I was looking for a step by step write up, as far as how to prep the mold, lay the fabric and other supplies, and lay the hose/bag down. Would it be more appropriate to post this in a new thread? i also am having a hard time choosing epoxies and figuring out what kind of pot life my epoxy needs to have. I have bought some green flow media, 200.0015 stretchlon Airtech Airtak2 spray adhesive, and AdTech Epoxy. Im going to get a little time off work soon and was hoping to do a little playing around with these materials.
Don’t use the Stretchlon!!! Never use stretchable films for infusion. Use a multilayer bagging film. The other materials should work, wich type of the resin?
I find Stretchlon materials, while nice in idea , that they stretch, they constantly get pinholes from the infusion mesh and create more issues than they solve.
Dang! I already ordered some! Ok so normally I use medium (2mil) duty plastic sheeting bought from Home Depot. I’ve never found any pin holes in it. Can I just use this stuff? What exactly is “multi layered” and where can I buy some?
And don’t use the PE stuff from a home depot. All PE films are microporous. A multilayer film is a PA/PE/PA compound bagging film. They are not stretchable so you have to make wrinkles, but they are tight.
It is also a problem if you stretch you bag. A stretched bag always wants to become flat again, so it will suck resin. You will have a lot resin where it is stretched and/or voids.
DD, I know you have said you don’t have any distributors in Australia at the moment, but do you know if any of your other distributors will ship here? I’d love to give MTI a go.
We have a distributor in Australia. Just take a look at our homepage at distributors.
Penetrator Fins is our distributor in Australia.
Marvelous! I hadn’t checked your website, which was foolish of me 
Thanks mate.
Hello Hanaldo, happy to share info with you re: suppliers etc. what are you making over there?.
Regards
John Hayes
www.bladerunneroutriggers.com
I will definitely not use it. Still looking for a source to get multilayered film from here in the U.S. any ideas? I’ve only got a few weeks off from work and would like to order the right materials ASAP.
What you can do with the Stretchlon is double bagging. But even if it is a stretchable material make lots of pleats to avoid stretching.
Hi John,
I would appreciate that mate, thanks!
I mainly make composite auto parts, usually carbon fibre. I specialise in custom intake piping, but do pretty much everything. I also make various parts for a Stemme S10 motor-glider, and carbon fibre trays for a local geologist/artist. So a bit of a mixed bag.
Hey guys,
I decided to give MTI hose a shot because I’m still have pinhole problems with my surface finish. I ended up using a length but I still got some pinhole artifacts (in fact, more than I’ve gotten without the system) so I’m very confused. I’d just like some input on what I’m doing wrong since I know the product works well from other people experience.
I followed all the basic points. Very nicely degassed resin and a leak free bag that went through a full drop test. The part is about one square foot in size, and I used an 8 inch length of MTI hose on just one side of the rectangular part. Didn’t notice any air bubbles racing through, and the hose was properly sealed after the infusion completed.
I’ve attached a picture of the results. The pinholes are so large I’m not even sure if they qualify as pinholes anymore, they might’ve graduated to full blown voids. The part was full infused with every inch wetted out, and I used a thin-enough infusion resin (~200cps) but still ran into these errors. Any help would be appreciated!
What was the vacuum level you reached?
on an analog gauge, it read 28-28.5 inches. I’m in Dallas, TX so we’re 450 feet AMSL if that helps. I’m using a new robinair pump with properly sealed fittings so I’m guessing that my vacuum is strong enough.
A analog gauge is not helpfull, but it is a oil lubricated rotary pump or? So it should be able to get the vacuum you need. What resin do you use? What flow media?
Yes, it’s an a two stage rotary vane pump. Robinaire 15xxx series (forget which exact one but the 5cfm model) that’s very common around here. I’m using the Proset Infusion line and Greenflow 75 infusion mesh. I’m going to demold another part today, hopefully it was just a fluke.
How do you guys normally degas? I let it degas until I can’t see any more bubbles while it’s under vacuum, and then remove it after that. I don’t bleed air into it and then pull vacuum again, which I’ve seen someone mention before. I’ve tried it once and it doesn’t seem to have any effect, but that’s the only thing I can think of atm that I’m doing differently.
I have worked with that stuff several times in the States, should work. Did you clamp the feed line too early? Place the resin pot about 3 ft below the part and wait until the resin reached the MTI hose, than clamp the feed line.
I clamped it after it reached the hose, and in fact I let it saturate the lower portion of the hose so the feed line was open for quite some time. I did this because I noticed the white membrane itself will suck up some more resin over time, once the feed line is clamped. I didn’t want that process creating any voids in the immediate area next to the hose.
Here’s an idea… could I have used too small a length of hose, and had the resin flood the part too quickly? I only used a ~15cm length hose for a 30x20cm part that is about 1200gsm thick. Maybe the resin fed in more quickly than the MTI hose could evacuate trapped air. The part I made today has a ~30cm length of hose…hopefully this test will tell us more.
What purpose does leaving the resin feed pot 3ft lower serve? Doesn’t that just prevent against resin pooling at the input?
on such a small part you will evacuate fast enough, even with a small piece of MTI. Tha memnrane does not really suck resin, just the pores in the membrane a filled so that it becomes light blue.
I never had problems infusing too fast, but try to slow the infusion down a little bit. Have you made a brake zone, let the flow media end about 1" before the layup ends?