[Jason Russell]

I was reading in my blade mag about epoxy. I have been using 2 ton epoxy with a 4 hr cure time. The article was talking about a loctite bonding agent that doesn't get completly hard like regular epoxy. Does anyone know what kind this is. the way i took it was it stay somwhat plyable for the shrinking and expanding off the handle material.


FORGE ON!!
Jason Russell

[Lin Rhea]

You're going to get a variety of opinions Jason. Some buy based on local availability, some on experience gained from other fields such as gun making. As far as epoxies, I stay away from the extreme fast cures except for temporary applications. For the final glue up, I use the slow set. You may have to try different brands to see what works for you. I like Devcon, West Systems, and RAKA inc. As with many thing, you get what you pay for and in this case, you get what you WAIT for.

[Dwane Oliver]

Tell us why you think the fast cure's are not good Lin.
I have been using the Devcon 5 min epoxy for years with great results.

[Brian Thie]

I use Acraglas from Brownells. The reason for this is that it has a long shelf life, has been around forever (since 1959) and has a great reputation, it is designed to hold up for a lifetime, and has great strength.

Shelf life is a big consideration. Regardless of what you use, you need to know the shelf life. Many epoxies have a shelf life of only a few years to only several months.

from Brownells site :
Storage - Store in a cool place (68°-72° F.). Shelf life of unmixed ACRAGLAS
components is Fifteen to Twenty years.


Brian

[Lin Rhea]

I dont mean to influence your choices of epoxy Dwane. If you like the fast set, use it. I like the extra time the slow set gives and I do think it's stronger in general. I might be wrong about that in some cases. It might just be that brand of fast set that I was not happy with. I do know that I've been happy with the result of all the slow set I have used. Once I have a bad experience, I tend to avoid that again.

[Steve Culver]

I can't find it now, but I once saw a test on a bunch of different epoxies. The fast cure time epoxies had a tendency to break down over time and crystallize. Too, they do not withstand heat as well.

I use Acraglas. Being a gunsmith, I have used Acraglas to install barrel liners, literally gluing the barrel liner inside a drilled out barrel. I once had to remove a barrel liner, that I had just installed, when the customer changed his mind about what caliber he wanted the gun to be. I expected that I could just heat the barrel to burn out the Acraglas, then drive the liner out. I started with heating the barrel to 350 degrees; didn't work. Increasing the temperature 50 degrees at a try, I finally got the Acraglas to give up at 500 degrees. Note that Acraglas is designed to withstand the hot caustic bluing process. I have many times installed barrel liners and then blued the barrel in 300 degree hot caustic bluing solution.

There is an interesting thread on BladeForums, where different adhesives are tested. The thread is titled "Glue Wars".

[Jason Russell]

I like the slow cure because I'm a nitwit and need a little more time to get things together. Thanks for the info. I've heard of the Acraglas before, mighht be worth giving it a try.

FORGE ON!!!
Jason Russell

[Mike Williams]

What Steve said on the accraglas. It is good stuff.
Mike

[Cheyenne Walker]

Steve,
I looked at Brownell's website. I seen Acraglas and Acraglass Gel. Does one work better than the other?

[Steve Culver]

The regular Acraglas is what you want. I buy it in the 28oz. resin and 7oz. hardener shop kit. That's a lot of epoxy, but it has a long shelf life. Use it for any household epoxy chores to use it up.

I've seen some comments on how Acraglas needs to be mixed to exact proportions to work. This ain't so; no more than any other epoxy. It is just mixed four parts resin to one part hardener, instead of one to one like most epoxies. I use 3oz. plastic "Dixie" cups to mix my epoxy in. I put the amount of resin in the cup that I want, then just eyeball the amount of hardener. The resin is clear and the hardener is yellow, so it's easy to see. I've never had any problems with it setting up.

One thing I have noticed about Acraglas is its tendency to get a lot of air bubbles in it when you mix it. You don't want air in your epoxy any time, as this will result in an incomplete fill between your handle and tang. Acraglas seems to be worse than most epoxies at whipping up into a froth if you stir it fast. But, since Acraglas doesn't start setting up for at least 20 to 30 minutes, I just let it set on the bench after mixing for about 10 minutes and most of the bubbles are gone.

[Ed Caffrey]

Hi Folks!

I can address the issue of why I will not use anything other than acraglass, and why I simply don't not like any of the fast set epoxies.....

When I first starting, I used Devcon 5 min epoxy.....fast forward to about 6-7 years later....I started getting phone calls from customers, telling me the the handles on their knives were "loosening up". I repaired/replaced several handles....and started searching for answers. After a number of phone calls, I found an Chemist at Devcon's parent company that would talk to me. After relying my experiences, the individual sort of chuckled...he said "Let me guess...those knife handles had been glued for about 5 years?" UH?? Yes. As crazy as it might sound, he went on to tell me that Devcon epoxies are chemically engineered to start breaking down at the 4-5 year point. WHAT!!!????? Then he went on to say that his job is dependent on people buying epoxy, and that they want us to purchase more, so they are not going to sell an epoxy that lasts forever. Guess that makes sense when looked at from a perpetuating business aspect.
I also got the skinny on shelf life.....NO longer than 6 months from the date of manufacture.

So, moral of that story is, if you choose to use Devcon epoxies on your knives, don't be surprised if you get phone call from angry customers in about 4-5 years after you sell them a knife....with complaints of loose handles, or even handle scales coming off!

