Infusion bagging material

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#1

So I’ve tried searching this and have found some interesting stuff but my question is what do you guys use for vacuum bagging material when doing infusions?

I recently infused a 14.5’ kayak and used some very stretchy 2 mil material from a local composites store. I don’t know what brand it is but I had leaks everywhere.

The worst part was that most of the leaks started showing up after the infusion had started which is very frustrating. Is there any reason I couldn’t use a heavier plastic film like a painters drop cloth from the hardware store? It wouldn’t stretch but if there’s enough pleats in it that shouldn’t matter, right?

Any tips would be welcome.

#2

I have had different luck with different bagging materials…some were more prone to “spider cracking” than others. I don’t see why the heavy duty painters drop film wouldn’t work, something around 4mil’s or more should be OK.

However for something as large as 14.5’ I would not suggest cutting corners on the bagging material. Your material costs on something that large are probably fairly substantial between resin and fabric. I’d say just get a better bagging film meant for infusion (I like the Wrightlon stuff). It would suck to ruin two infusions and waste all that material

#3

Never use stretchable film for infusion! Use a multilayer film with 70-100 microns and make lots of pleats.

#4

I agree that cutting corners is the last thing I want to do on this. I was able to salvage the parts but it took many hours of rework to get them to look good.

DDCompound, you say never use stretchable film for infusion and I’ve heard that before. Do you have any specific material recommendations and what exactly do you mean by multi-layer film?

#5

I order my tube bags from acp composites but up in mn express composites carries what you probably need. Any film by air tech I think should be good that’s at least .002 thickness.

#6

Thanks Infused. I work a few minutes away from express composites and actually bought all this stuff there. Looking it up it seems that the film I bought is made by Northern Composites and is part number LTF-250

http://www.northerncomposites.com/partners/northern/bagging-films/ltf-250

I’m using Adtech 820 epoxy, I haven’t mentioned that yet.

#7

Hmm. Now that I’ve found the maker of this film I pulled up the TDS and found this statement:

LTF-250 is engineered for use with most standard 250°F curing epoxy resin systems. It is highly recommended to isolate the resin from the bag as it is common for resins to attack the bagging film which can result in bag failure.

Might this explain why i have all these leaks showing up 15 minutes into my infusion?

#8

Definitely doesn’t sound like a suitable material for infusion.

#9

I like Adtech 820 epoxy but not for infusion. It’s to high viscosity for infusion. Look for an epoxy with around 150 to 300 centipoise (sp?) and you will get much better results. I also agree with previous comments about bagging material. I like Huntsman infusion epoxies.

#10

Search for Big Blue, it’s awesome.

#11

I think I am going to give the Pro-Set 114 infusion epoxy a try real soon. https://www.acpsales.com/OnlineStore.php?cat=5534

#12

Adtech 820 with a medium hardener has a viscosity of 350 cps which isn’t far from what you recommend. It infused just fine, my issue came in when holes started showing up in the vacuum bag. That’s going to be bad no matter what you’re infusing with.

#13

Some show and tell of what I was working on…