All About Pocket Knives

What adhesive works the best for attaching scales to a liner?

KAC CUTLERY wrote: ↑Mon Jul 15, 2024 4:25 pm What.....

Maybe more appropriate here:
viewforum.php?f=37

I use a gel type cyanacrylate glue, and clamp it until it's set. It works quite well for me when I don't want to pin scales in place. I even use it when I'm going to pin the scales, to hold the scales in place while I'm shaping them, until I can pin the handles in place. Sort of a belt-and-suspenders solution.

KAC CUTLERY wrote: ↑Mon Jul 15, 2024 4:25 pm What adhesive works the best for attaching scales to a liner?

I'm sure there are many opinions on the answer to this question. My personal favorite adhesive for scales is Bob Smith Industries 5 minute Quick-Cure epoxy. (I think that Dale Orvet may have turned me on to Bob Smith epoxy a long time ago.) But, more important than they type of adhesive you are using is the preparation of both surfaces. I sand the outside of the liners and the inside of the scales in a cross-hatch fashion with 60 grit, then give both parts a good rub down with rubbing alcohol before mixing the epoxy, and then I'm very careful not to touch either surface with my fingers before putting the parts together. (The least bit of oil from your fingers can ruin the epoxy bond.) And, no matter how strong the adhesive bond is, I still pin all the scales before assembling the rest of the knife.

Let me second what Herbva said about prepping the material first. Prep work is key. No adhesive will stick well to materials that are too smooth, or that have oil on them. Sometimes sanding can even leave microscopic traces of silicon on surfaces that can prevent good adhesion.
For adhesives, I usually use Gorilla Glue, Gorilla Glue clear, and various cheap epoxies. The original Gorilla Glue holds better than even many epoxies, but it foams out of every crevice. The clear is much easier and cleaner to use, but I don't think that it holds quite as well. Still, I do not rely on the glue alone. I always pin the handles as well, and mainly use the adhesives to seal the scales to the liner and prevent moisture, oils, and grunge from building up underneath the scales.

Herb's advice for prep work is spot on, regardless of the adhesive you use.

A slow cure epoxy is best. I use West System's G-Flex as it has great heat resistance as well as excellent holding power. I pin everything as well. I wouldn't rely on cyanoacrylate as my sole bonding agent for knife handles. It doesn't like heat or shocks from dropping and fails when flexed as well. Just look at all the shields that are missing from knives for evidence of how good the bond is. It's fine as an intermediate bond before pinning though.

Eric

I use slow dry jb weld mostly. Although I Attached Buffalo horn scales on a fixed blade I made with jb and after about a year the ends came loose and popped up. I took it apart, sanded handles flat again, re prepped them and attached them with panel bond. We used panel bond to attach roof skins on trucks and cars in the body shop I worked at. Still holding 10 years later. I always prep with 40 grit and small angle drilled holes.
Jimbo

Oledadsknives wrote: ↑Sat Jul 20, 2024 5:54 pm I use slow dry jb weld mostly. Although I Attached Buffalo horn scales on a fixed blade I made with jb and after about a year the ends came loose and popped up. I took it apart, sanded handles flat again, re prepped them and attached them with panel bond. We used panel bond to attach roof skins on trucks and cars in the body shop I worked at. Still holding 10 years later. I always prep with 40 grit and small angle drilled holes.
Jimbo

Thank you.

ea42 wrote: ↑Tue Jul 16, 2024 2:25 pm A slow cure epoxy is best. I use West System's G-Flex as it has great heat resistance as well as excellent holding power. I pin everything as well. I wouldn't rely on cyanoacrylate as my sole bonding agent for knife handles. It doesn't like heat or shocks from dropping and fails when flexed as well. Just look at all the shields that are missing from knives for evidence of how good the bond is. It's fine as an intermediate bond before pinning though.

Eric

Thank you

Oledadsknives wrote: ↑Sat Jul 20, 2024 5:54 pm I use slow dry jb weld mostly. Although I Attached Buffalo horn scales on a fixed blade I made with jb and after about a year the ends came loose and popped up. I took it apart, sanded handles flat again, re prepped them and attached them with panel bond. We used panel bond to attach roof skins on trucks and cars in the body shop I worked at. Still holding 10 years later. I always prep with 40 grit and small angle drilled holes.
Jimbo

Thank you

beresman wrote: ↑Mon Jul 15, 2024 10:53 pm Herb's advice for prep work is spot on, regardless of the adhesive you use.

Reverand wrote: ↑Mon Jul 15, 2024 10:32 pm Let me second what Herbva said about prepping the material first. Prep work is key. No adhesive will stick well to materials that are too smooth, or that have oil on them. Sometimes sanding can even leave microscopic traces of silicon on surfaces that can prevent good adhesion.
For adhesives, I usually use Gorilla Glue, Gorilla Glue clear, and various cheap epoxies. The original Gorilla Glue holds better than even many epoxies, but it foams out of every crevice. The clear is much easier and cleaner to use, but I don't think that it holds quite as well. Still, I do not rely on the glue alone. I always pin the handles as well, and mainly use the adhesives to seal the scales to the liner and prevent moisture, oils, and grunge from building up underneath the scales.

Thank you