removing pin holes

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removing pin holes

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TomDesign	TomDesign posted 9 Years Ago HOT Post Details
Group: Forum Members Posts: 454, Visits: 2.5K	any advise guys to me that want to build autoclave and to start using pre pregs as i think infusion is real pain?
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Hanaldo	Hanaldo posted 9 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	Well my advice would be to really think about whether you need an autoclave or not... I think they are fairly redundant these days. Obviously still have their place in F1 and aerospace, but for anything else OOA pre-preg will do a great job. Infusion is definitely a pain compared to pre-preg. If I could do everything in pre-preg I certainly would!
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TomDesign	TomDesign posted 9 Years Ago HOT Post Details
Group: Forum Members Posts: 454, Visits: 2.5K	so Hanaldo like wings door panels or mirrors best pre pregs as infusion i think real pain with temperatures and etc? autoclave i guess simple owen and from outside vacuuming pump? correct?
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Hanaldo	Hanaldo posted 9 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	I only really do smallish things. Anything bigger than say 0.5sqm I will usually infuse, just due to the cost of prepreg. Unless it is a super complex part in which case pre-preg is quicker, easier and has less risk of failure. And no, an autoclave is a pressurised oven made for regular pre-pregs so you can apply pressures of 80-150+ psi. You want out-of-autoclave pre-preg (what Easy Composites sell); this just cures under vacuum pressure and so only requires an oven with an active vacuum source.
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morepower	morepower posted 9 Years Ago HOT Post Details
Group: Forum Members Posts: 242, Visits: 1.2K	With out of autoclave pre-pregs getting better there is less need for an autoclave for almost all the work we as either small businesses or hobbyists do. The added strength given is not that great so adding one more layer or not making a part that is quite so structural is the compromise. How many meters of material would we need to use to make the cost of the autoclave worth while? The one thing that does seem important is the ramp and dwell controller for OOA's. I know some get great results without one but having one does take out human error where the oven is concerned. Plus the cost of a controller is only a small one which could be paid for with one or two items that fail due to user error.
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TomDesign	TomDesign posted 9 Years Ago HOT Post Details
Group: Forum Members Posts: 454, Visits: 2.5K	so guys i simply need to make big owen correct? any help what is needed?
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morepower	morepower posted 9 Years Ago HOT Post Details
Group: Forum Members Posts: 242, Visits: 1.2K	TomDesign (05/12/2016) so guys i simply need to make big owen correct? any help what is needed? Yes.. You can make it as simple or as complex as you want.. The better is it insulted the less power it needs is obvious. But there are a few things you need to do and not cut corners. You need a duct with a fan that is driven independently of the heater element. You can still run a cheap heater but you need to rewire it to let the fan run from its own power cable. Also use a fan that can take higher temperatures as most chinese heaters have a thermal cut out on the fan motor that will not let you run at the temperatures you want.. http://www.ebay.co.uk/itm/High-Temperature-Extractor-Fan-VA-16-2-/221929876966?hash=item33ac0d2de6:g:WOEAAOSwj0NUfHGa The duct needs to force air to flow through the whole oven. So I have it pulling air from the front of the oven across the door. It is ducted to the back corner and blows up to the roof of the oven so the air has to go corner to corner.. The box can be MDF and expanded foam insulated (kingspan) if you want and just use a sliding door of MDF. It will lose some heat if you do this (I have but I have a lot of old sheets and blankets draped over the door to keep the heat in as much as possible). Then you need to have a controller as it makes your cure repeatable with every cure cycle.. you can get ramp and dwell controllers from eBay if you want to just get going. They are called re-work station controllers and do need some thought as the timers work in seconds not minutes or hours. Plus you need to add a on off switch to the control panel or the controller will not work, I think the Omega ones do this too, but their instructions are better than the ALTEC PC410 instructions. Wire the controller to a relay (mine is 40amp) to turn the heater element on and off. http://www.ebay.co.uk/itm/Altec-Pc410-Temperature-Controller-Panel-For-Bga-Rework-Station-Rs232-Module-O-/122009754612?hash=item1c68591bf4:g:dmsAAOSwImRYIlZw After that all you need is to plumb in some vacuum pipes....
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