Opinions and uses of "Airtac 2" or any dry fiber adhesive for infusion

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#21

HeyBen, Herman, Wyowind…

THANK YOU!!!

So the sample cured and I was sort of scared to see what was going to happen during the release portion of the test.

Honestly, I have never had a part release so easily throughout my entire composite career! No wedges were needed, not even really any effort was applied… just took a corner with my finger and the entire piece just slid right out! Frekote Semi-Permanent 770 release is the best thing to happen in my composite business since carbon fiber itself. I absolutely can not put to words the amount of excitement and amazement I am in right now!

And the original issue of repositioning the carbon after I had already stuck it down with Airtac2… SOLVED!!! A word of advise to myself 6 years ago… “ditch the PVA man, go for semi-permanant!”

There was a sample that I sprayed with Airtac2 and pressed tightly into a hard corner of the mold, then pulled it off and repositioned it. It released absolutely perfectly, no drama… it was as if I had never repositioned it!

I seriously can not believe how fantastic this stuff works… its crazy!

-C

#22

Good to hear! I switched about 7 years ago and would never go back. I would recommend using the sealer in the future though. :slight_smile:

#23

2 days ago I did a test infusion on a piece of glass, and I tried the Airtac 2 adhesive to see if it left any imperfections on the surface.

I sprayed a square of airtac2 (lightly) on the mould surface (treated with a release by Chemtrend), waited for a couple of minutes (basicly too long) and the spray still had great holding power. I then infused with epoxy resin. (Huntsman).

After cure and release, the spot where the Airtac was, could not be traced, according to my lab technician. (I live some 250 km / 150 miles away from the lab, I am not there often). But I believe him.

No pinholes either. Thanks DD Compound, for the MTI hose.

#24

Herman,

I most commonly have similar results with Airtac2. As long as it is lightly misted on I have found that it holds the fabric in place REALLY well, and through the infusion it’s as if the adhesive is desolved and removed from the laminate on the front line of the resin, leaving a flawless laminate to cure.

My biggest issue was that it would pull the PVA off the mold face so that the part release was extremely “sketchy”. This new Frekote semi-perm release is undoubtedly the one component I’ve been missing for years… even a day later after I released the test panel I am still amazed at how well it worked! I can’t stop talking about it in the shop, haha!

-C

#25

I’ve used 3m77 a few times and always had some pin holes on the mold surface, from what I beleive is a reaction with epoxy resin, softening the 3m77.

I searched for a purpose formulated tack spray for epoxy and found nida tack and NuTack® E 046-4103.

Anyone have experience with either one of these sprays?

#26

No experience here, I am sorry.

PVA usually is a big mess. It has its merits, but not as a general mold release.

Useful for:

-the first 2 parts out of a polyester mould
-really crappy moulds
-delicate masters owned by your pickyest clients, with unknown paint on them.
-Gibco Flexmold or any other surface that does not withstand styrene attack (if using polyester)

#27

If I’m using an in mold clear or pigmented gel coat and am infusing over the top. Super77 by 3M has always done me right. The only times I’ve ever had problems were a few years ago when I’d spray on way too much.

Now I’ll spray a light to light/medium coat. Just enough so itl stick to the molds, but not to my fingers.

#28

Can I use freekote seal and release with epoxy molds?

#29

In general, yes. But TEST TEST TEST

Also, epoxy molds tend to be reactive on the surface. Doing the first 2 releases with PVA seems to help getting rid of that surface reactivity.

#30

Freekote works great, no worries with airtac… done loads of these sorts of parts. Apply several coats of freekote and your release is good. You can probably do 2-3 parts without re-releasing but, i tend to add one coat between parts. Hence it’s semi-permanence. Using spray tack on free kote doesnt effect release. I think airtac kinda sucks personally. I have had issues of it leaving residue in parts. I was using vinylester at the time, and maybe that was part of the issue?

I started using another brand called infuzene and it was much nicer, stronger, and easier to manipulate; the can says its for infusion specifically. I found that you can’t get it in california now so I bought some stuff called star stuck and it is similar but not the same.

Also freekote comes in pre soaked wiping cloths. We just got 4 cases in and are not buying the gallon cans anymore. The wipes are supposed to have like a tenth of the vocs… or some huge reduction. I’ll write up a little blurb after I try em.

Simoncbrr1: yes you can seal and release with freekote products. As herman says, testing is good. But I’ve used freekote sealer and release on epoxy molds and prefer it over wax, much safer and easier releasing.

#31

does Kreekote works with aluminum molds ? i would like to try it out too

#32

Freekote works with aluminum and epoxy molds.

Definitely worth a try. One of the best releases in my opinon

#33

a simple Tackifier can be obtained by mixing a small amount of resin with MEK, Acetone, etc. and make a sprayable solution.
when the vehicle (MEK) evaporates the cloth will be tacky

the trick is in the delivery. spray gun/pre-val/spray bottle

#34

we did this for the first ply on metal tooling. The prepreg wouldn’t stick to the metal so it needed tackifier. Ours was some of the resin dissolved in acetone and then just sprayed with a spray bottle. Then you waited 5 minutes or so for it to fully evaporate. WOrks but, if you’re doing a dry layup this would not work. I think I’d rather use 3m 77 or some other off the shelf brand.

#35

That’s a very interesting and far more economical solution than using spray tack. Does anyone else have experience doing this? When you say resin + acetone, you mean the uncured resin part without the hardener, correct?

I’d imagine that if you’re using it on prepreg, acetone on it’s own would be enough to tack up the surface layer and the dissolved resin didn’t play too much of a roll, right?

#36

This is pre-preg, so the resin is already A+B.

SO the resin used is the same as in the fabric. It comes in a bag for dissolving in acetone. It’s a solid that we keep in the freezer and then smash it up and mix it into acetone to use as tackifier.

You can’t do this with room temp resin as it would just turn into nothing. You have to mix A and B parts for room temp stuff and if you mixed in acetone it would mess with the cure and physical properties of the cured resin.

The acetone would do nothing for tackifier as it evaporates so fast. The tackifier is applied to the metal mold for the first ply only. You spray it on, the acetone flashes off and leaves the resin behind, which is sticky. THen the first ply is laid down, and debulked.

Just throwing the info out there, but this is a pre-preg specific process.

For dry fiber, I always use a spray tackifier.

#37

Hey guys, rad about loads of gd stuff about frekote. Planning to move to semiperm release as im gonna wonder into prepreg world. :slight_smile:
One question, i checked the krayde website and the price for 1 gallon ( i believe its nearly 5 liters) frekote nc770 was $84. Am i correct about the price and the amount?
I live in Turkiye and had a henkel rep yesterday and he gave price for a gallon frekote nc770 and it was about $450+vat.

#38

450… damn… maybe cause the shipping over seas as a hazardous chemical? Or maybe it’s robbery?

Yah $84/gal sounds about right.

#39

Pure robbery her mate. Hate it :slight_smile:
Wish krayden can ship to turkey :slight_smile:

#40

Got the frekote mold sealer, how do I use it though?