problems in (to tight?) corners?

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problems in (to tight?) corners?

Author	Message
dubster	dubster posted 8 Years Ago HOT Topic Details
Group: Forum Members Posts: 15, Visits: 126	helloEveryone. I havea problem with my last project. I just cant get a decent finish on thislittle part. Al the straight areas are fine, just can't get these cornersright. I tried a few other setups but this one last night was even the worse imade !! usethese parts: -2layers of carbon fibre -alstuff that can be sold in this kit on easy comp webshop as consumables. https://www.easycomposites.co.uk/vacuum-bagging-starter-kit so peelply / perforated film / breatherlayer / bagging film is all easy comp. The laminating resin EP-L2-F-5 is usedfrom Easy comp also. Itlooks that the bag closes in this setup complete everytime, but like the picturesshow, i have places where the is no epoxy at al. I madechanges to the setup like: extra breather layer as I suspected this could helpme close the gap between carbon and corners. I’m sure that there is enough epoxy as the breather has thebreather has excess resin when finished. I wasthinking 2 extra layers of carbon could help me also but I first want to hearover here if there aren’t any other things I’m completely missing?
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scottracing	scottracing posted 8 Years Ago HOT Post Details
Group: Forum Members Posts: 460, Visits: 5.2K	This is all down to bridging of the material, you need to ensure whilst you layup and especially when you pull vacuum on the part that the material is pushed into the corners, extra material and breather will not help you. Also make sure you cut the peel ply into strips in the tight rads as it will bridge causing the laminate to pull out of the corner.
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Rich (Staff)	Rich (Staff) posted 8 Years Ago HOT Post Details
Group: Administrators Posts: 167, Visits: 4.6K	I agree with scottracing, improving your bagging technique and ensuring that the material is pressed into the corners with no gaps between the composite and the tool or the vac bagging consumables and the back of the reinforcement will definitely improve the end results. You could, if needed use a very light application of spray tack in the problem areas to help you to sit the carbon against the tool face and temporarily secure it whilst applying the resin. In addition, what vacuum level are you running to?
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dubster	dubster posted 8 Years Ago HOT Post Details
Group: Forum Members Posts: 15, Visits: 126	ok, will take care of this thanks for the info !!
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Warren (Staff)	Warren (Staff) posted 8 Years Ago HOT Post Details
Group: Administrators Posts: 2.5K, Visits: 8.5K	Id agree with bridging being a factor here. For vacuum bagging you want to ensure you are not using too high a level of vacuum as you may find you squeeze out too much resin. Typically you could be between 10-30% vacuum depending on the part. Warren Penalver Easy Composites / Carbon Mods - Technical Support Assistant
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polaraligned	polaraligned posted 8 Years Ago HOT Post Details
Group: Forum Members Posts: 13, Visits: 284	Warren (Staff) (23/02/2017) For vacuum bagging you want to ensure you are not using too high a level of vacuum as you may find you squeeze out too much resin. Typically you could be between 10-30% vacuum depending on the part. Does this apply only to hand laid up parts? Infusion always uses full vacuum, right?
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Rich (Staff)	Rich (Staff) posted 8 Years Ago HOT Post Details
Group: Administrators Posts: 167, Visits: 4.6K	Absolutely, for Infusion or PrePreg production, you always need to be running at full vacuum. For vacuum assisted wet lay, we find the best results are at lower vacuum levels as suggested above by Warren; the reason for this is that with too much resin, you ultimately draw more resin out of the part, through the release film and into the breather leaving you with low resin content and pin-holing or dry patches on the moulded face.
	Reply Like 3