearly just drilling was good enough to infuse, but would I need to add surface layers to avoid the holes being visible or can I get away with even smaller holes? The ones drilled were approx 3mm diameter, so I wonder if reducing the size might help avoid the visual print through? How big are your holes?? :-) Edited 9 Years Ago by MarkMK
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Fasta	Fasta posted 9 Years Ago HOT Post Details
Group: Forum Members Posts: 468, Visits: 3.5K	Finally did some more infused samples the other day and these worked out great. Gel coat 2 x 180g glass cloth 6mm 100kg PVC foam with 2mm holes on 20mm centres 2 x 180 glass cloth polyester infusion resin. Fastacraft Facebook page Edited 9 Years Ago by Fasta
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Hanaldo	Hanaldo posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	Will work fine mate. You don't even need to score it deeply, just light scoring works fine and saves on resin/weight. I've infused 5 and 10mm thick Divinycell in this manner, holes drilled at 2" intervals and connected on one side by grooves made with a metal ruler. Infuses like normal if you've got flow media across the entire laminate. Largest I have done is 2.5sqm, but it doesn't infuse slower than a regular laminate so I don't think you will have too much issue if you've got the pot life.
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ChrisR	ChrisR posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 363, Visits: 3K	Don't know, the largest I've infused is 1500x500
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Fasta	Fasta posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 468, Visits: 3.5K	ChrisR (21/05/2015) The foam I use is just drilled at about 50mm c/c each way (6mm core), I only have a couple of layers each side and not had an issue I could test this out. I am still concerned about the overall speed. Is it fast enough to get an area done. I am doing 3.2m2 Fastacraft Facebook page
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ChrisR	ChrisR posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 363, Visits: 3K	The foam I use is just drilled at about 50mm c/c each way (6mm core), I only have a couple of layers each side and not had an issue
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Fasta	Fasta posted 10 Years Ago HOT Topic Details
Group: Forum Members Posts: 468, Visits: 3.5K	I am wanting to infuse a 5mm thick PVC foam sandwich and I am asking myself if having the foam grooved on one side only but also with drilled holes will work ok. Foam down with the grooves against the mould/outer laminate and then a full surface flow medium on the inner skin side which has no grooves, flow medium outside the peel ply. I hope this makes sense. ?? Anybody else infusing thin foam cores? Fastacraft Facebook page
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