By Finnluxury - 11/16/2018 2:19:58 PM
Hi,
It's long time since I have wrote anything and I wanted to share some of my experiences now.
As many of U may know, I have been working with carbon fiber and fiberglass parts for a long time. Mostly every composite part that I have been making, is made by resin infusion. Problem with resin infusion have been always the fact that sealing the vacuum bag takes a lot of time and it is very easy leave it to have a leak. As I have wrote in some older thread, the micron meter helped a lot to get reliable sealing. Basic vacuum gauges are not enough to determine 100% reliable that is the bag leaking or not(unless u wait long time and check vacuum drop). Since we need to make so many parts and we need a fast cycle for the parts we have been going more and more to reusable silicon bags. Basically we no longer make basic resin infusion with nylon bags. There is several reasons for it:
-Silicon bag is reusable (some companies have used it for cycle of 3000)
- No Waste
- 100% reliable sealing (never vacuum leaks)
- Can hold vacuum for days without running vacuum pump
- Seals in matter of seconds
- Made in the shape of the mould, so there will be no corners that the bag wont be reaching.
- Environmentally friendly.
Of course it's a investment to make the silicon vacuum bag, so its not good for one off items, but if u make more than 2 parts, it will definitely be worth of making it. Negative thing of the bag is that it wont be lasting for long with epoxy parts. Lifetime will be 25-100 cycles. I made a 1,3 meter long miniature boat hull mould with silicon bag for demo purpose and it took just minutes to infuse the part. After I have add the fiberglass, I just add the silicon bag over it and I will get perfect vacuum in matter of seconds and its ready for infuse. I never had any leaking issues with the silicone bag. Also with a Morph runner I can make a channel for resin flow, that after infusion I am able to get it disappear. No traces of flow channel, so no need for removing hardened resin, like normal channels would leave.
I am not promoting anything or selling anything with this text. I just want to give u all my honest opinion of silicon vacuum bags. Highly recommend for testing it. 
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By scottracing - 12/9/2018 6:34:41 PM
yes this process is aimed at multi part production, we had a very good turnout at the Alan Harper Training / Demo last week at the NCC.
I will certainly be using it on some of my infusion tooling and possibly my semi production prepreg tools too.
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