Glue

[MoSmith]

What kind of glue is good. I've used Gorilla epoxy and when I had to remove a handle I had to use a chisel and hammer. I'm trying JB weld epoxy right now but have no experience with it. I use at least a couple of pins and usually more if that makes a difference. Is there something out there that does a better job?

 

[3fifty7]

West Systems GFlex epoxy is the overwhelming go to. They offer different cure times.

 

[Sando]

There's two purposes for 'glue'. One, to keep the scales affixed to the tang (or the handle for a hidden tang). Two, to keep moisture from seeping into the handle (scales, liners, pins, guards, etc.) Some argue that purpose one is not correct and you have to rely on a mechanical bond, like screws or peening. I don't go near that debate.

If you want the strongest bond in the universe for purpose one: Loctite Hysol E-120HP (available on Amazon, Grangers, etc.) It's used in aircraft manufacting, for goodness sake!

The problem is that most handle materials expand/contract at different rates than steel. So for a knife it might not be the best choice. If the materials are too well affixed, it might fracture the handle material (in theory) at some point in the next 100 years.

I'm with 3fifty7 . An epoxy with a little 'flex' is what you want. I've switched from Hysol to GFlex myself. You can't feel or see the flex in the hardened product, but I'm assuming it'll help. I like the consistency of it while applying and it has the right amount of 'wetting' while you spread it. The dimensional stability (filling voids) seems fine too.

 

[TheEdge01]

What kind of glue is good. I've used Gorilla epoxy and when I had to remove a handle I had to use a chisel and hammer. I'm trying JB weld epoxy right now but have no experience with it. I use at least a couple of pins and usually more if that makes a difference. Is there something out there that does a better job?

I have used the 5 minute two part epoxies from Gorilla and Loctite myself, and they seem to get the job done. Nowadays, I mostly use G-Flex or the 30 minute cure epoxy from Pops Knife Supplies.

 

[Taz]

I use JB Kwik Weld and Devcon or JB Plastic Welder on most of my handles. I had to chisel apart handles and grind the remainder off on 2 I redid recently using these epoxies. On another one using the Devcon Plastic Welder I made 20 years ago, the Micarta split before some of the glue let go! I want to try the LocTite Hysol stuff. I like the Kwik Weld/Plastic Welder because I can shape the handle in 15-30 minutes, depending on the temp it cures in. And it's easier to keep the glue from seeping out from the front end of the handle since it cures quickly.

 

[Stacy E. Apelt - Bladesmith]

My go-to resin is System Three, which is pretty much the same as West System.
I have started experimenting with Total Boat Flex-Epoxy. Seems really strong and suited for our use.

 

[tim37a]

Hi Stacy,
I was one of the original recommenders of G Flex several years ago and still use it, with no failures to date. I have not seen the Total Boat FlexEpoxy before but it sounds pretty good. Please give us a report of your test results. Will you try it on copper, brass, and bronze also. They are often difficult to bond with regular epoxies. Thanks.
Tim Barney

 

[AVigil]

Gorilla Glue High Impact Super Glue.
Readily available, great impact strength

 

[David Mary]

Gorilla Glue High Impact Super Glue.
Readily available, great impact strength

I've used it and it really is great. Even in my hard use choppers. I have switched now to Gorilla Glue white, as it is water proof, and not just water resistant. It is also incredibly strong and holds up in my choppers.

 

[Joshua Fisher]

I've used it and it really is great. Even in my hard use choppers. I have switched now to Gorilla Glue white, as it is water proof, and not just water resistant. It is also incredibly strong and holds up in my choppers.

Do you mind sharing your process for the gorilla glue white? I’ve been experimenting with one part finishes over mixing epoxy. One concern I’ve had with the gorilla glue is it says to dampen one surface and I wonder if that would create rust under the scales with carbon steels. I’d also be curious as to how long you really have to let the gorilla glue dry before you can start shaping everything.

 

[Natlek]

Hi Stacy,
I was one of the original recommenders of G Flex several years ago and still use it, with no failures to date. I have not seen the Total Boat FlexEpoxy before but it sounds pretty good. Please give us a report of your test results. Will you try it on copper, brass, and bronze also. They are often difficult to bond with regular epoxies. Thanks.
Tim Barney

When you find something that work for you there is no reason to search for other thing . At least that is how I do that .I use same epoxy all time , and I don t care if there is BETTER epoxy .Same with belts , Klingspor belts do what I want and I don t give ***** about other brand belts .

 

[Jason Fry]

Somebody say G Flex yet lol?

