precaution when trimming your part ?

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precaution when trimming your part ?

Author	Message
Matthieu Libeert	Matthieu Libeert posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 955, Visits: 3.4K	I would go for the same theory as fred... I mostly wait 2 days before sanding epoxy... mostly I even postcure first and let the part cool down again for a few hours before sanding Matthieu Libeert Founder MAT2 Composites X Sports website: www.mat2composites.com
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Shaneer22	Shaneer22 posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 156, Visits: 14K	Did you use any spray adhesive,I have seen this on similar parts if so can be sanded and clear coated.
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Jess8bit	Jess8bit posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 133, Visits: 566	matthieutje65 (05/06/2013) I would go for the same theory as fred... I mostly wait 2 days before sanding epoxy... mostly I even postcure first and let the part cool down again for a few hours before sanding Ok, I will definitely wait longer before demolding and trimming. Maybe 20¨C is a too low temperature to work as fast as I'd like May I ask you how you post cure your infusion-made parts ?
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Jess8bit	Jess8bit posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 133, Visits: 566	Shaneer22 (05/06/2013) Did you use any spray adhesive,I have seen this on similar parts if so can be sanded and clear coated. yes, indeed, I use 3M super 77 spray adhesive to lay down the first carbon layer and the following clothes as well. I did not try to sand the part yet, only some polishing (which has had no effect). Thank you Shaneer
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Warren (Staff)	Warren (Staff) posted 12 Years Ago HOT Post Details
Group: Administrators Posts: 2.5K, Visits: 8.5K	Sounds like the sanding dust is showing up defects or your parts could do with a little longer to cure. You have to be really careful with temperatures and be 100% sure where you are working IS 20C for the time other wise the cure periods will not be accurate. Longer in the mould is better - well you cant do any harm that way. Post cure in the mould or elevated temperature cure to start with is the ideal situation. Warren Penalver Easy Composites / Carbon Mods - Technical Support Assistant
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Jess8bit	Jess8bit posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 133, Visits: 566	All right Warren, I'll pay attention to the temperature, and especially I will leave the part to cure longer
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Jess8bit	Jess8bit posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 133, Visits: 566	Ok so this time I've added sprayed GC50 gel coat, and waited for 2 days before demolding (no post cure though), and here's the result, once demolding : I'm happy coz' I don't have the surface problems I had before (even after trimming the part) So I'll wait for 48hrs before demoding, from now. Yet, if you look well, I have what looks like air bubbles stuck close to the cloth. Not many, but still. What could I do to really get rid of them ? During the infusion, I wait a "long" time before closing the vacuum line (to evacuate the air contaminated resin). By "long" I mean I wait until the resin reaches the catch pot and that some of it flow into. I clamp the vac line but I can still see some bubbles coming from the output of infusing part, inside the hose. Should I degas the resin before starting the infusion ? Also I suspect the Big vac pump draw the resin to fast ? Or is it irrelevant ?
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wozza	wozza posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 688, Visits: 5.4K	Do it the other way round. When the resin reaches the vac outlet and all the cloth is wet with resin clamp of the vac line but leave the resin feed line open for a decent length of time, a good 30 seconds or so depending on the size of the part. The resin will continue to be drawn in giving you a resin rich pin hole free part Carbon Copies Ltd
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Jess8bit	Jess8bit posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 133, Visits: 566	But why can't I find this by myself ?? Oh, I know, because YOU're the boss ! I'll try this for the next part.
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wozza	wozza posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 688, Visits: 5.4K	Ha Ha trust me I have learnt the hard way Carbon Copies Ltd
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