Update 4/28 Best glue plastic hotel key card to balsa?

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BABAR

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I am going to scuff up the surface of the key card pieces.
Is best glue epoxy, wood glue? Something else?
 
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Either epoxy, or a polyurethane glue like Gorilla Glue. Definitely not wood glue. I would recommend testing on some scrap pieces first.
 
Pacer Formula 560. At least if you're looking for something that sticks well but is a bit flexible when cured. I use this stuff for just about all my plastic-to-something else in my rocketry and model airplane endeavors.

What is your application?
 
Epoxy would be worth a try if you have some to test. I have used polyurethane glues with success on plastics, but they can end up looking pretty awful as they expand. PL Premium construction glue does not expand as much as Gorilla glue and is easter to smooth out. I have used it on gluing a wide variety of materials to PET water bottles.
 
So, are you saying that your credit score is soaring?
[EDIT]Miss read that... that's a hotel key card not a credit card.
 
Either epoxy, or a polyurethane glue like Gorilla Glue. Definitely not wood glue. I would recommend testing on some scrap pieces first.

I like both ideas
I have a test piece with gorilla glue, 5 minute epoxy, wood glue, and thick CA curing, will report tomorrow
 
I'd make a bunch of tiny holes on the root edge and use epoxy / fillets and have them 'pinned' in place with epoxy in the holes.
 
I'd make a bunch of tiny holes on the root edge and use epoxy / fillets and have them 'pinned' in place with epoxy in the holes.

These are not fins, they are kind of like braces. They will be flat side to flat side. Could still put some extra holes in them though.
 
I used to use hotel cards for fin material on small contest models. Medium thickness super glue worked best to keep them attached to the tubes, so I would imagine for what you are doing, that would work well too.

kj
 
These are not fins, they are kind of like braces. They will be flat side to flat side. Could still put some extra holes in them though.

As these are NOT fins, then Nathan's response is spot on. I might suggest you find some way to clamp the plastic as the adhesive dries/cures

Either epoxy, or a polyurethane glue like Gorilla Glue. Definitely not wood glue. I would recommend testing on some scrap pieces first.
 
Epoxy will not stock to these. (That's why I use them to do my fin fillets, bend 'em and the epoxy breaks right off! scrapes off too, nicely, with a dull knife.. )

scuffing them (scuff the crap outta them!), holing them will help, but epoxy & the shininess of the cards don't mix.

Are these (hotel room keys) the best for your application? why not wood? or cardboard? Styrene sheets will sick best with CA. I would think wood is stiffer, and bonds better than plastic (and is marginally lighter)
 
Test results
I tried five minute epoxy, polyurethane gorilla glue, wood glue, and CA
I roughed up the card pieces
Polyurethane and epoxy both held well. The polyurethane has the problem of swelling up, and little tiny flecks that get overlooked when glue is placed grow up into ugly bumps when cured. So bad for exposed surfaces, also not good for areas that need to be smooth.
The wood glue and the CA broke off immediately.
 
Sorry for the short post, but when I've recommended MMAs in the past, the post usually just gets ignored. MMAs - Methyl Methacrylate Adhesives - are similar to epoxies, but are formulated to work on plastics, even some of the harder to bond plastics. Normal epoxy just surface bonds to plastics, which is why you need to rough it up before bonding. MMAs attach to the plastics chemically.

The adhesive that introduced me to MMAs was Devcon Plastic Welder. https://www.tapplastics.com/product/repair_products/adhesives_glues_sealants/plastic_welder/278 Yes, the fumes are a bit much - use in a well ventilated area.
 
Thanks. I figured out what MMA was (okay I googled MMA and glue and figured it out!)

But I appreciate the link because I wasn’t sure what I could get in the store

Looks like they have this at my local store.

I will give it a try!
 
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