Attaching Scales

[wysixshooter]

Has anyone used Acraglas or Acraglas Gel (From Brownells Gunsmith Store) to attach scales to a fixed bladed knife? Particularly Carbon Fiber scales. And how well has it held up?

 

[Rusty McDonald]

Yep probably the best to use actually.

 

[silver_pilate]

Looking back to the glue wars posted here a while back, the Acragel failed early, whereas the regular, old two-part Acraglas was one of the best, especially for wood-metal bonding.

If it were me (and it is), I would (and do) use regular old Acraglas. I've been using it for a little while now, and I like it a lot. It is very tough stuff. It does mix a bit thinner than typical two-part epoxies, but that hasn't been a problem. Remember to mix by volume, not weight for Acraglas.

--nathan

 

[wysixshooter]

Sounds great thanks for the info

 

[silver_pilate]

A couple of things: it cures a very slight amber color, but I haven't noticed obvious glue lines between scales and handles. They do make dye you can use as well. I use a couple of syringes to mix correct proportions and rinse them out after each use. You need to go ahead and mix for a solid 4 minutes prior to application, and your working time is pretty good. Let it set up for most of a day prior to working it. Preparation of the mating surfaces is often times more important than the glue used. They should be clean, free of oils, and if you have access to a sand blaster, it makes a big difference. I don't have a blaster, so I use a 60 grit belt to get some good scratches on the scales and tang, and I take a drill bit and shallowly "pit" the scales and liners. That way I have contact from the scale straight through to the tang. I often drill holes in the tang as well to improve balance, and this allows the epoxy to reach from scale to scale. Acraglas works especially well for this, as it is designed to be a space filler.

--nathan

 

[Stacy E. Apelt - Bladesmith]

Acraglas is very good.
I have been using System Three T-88 with the same results. It,too, is a structural adhesive, meaning that it is designed as a space filler.

I have been experimenting with E-6000 lately. It is an industrial adhesive that is also used in the jewelry industry. As a one part adhesive, ease of application, and using only what you need is a real plus. It bonds most any material except a few plastics. I have found it super for bonding rubber/neoprene to steel. Its grip on steel is great. It is crystal clear, waterproof, dishwasher proof, and very resilient. Clean up is with acetone or citrus based solvents ( good for those who do assembly work in the house).

Whatever adhesive you use, you need to leave enough glue in the joint to do the job. Too many newer smiths ( and some older ones) clamp the heck out of a handle and squeeze all the glue out of the joint. This leaves the handle ready to pop off at the first sharp rap. This is called glue starvation, or a glue starved joint. There are several ways of avoiding this.

One is to drill many holes through the tang, making it a Swiss cheese style tang, and thus allowing glue "rivets" to connect the scales. This type of construction requires a structural adhesive. Done right, it can be used without any metal rivets, but I would not do that except for an art knife.

Another is to put many small shallow dimples in the tang and scales with a ball end mill ,drill bit, or ball burr on a dremmel. This makes many tiny pockets of adhesive to assure a stronger bond.

My method on full tangs is to "relieve" the tang by lightly hollow grinding all but the 1/8" around the edges. It doesn't have to look pretty, just relieve the surface a tad.This makes a shallow reservoir of adhesive completely under the scales. It only needs to be .010-.020 deep to assure a full bond. In my opinion, this is the strongest glue bond a handle can have. With the use of some pin stock rivets it will hold very well. Using Corby rivets will make it unbreakable without destroying the knife. The E-6000 adhesive seems perfect for kitchen cutlery and other users, as it works perfect for this construction style. Regardless of what type of papers you provide with your knives warning against putting custom knives in the dishwasher, people will do it. E-6000 is one way to avoid the repair problems caused by such abuse.

Stacy

 

[Bruce Bump]

Good advice Stacy,
Where can we buy E-6000? Does it have a wicking action? How long is the assembly time?

 

[Stacy E. Apelt - Bladesmith]

E-6000 is made by Eclectic adhesives, IIRC...............
yep - http://www.eclecticproducts.com/e6000.htm

It is available from craft stores in a tube, or from jewelers supply companies. It is pretty cheap,too. It is very similar to Shoe-Goo. It is a thick gel that is sticky. It does not wick at all as far as I can tell, but squeezes out nicely. Set time is 10-15 minutes, cure is 24 hours. Full strength is 72+ hours. As a sealant, it is superb. I haven't done it yet, but it should be real good for bolsters. Apply, squeeze out the excess and peen the pins. The joint would not show and there should be no possibility of capillary action of moisture or contaminants under the bolsters.

On things like repairing an old folder with a lost scale, the new scales could be applied with it and there should be no concern with scales popping loose due to the slight flexing of the liners.

Stacy

 

[Redrummd]

I use Loctite 324 and 325 for stone to metal. It is very fast setting up so you have about a minute to get it right. It is very simple to use with a spray on activator that I spray directly onto the stone. I then spread the 324 or 325 on the liner and mate the two together and work quick to get them lined up properly. I clamp the stone to liners for about 5 to 10 minutes and move on to cleanup with goof off of any squeeze out from the well, rocker arm and springs as appropriate to the knife I an working with.

I acrtually had a buyer try to remove a stone scale from one of my knives without asking me about how, or even if, it was possible. I have attached his results. (The repair cost him nearly what I charged him to do the knife the first time.)