 

[Horsewright]

I've used it and it really is great. Even in my hard use choppers. I have switched now to Gorilla Glue white, as it is water proof, and not just water resistant. It is also incredibly strong and holds up in my choppers.

Do you mind sharing your process for the gorilla glue white? I’ve been experimenting with one part finishes over mixing epoxy. One concern I’ve had with the gorilla glue is it says to dampen one surface and I wonder if that would create rust under the scales with carbon steels. I’d also be curious as to how long you really have to let the gorilla glue dry before you can start shaping everything.

Try the Gorilla Glue Clear. Don't need to dampen surfaces and no expanding foaming of the glue. It really works, I've use it exclusively on non bolstered knives for years. so thats quite a few knives and no problems. On bolstered knives I'm with Adam, I use the Gorilla Glue High Impact Super Glue. Thousands of knives and no failures. I can tell you the scale will fail before the bond does.

Getting the last drop out:

Bolstered knives glued up:

Ya switch to these guys and ya can see Willian Wallace all painted blue, running around in the background yelling "FREEDOM!", from the epoxy mixing blues/mess.

 

[David Mary]

Try the Gorilla Glue Clear. Don't need to dampen surfaces and no expanding foaming of the glue. It really works, I've use it exclusively on non bolstered knives for years. so thats quite a few knives and no problems. On bolstered knives I'm with Adam, I use the Gorilla Glue High Impact Super Glue. Thousands of knives and no failures. I can tell you the scale will fail before the bond does.

Oh that's the stuff I was using. It says "high impact" on the bottle as well, so I thought it was the same thing Adam was suggesting. It works very well, and is super strong and convenient, and water resistant too. I never had any issues even when wet sanding handles after assembly. But when I started getting into making knives with LC200N I questioned its water resistance, so I left a knife I made with it in a container of tap water for 24 hours to see what would happen. The glue turned all jelly like, and the scales separated from the tang a bit. That's when I switched to white, so that I could truly say my knives were waterproof. And now I use it on carbon steel as well, just for a consistency in my build process, and the fact that it expands and is somewhat gap filling, which can be helpful for me as I shape everything freehand by eye with no jigs.

Do you mind sharing your process for the gorilla glue white?

I cut my scales, then stick them together with a dab of Gorilla Glue CA/High Impact, which Dave showed above and stick it in the vise for 10 seconds. Then I stick the blank to that using another dab and another crunch in the vise for 10 seconds. Then I take that out and drill my holes in the drill press. Then I use my putty knife to separate them, and clean off the surfaces of any residual glue with a quick hit on the grinder at 36 grit. Once the surfaces are clean, I have a yogurt container in my shop that has straight tap water so I get it on deck and open it up. Then I take one scale, put enough Gorilla Glue White on it to cover both scales, and put them two scales together, and rub them around until I have a flat and consistent layer of glue on each scale. Now I slide the top scale about halfway offset from the bottom one until I can pop it off and then I set them side by side "bookmatched" if you will. They say only a thin layer is required, and I find this to be true. I just make sure there are no spots that are not covered, and if either scale still has any spots on it with no glue, at this point I'll just put a drop on from the bottle.

From here, I take my pins, and one at a time I apply the Gorilla Glue white to the contact surface of the pin so it is covered, spreading it a bit with the glue bottle nozzle. Then I dip the glue covered pin ever so briefly into my water container, and insert the pin into one of the scales. Once I have all my pins in, I place the blank onto the scale, after dipping the tang up to the front pin hole in the container (and giving it a very quick shake or two to lose excess water), then place the other scale on top, turn the knife 90° (edge up) so I can lift it without anything trying to shift out of place, and attach my spring clamps.

I let my pins have ever so much play in the holes as well, so they are easy to put in without the need for hammering. This wasn't always the case, at least with G10 and synthetic handle material. With wood, always as long as I can remember, because years ago a guy had me repair a wood handled knife that had split, and I realized his pins were too tight. But now I always leave a tiny bit of play, even on my choppers, and have found the strength of the handle is perfect, probably thanks to the expansion of the Gorilla Glue white.

One concern I’ve had with the gorilla glue is it says to dampen one surface and I wonder if that would create rust under the scales with carbon steels.

I have been using it for carbon steel, and it's an interesting question. Due to the rapidity with which the white foam expands out of the tang and pin holes, I would guess the reaction is fast enough to avoid that being an issue. However, one thing I have had to carefully avoid is having so much water on the tang that it squeezed out at the ricasso, and goes beyond the glue, to where half an hour later I have rust spots on the ricasso. So I am now careful to look for any so I can wipe it off, and also let the knife cure with the point facing up so any excess water rolls down off the knife, or at least to parts of the handle yet to receive some material removal during shaping and finishing.

