Using Silicone Rubber for making vacuum bags

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Using Silicone Rubber for making vacuum bags

Using Silicone Rubber for making vacuum bags

Author	Message
Scout	Scout posted 9 Years Ago HOT Topic Details
Group: Forum Members Posts: 6, Visits: 19	Hi guys, Just wanted to ask if I can use Addition Cure or CS25 Condensation Cure Silicone Rubber to create a "Vaccum bag" over a mould? I was thinking if I could include the vaccum port/s into the mould flange itself and add a resin infusion port into this silicone rubber based vacuum bag would that work? Has anyone tried this? Sorry guys might be a stupid question... but I thought I would ask I am just a beginner but looking at the technical datasheet it looks like it can handle the pressure and the temperature?
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Hanaldo	Hanaldo posted 9 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	It would work for sure. If you use the addition cure silicone, then be aware that styrene inhibits it's cure. So if your mould is vinyl ester or polyester, then you will need a barrier between the mould surface and the silicone, otherwise you'll have a mess. PVA works. The other things you need to consider are part thickness, reinforcement fabric for the silicone, flow channels and sealing channels. Part thickness is as easy as using calibrated sheet wax to simulate the final part, or just layup an initial part using regular vacuum bag and then leave it in the mould when making the silicone bag. If you have a look on YouTube for Smooth-On's video about silicone vac bags then this will explain the reinforcement fabric and the flow and sealing channels. The sealing channels will be the trickiest part to make work.
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Scout	Scout posted 9 Years Ago HOT Post Details
Group: Forum Members Posts: 6, Visits: 19	Thanks for the advise Hanaldo. I have watched the videos. I will give it a go. As for the reinforcement fabric, can I use Infusion mesh as the reinforcement fabric?
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Hanaldo	Hanaldo posted 9 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	I suspect not, but it's a good question. I would use something like a fibreglass scrim tape I think.
	Reply Like 3
fgayford	fgayford posted 9 Years Ago HOT Post Details
Group: Forum Members Posts: 433, Visits: 1.2K	Scout (21/10/2016) Thanks for the advise Hanaldo. I have watched the videos. I will give it a go. As for the reinforcement fabric, can I use Infusion mesh as the reinforcement fabric? Hi Guys I too have been looking into reusable silicone vacuum bags. I have spent a great deal of time looking into it and have done some sucessful experiments with it. I used smooth on and it worked but there is a superior method offered by a company called Prairie Technology Group Inc www.SWORL.net I have found the company very approachable and helpful. They have a number of youtube videos up. Their sealing system is excellent compared to others also no fabric reinforcement is neccessary. Check it out. Fred
	Reply Like 2
Scout	Scout posted 9 Years Ago HOT Post Details
Group: Forum Members Posts: 6, Visits: 19	Thanks Fred. I will watch their videos Edited 9 Years Ago by Scout
	Reply Like 3
Hanaldo	Hanaldo posted 9 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	Jeez, can't say I'm impressed by their infusion video, they just absolutely flood the laminate and swish it around with their hands before shutting the feed valve and letting it pull the resin down through the rest of the laminate. Voids galore, not to mention uneven laminate thickness. Anyway, I'm sure thats just their infusion process. Their silicone bag looks good.
	Reply Like 2