Prepeg over part core

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Prepeg over part core

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TomW059	TomW059 posted 7 Years Ago Topic Details
Group: Forum Members Posts: 6, Visits: 13	HI, I new to prepeg and want to try to make some parts without a mold, but instead use a 3D printed part core. I´m going to make a hydrofoil wing that is about 600mm x 150mm. The idea is to 3D print the core and then put on vari-preg 430 very carefully and trim to trailing edge of wing with precise overlapp, then a layer of easypreg with gloss layer out, and trim carefully. Then cover with release film- again with no wrinkles. Put it into V-bag and cure oven. I want to avoid any major grinding or sanding to avoid changing the wing profile- i would like to be able to only sand the trailing edge /fiber overlapp. and go directly to sand to 400-600-800g matt finish. Do you think this is possible ?
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Warren (Staff)	Warren (Staff) posted 7 Years Ago Post Details
Group: Administrators Posts: 2.5K, Visits: 7.9K	The concept may work, however \|I suspect the surface finish would not be perfect due to not enough even pressure being applied by the atmosphere. I suspect the part may come out with pinholes in it on the surface. The release film would have to be perfectly pread out without creases otherwise excess resin will flow into the creases compromising the surface finish. Warren Penalver Easy Composites / Carbon Mods - Technical Support Assistant
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TomW059	TomW059 posted 7 Years Ago Post Details
Group: Forum Members Posts: 6, Visits: 13	Thanks Warren, I'm not too concerned about pinholes, I'm prepared to do small fixes. In not looking for cosmetic perfection, but more interested in form perfection. The easy preg adds to my investment, is it helping me to achieve good form/surface? Or do you think I should skip it and use a surfacing/sanding coat ( epoxy with microballons) ?
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Fasta	Fasta posted 7 Years Ago HOT Post Details
Group: Forum Members Posts: 468, Visits: 3.5K	I have made a number of hydrofoils with a similar technique but I used a CNC solid fibreglass core (aka G10). You wont get any pinholes but the surface will need a little refinishing with a resin coat or two. The issues I would be concerned about are will the printed core stand up to the pre pre cure temp and hold it's shape? Also the pre preg will not likely bond very well to the plastic core so if you are expecting any significant structural strength from the core then it may not have that?? Fastacraft Facebook page
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