To date, there are only two "epoxies" that I would use or recommend for knifemakers.....1. Acraglass. It's simply the best for our application, 10 year shelf life, and 50 year hold life. 2. West System Marine Epoxy....it has a hold life of 20 years, and a shelf life of 5 years. Many balk at the cost of the shop kit of Acraglass that Steve mentioned (28oz resin/7oz hardener), but it is considerably less expensive that buy all those little double syringes.

Learn from my experience....do yourself a favor and if your using Devcon, or any of the other locally available epoxies, get rid of them and go with either of the "glues" I mentioned.

[Lin Rhea]

Very valuable information Ed and Steve. I intend to make the change in my enventory asap. I have and use several, but the Devcon will be phased out. I depend very little on epoxy anyway since I mill my slots so close to fit the tang, but some handle constructions require the open voids to be filled. This also speaks to the value of mechanical fasteners. Pins, bolts, finial type fasteners. etc. of which I am a big believer.

Edited to add: I just ordered some Acraglass. I will still use the RAKA I have. It's good stuff. One can never be too prepared.

[Dwane Oliver]

WOW ,thanks for the info Ed. I too will be changing.
I have had no calls ......YET. But better to be safe than sorry.

Dwane

[Cheyenne Walker]

Steve Culver, on 04 March 2012 - 08:55 PM, said:

The regular Acraglas is what you want. I buy it in the 28oz. resin and 7oz. hardener shop kit. That's a lot of epoxy, but it has a long shelf life. Use it for any household epoxy chores to use it up.

I've seen some comments on how Acraglas needs to be mixed to exact proportions to work. This ain't so; no more than any other epoxy. It is just mixed four parts resin to one part hardener, instead of one to one like most epoxies. I use 3oz. plastic "Dixie" cups to mix my epoxy in. I put the amount of resin in the cup that I want, then just eyeball the amount of hardener. The resin is clear and the hardener is yellow, so it's easy to see. I've never had any problems with it setting up.

One thing I have noticed about Acraglas is its tendency to get a lot of air bubbles in it when you mix it. You don't want air in your epoxy any time, as this will result in an incomplete fill between your handle and tang. Acraglas seems to be worse than most epoxies at whipping up into a froth if you stir it fast. But, since Acraglas doesn't start setting up for at least 20 to 30 minutes, I just let it set on the bench after mixing for about 10 minutes and most of the bubbles are gone.

Steve,
this is what's listed that you get with the shop kit:


ACRAGLAS SHOP KIT - 28 fl. oz. (828 ml) Resin, 7 fl. oz. (207 ml) Hardener, 3 fl. oz. (89 ml) Release Agent, 8 oz. (227g) Floc, 24 3 oz. capacity Mixing Cups, 50 Mixing Sticks, 5 Packets Brown Dye, 5 Paks Black Dye and Instructions.
For $98.99 at Brownell's.

For $67.99, I can get the 28 oz resin and 7 oz. hardener. Is the rest of the stuff worth the extra $31? I doubt that I need the dyes, and I already have 3oz cups and popsicle sticks for stirring. So I'm just concerned about if I need the release agent,(if it's for getting the stuff off my hands, I will need it )and the floc. Um, what is floc anyway? I asked Google and didn't find an answer that fit when dealing with epoxy. Evidently, Google is not all knowing after all. Or maybe it's just me.

[Josh Fisher]

thanks for the info, I came on here to put my two cents in & after reading Ed Caffrey's post, I'll have to get some of that Acraglas

[Brian Thie]

Cheyenne

You can get by with the resin and hardener only. If you want Dye, you can purchase that seperatly for $6.00. Flock is just a filler material that you can mix with the Acraglas for filling large voids when bedding rifles. It is kind of like adding fiberglass to concrete to add strength -- but it is not needed for knives.

The release agent is again designed for the gun bedding. It is designed to keep something from bonding to something else. Although there are times where it could be used in knifemaking, most people use vasaline.

Check out this link from Brownells for Acraglas instructions.

AcraGlas instructions

Brian

[Steve Culver]

Just the Acragas, not all of the other stuff. Sorry about that, didn't think about it giving you the rifle bedding kit option. The release agent is used on a rifle action to keep the Acraglas from adhering to it, when glass bedding the action into a rifle stock. It would work well on a blade tang, if you are building a take-down knife. Other than that, you don't need it.

[Ed Caffrey]

Something that bears mentioning about Acraglass is....it is NOT mixed as typical epoxy is mixed. Acraglass is mixed 4 parts resin, to 1 part hardener. When I first started using it, I purchased a batch of the graduated mixing cups...by the time I had used them up, I had it down "by eye".

Some folks have gotten themselves in the habit of mixing the standard 50/50 epoxies with a tad more hardener, hoping to make it "kick" faster... DO NOT do that with acraglass! If you add too much hardener to acraglass, it will reach the consistency of jell-O, and never get any harder. I've gotten myself in the habit of sitting the mixing cup next to the knife I just put a handle on...there's always a bit left over...and if it cures correctly, I know everything is good.

Personally, when it comes to dyes being used in acraglass, I will only use the dry (powdered) variety. I experimented a few times with using liquid dyes, and never had good results. I like the powdered dyes that K&G sells.

[Cheyenne Walker]

Thanks Brian and Steve. I will get it ordered.

[Karl B. Andersen]

I use the West System epoxy. I appreciate the calibrated pumps.
It's a marine epoxy, and if you think of it - it's meant to hold boats together and as the coat that adheres the fiberglass sheets to hulls!
It's UV resistant and impervious to solvents and cleaners that one might find around a marine installation.
And the excess just wipes off with denatured alcohol for nearly an hour after application.
I have no desire to use anything else.