Pin holes in prepreg

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Pin holes in prepreg

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fgayford	fgayford posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 433, Visits: 1.2K	morepower (19/06/2013) carboncactus (19/06/2013) fgayford (19/06/2013) I used the easy preg. First the surface layer and then the backer layer with plastic sheet next . One layer of bleeder over the whole thing. (Just like you see Matt do in the demonstration exactly) I used full 29.9 HG vacuum ( bag clamped off and line cut after an hour drop test, this is the only debulking I do ) 212 fahrenheit temp (no ramping at all) 80 PSI pressure (in my autoclave) maintained for 6 hours. Fred Why did you use £100/sqm vacuum bag only fabric if you have an autoclave at hand? Exactly.... If you have an autoclave you can use £36/sqm material from SHD or PRF ect... I use there materials for back up with VTF which as £51 sqm inc vat is not cheap but still cheaper than £100 sqm easypreg. I dont have pin holes with VTF at all and using material from SHD for back up saves more money and is compatible with the VTF plus it gives perfect parts. I dont have an Autoclave to use so my parts are vacuum bag and oven only. I used this prepreg because I am still learning. I live in Canada so the shipment had to be worth it for my testing. I built my 65 gallon autoclave.(pictures are some where on this site) I tried just vacuum and oven and I know it works, but pin holes are my biggest enemy so I put the works in my autoclave just because I have one. There is a difference I noticed in the autclave stuff i have made. The compaction is incredible. If I tap the oven only part and then tap the autoclave part the autoclave part is a much higher tone, much more dense. On my next order I will try the cheaper stuff for sure. Fred
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morepower	morepower posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 242, Visits: 1.2K	OK..... I cannot talk about easypreg but I know with VTF I can get perfect parts without an autoclave and they are more than strong enough for what I want.... Here is the second part I ever made in pre-preg.. It is a fairing upper for my motorcycle.... It is almost perfect and the only issues are where my techniques are not correct... Here is the Monocoque seat and fuel tank... This is fully self supporting too.... No subframes just pure carbon. This was the 4th thing I had ever made.. Again no issues with pinholes... Here is a photo of one of the parts with a coat of lacquer on there... The red blotches are reflections of something in the workshop and it has not been flatted back or polished here either... This is straight out of the spray gun...lol
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carboncactus	carboncactus posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 243, Visits: 1K	I saw your DIY autoclave a while back. Its genius. I am keeping an eye out for a pressure pot on ebay, but nothing big enough for what I need. The one you have is ideal size.
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carboncactus	carboncactus posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 243, Visits: 1K	morepower (19/06/2013) I see a pinhole!
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Warren (Staff)	Warren (Staff) posted 12 Years Ago HOT Post Details
Group: Administrators Posts: 2.5K, Visits: 8.5K	carboncactus (19/06/2013) Why did you use £100/sqm vacuum bag only fabric if you have an autoclave at hand? Very good point!! Easy-Preg Surface Layer PrePreg Carbon is designed specifically for out of autoclave use so although it will work fine in an autoclave, is a bit of an expensive use of the material. Warren Penalver Easy Composites / Carbon Mods - Technical Support Assistant
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morepower	morepower posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 242, Visits: 1.2K	carboncactus (19/06/2013) morepower (19/06/2013) I see a pinhole! Haha... 1 pinhole... Not bad compared to all of the other materials I have tried... I know tomorrow you will not see it as Steve at Barwell bodyworks has worked his magic on the parts and they will be back with me tomorrow... He said it was the easiest work he had done even compared to some Autoclave stuff he had to paint... I LIKE VTF...lol..
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carboncactus	carboncactus posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 243, Visits: 1K	morepower (19/06/2013) carboncactus (19/06/2013) morepower (19/06/2013) I see a pinhole! Haha... 1 pinhole... Not bad compared to all of the other materials I have tried... Only messing lol. Ask this magician Steve what clear he uses. I do my own spraying and want to know what others use. Edited 12 Years Ago by carboncactus
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morepower	morepower posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 242, Visits: 1.2K	Only messing lol. Ask this magician Steve what clear he uses. I do my own spraying and want to know what others use. I know... LOL I will ask him...
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carboncactus	carboncactus posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 243, Visits: 1K	I have a mate that owns a body shop and he won CV body shop of the year award 2011, he uses Sikens. But I'd rather not, that stuff is £60 a litre!
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morepower	morepower posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 242, Visits: 1.2K	I can understand that.... lol.. Not cheap.. Here is steves site.... http://www.barwellbodyworks.com/
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