When do you use spray adhesive and what kind to use?

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#21

The airtac stuff works best, on complicated parts the notion to use it makes sense but it can cause release issues if over used. I remember having an employee begin on the lay-up sequence, it was first time doing it on his own. He had 4 moulds to lay up that day…Needless to say, we should of watched more carefully, the parts were not large, maybe 2.5 feet long by 1.5 feet wide…he used 4 cans of airtac…

We realized this at the end of the day when one of the other guys looked in the bin by the workstation and saw 4 empty cans…

The parts did not demould by the way, they were forced or cut out of the mould, only 1 of the 4 moulds was damaged so we actually were kinda lucky…

The idea is a light, light mist, like others gave stated, not directly in the mould but on the fabric.

#22

I have been wondering about this…If you have sprayed PVA on the mold surface and then spray some adhesive and stick carbon, and then the piece of cloth shifts a bit, will this not take the PVA with it, and break the mold release barrier?

#23

Yes it will, thats why it is a good idea to use a gelcoat.

I tested hairspray two days ago.
Result: No tack and delamination problems! Hairspray does not work!

#24

DD well that has saved me from pinching the wifes hairspray and giving it a try. I think I will stick to the 3M 77

#25

Yes, it will.

In an ideal world:

-1. you do not want to use PVA, except for very specific reasons.
-2. you do not want to use spray glue on the surface of your product.

Use a gelcoat, have it tack up, then apply the fabric, then add more fabric, using spray glue only when needed, and only in the least amount possible.

#26

I bought a can of it to try. I threw it in the trash after two applications. Problem is this - it spits like mad. No matter how you shake it or how clean you keep the tip, it spits and hisses for a very uneven application. A total PITA.

I use AirTac2 or 3M Super 77. There are lots of spray adhesives meant for fabric that probably work. Anyone try Sluyter Featherspray 470? About 1/3 cheaper than Airtac2.

http://www.cansew.com/product/428.aspx

#27

I agree with the Stayz comment. It’s doesn’t spray. It pees. However it is the only thing I have found that sticks mold that has been treated with Enviroshield. Econotack doesn’t stick to it at all.

What surface release agents are you using and what spray tack will stick with them?

#28

It spits and pees because of it’s tip.Remove the tip and use a classic one from a color spray can and it will flow better.