Envelope vacuum bagging question

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Envelope vacuum bagging question

Author	Message
Massimiliano	M Massimiliano posted 4 Years Ago HOT Topic Details
M Group: Forum Members Posts: 167, Visits: 1.1K	Hi, for the mold I have it would be easier to use an envelope bag instead of a bag attached to the flange. But how do you prevent resin running over the flange and filling the back breather cloth?
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Hanaldo	Hanaldo posted 4 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	You can't. One of the drawbacks of envelope bagging.
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Massimiliano	M Massimiliano posted 4 Years Ago HOT Post Details
M Group: Forum Members Posts: 167, Visits: 1.1K	+x Hanaldo - 10/15/2020 5:22:49 AM You can't. One of the drawbacks of envelope bagging. So you apply release film on the back to avoid the breather become solid with the mold?
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Hanaldo	Hanaldo posted 4 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	If you intend to use the mould more than once then yes, this is generally best. Or skip the breather and just do several layers of peel ply. It is messy and can make using the mould a royal pain in the ass, hence why it generally isn't the chosen method for infusion. I will often spray tack a layer of vacuum bagging film to the back of the mould, then do a layer of release film, then the breather. This sort of makes the release film/breather layers disposable, while the vacuum bagging layer stays on. If you don't do the layer of bagging film, I've found resin does quite often find it's way underneath the release film and can mechanically lock things in place.
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Massimiliano	M Massimiliano posted 4 Years Ago HOT Post Details
M Group: Forum Members Posts: 167, Visits: 1.1K	+x Hanaldo - 10/15/2020 7:02:33 AM If you intend to use the mould more than once then yes, this is generally best. Or skip the breather and just do several layers of peel ply. It is messy and can make using the mould a royal pain in the ass, hence why it generally isn't the chosen method for infusion. I will often spray tack a layer of vacuum bagging film to the back of the mould, then do a layer of release film, then the breather. This sort of makes the release film/breather layers disposable, while the vacuum bagging layer stays on. If you don't do the layer of bagging film, I've found resin does quite often find it's way underneath the release film and can mechanically lock things in place. Thank you!
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Warren (Staff)	Warren (Staff) posted 4 Years Ago HOT Post Details
Group: Administrators Posts: 2.5K, Visits: 7.9K	On moulds where I have needed to envelope bag regularly, I sanded the back of the mould smooth, then brushed on a thin layer of resin. Once cured I would Easy Lease coat it. That way any resin on the back easily came off leaving the mould relatively clean. Warren Penalver Easy Composites / Carbon Mods - Technical Support Assistant
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Massimiliano	M Massimiliano posted 4 Years Ago HOT Post Details
M Group: Forum Members Posts: 167, Visits: 1.1K	+x Warren (Staff) - 10/19/2020 4:26:18 PM On moulds where I have needed to envelope bag regularly, I sanded the back of the mould smooth, then brushed on a thin layer of resin. Once cured I would Easy Lease coat it. That way any resin on the back easily came off leaving the mould relatively clean. Brilliant, thank you!
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