I cannot say 100% for sure that there is not any rust forming under the scales, because I have never managed to get the scales off again, outside of grinding them off, which I only did a time or two. But again given the amount of water and the speed of the reaction, I doubt it.

I’d also be curious as to how long you really have to let the gorilla glue dry before you can start shaping everything.

Gorilla Glue white says it cures fully in half an hour. And they aren't kidding! I can start grinding and shaping within that amount of time, once the foam feels dry and firm to touch.

I use my neck knife and sanding sponges to clean up the foam as best I can afterwards.

 

[Taz]

What do you recommend for the epoxy that squeezes out of the front of the scales? Can you clean it off with DNA/Acetone like you can with other glues before it sets up or does it keep foaming out throughout the process? Will acetone remove it when cured? I want to try this on some stuff with lighter color liners. My normal JB Kwik Weld is dark and makes lighter handle materials/liners look dirty/muddy and you can also see a thin glue line there too.

 

[Skiller1nc]

Try the Gorilla Glue Clear. Don't need to dampen surfaces and no expanding foaming of the glue. It really works, I've use it exclusively on non bolstered knives for years. so thats quite a few knives and no problems. On bolstered knives I'm with Adam, I use the Gorilla Glue High Impact Super Glue. Thousands of knives and no failures. I can tell you the scale will fail before the bond does.

Getting the last drop out:

Bolstered knives glued up:

Ya switch to these guys and ya can see Willian Wallace all painted blue, running around in the background yelling "FREEDOM!", from the epoxy mixing blues/mess.

So to be clear you are using CA glue and pins to attach scales and it's been working well for you for hundreds of blades and a long time? I figured the hardness and relative lack of shock resistance would make CA glue suboptimal compared to epoxy but if you are proving it works that's a game-changer as far as ease of use and time goes.

 

[David Mary]

I contacted CustomerCare@gorillaglue.com when I was looking at making the change and they provided me with their TDSes for CA, and dries white, which I share now below:

 

[David Mary]

Like Natlek said, some things may be "better" in terms of strength, but the questions I have are "will my knife ever experience those forces?", and "If not, will the cost or added time be worth investing if what I do has worked flawlessly so far?".

 

[David Mary]

For me, the answer was "yes" when switching to Gorilla Glue white, despite the extra half hour curing time, for the simple fact I can now say the adhesive is waterproof.

Here is a knife I made with CA:


It was an experiment, and I freehand shaped each handle piece from G10. It was my first time attempting it with so many and such small pieces. I didn't notice until during for some and after glue up for others I had miscalculated and some of them were not quite correctly shaped and I had gaps. Because of the fast cure time of CA, I had to roll with it, and ended up filling any gaps with CA.

I offered the knife for sale a couple times and it never went, so eventually I let it go in a half price sale, for something like $60 USD. Because the sale was a very busy day for me with lots of posting and emails, I unfortunately had it slip my mind to let the customer know the CA was not waterproof. I also subconsciously assumed since the blade was carbon steel, the customer would take the necessary care. Well that assumption did what assumptions tend to do, and bit me in rear end, when I saw first the customer had posted this pic:



And then later this pic:



This knife was made around the time I was starting to play with Gorilla Glue White, but the difficulty in using white for such a handle is that the longer cure time and expanding nature of the glue means that even when clamped, pieces can shift. I haven't found a perfect solution for that yet, but epoxy might be it. I have yet to get that ambitious again, though, and will leave that for the future once I catch up on pending obligations.

 

[Natlek]

It is little messy job but for scale gluing to tang best thing I ever try and test is automotive one component, high-modulus polyurethane sealant that cures on exposure to atmospheric humidity. You don t want to use pins ? Don t use them , and if EVER you need to remove that scales you will curse me for listening to me and used it , I guarantee it !
You can use best epoxy on world for scale gluing but I can pop off them easy , to easy if there are no pins .Epoxy can be flexible like rubber I will pop of them easy , and whole without damage. Don t get me wrong epoxy is more then good but this give you peace of mind , future user can do whatever he want with knife and scale would never ever fall .

Something like this

P645 PU Metal Sealant (Automotive-Construction) - Akfix

Akfix focused on developing eco-friendly, life-esteem chemical products and technologies to create permanent solutions for customer needs.

www.akfix.com