3M Super77 Not Compatable With Resolene?

[TinkerTailor]

I have had 2 really weird glue failures recently with 3m super 77. Both related to sealing the flesh side with resolene and then gluing in a liner. I have used super77 for years and never had a problem like this.

I used it to attach some silk liners to some wallets i did, Some in Chromexcel, Some in veg-retan latigo, a hotstuffed but pretty dry and stiff leather. I have had issues with the glue sticking to horween, but never with either leather if i rough up the surface sufficiently. I glued the silk down a little over a week ago, and it was stuck like normal, 2 days later when i stitched 1 of the wallets, the glue was still stuck hard like it should be.

Yesterday I went to stitch another wallet (they were all glued at the same time), and all of the glue had failed on all the wallet liners.

It turned to goopy slimy stuff. Really stringy with no hold at all. The brush on adhesive i used on the leather/leather edge glueing was fine.

Thing is i have used this fabric and leather and glue together before, and had no problems. I carry a wallet made this way.

The only difference is this time I 50/50 resolened the backs 2 light coats to prevent rub off from the leather. Occasionally my white business cards get discoloured in my wallet. I did this at least a week before glueing, i have been bit before by not waiting enough for things to dry.

The adhesive in the test piece I did with silk and chromexcell using lepage heavy duty brush on contact cement on top of resolene is perfect, however it is impossible to brush the adhesive onto this silk without it distorting the pattern or soaking through. I pretty much have to spray it. And I know from experiments that you can not spray one side and brush the other with these products. It turned goopy as well, right away.

I think this is caused by one of two things,

Either that some kind of reaction happened over time between the resolene and the 3m super77 spray adhesive.

Or that the fumes from the brush on contact adhesive killed the super77. I do find this unlikely as the area they were in was well ventilated and there was at least 2 days between lining the backs and adding on the side pieces, plus i have done this successfully without the reso. but it may be the case.

I am going to test this properly in the new years and report what i find, as these are commonly used products.

In the mean time, anyone else seen this kind of thing?

Edited December 21, 2015 by TinkerTailor

[Art]

You cannot spray something "hot" over something "cold".

"Hot" is something with very volatile solvents.

"Cold" is anything with less volatile solvents than the "hot" you are mixing it with.

When the "hot" is on the bottom, you can let the solvents evaporate completely. just like they are supposed to. Then you can apply 'cold" to the top without it redissolving the "hot" bottom coat.

When you put "cold" resolene (water based) on the bottom, even letting it dry for days, a "hot" top coat with aggressive solvents will start to attack it. It might not happen right away, but the process starts immediately, and will eventually effect the "cold" bottom coat.

Anyone who does automotive finishing has figured out what happens with enamel and lacquer, well, it is kind of the same with the leather finishes and is now creeping into the glues we use.

If you want to countermand this basic principle, you have to get into mixing in things that harden (hardener maybe, or a cross-linker) the "cold" product. This gets even more complicated in the shoe repair industry, where some of the sole material is "cold" compared to the "hotter" glues.

Art

[TinkerTailor]

I kinda knew you would be the one with the answer, Thanks, I also suspected the resolene on the back was a belt and suspenders thing anyways.

I guess for now when i make my hipster wallets, if the colour gets through the glue and silk, just let em bleed......

[Art]

Contact cement is usually natural rubber (or maybe Neoprene) that has undergone strain crystallization. This will be pretty much impervious to most things if coverage is complete. I am not sure what 3M 77 uses.

Art

[stelmackr]

You cannot spray something "hot" over something "cold".

"Hot" is something with very volatile solvents.

"Cold" is anything with less volatile solvents than the "hot" you are mixing it with.

When the "hot" is on the bottom, you can let the solvents evaporate completely. just like they are supposed to. Then you can apply 'cold" to the top without it redissolving the "hot" bottom coat.

When you put "cold" resolene (water based) on the bottom, even letting it dry for days, a "hot" top coat with aggressive solvents will start to attack it. It might not happen right away, but the process starts immediately, and will eventually effect the "cold" bottom coat.

Anyone who does automotive finishing has figured out what happens with enamel and lacquer, well, it is kind of the same with the leather finishes and is now creeping into the glues we use.

If you want to countermand this basic principle, you have to get into mixing in things that harden (hardener maybe, or a cross-linker) the "cold" product. This gets even more complicated in the shoe repair industry, where some of the sole material is "cold" compared to the "hotter" glues.

Art

Art,

Your Hot & Cold statement is now printed and hangs in the area by my finishes.

Thanks.

Bob Stelmack

[mlapaglia]

Try thinning and spraying something like clear lac instead of the Resolene. This should not react to the 3M 77 since Clear Lac is "hot".

[TinkerTailor]

Try thinning and spraying something like clear lac instead of the Resolene. This should not react to the 3M 77 since Clear Lac is "hot".

I will try that, thanks for the tip. The weird thing is that the super77 reacted this way and the lepage heavy duty contact cement has no issue that i can see. It is the same as weldwood red apparently. It is the canadian version. I am not home for the holidays, when i am back in the shop, I am going to do some research into which solvents are in which because i don't think it is a hot/cold issue in general, more so a particular solvent in the super77 that is used as a propellant or a thinner. The super77 does smell for alot longer than the traditional contact adhesive, perhaps one of the solvents has a longer volatile time before it evaporates causing the effect (or increasing it)