Testing for the ultimate adhesive

[fitzo]

Not being a wiseguy, but your volume conversion sounded odd, so I found a conversion online:

50ml= 10.14 teaspoons(US) or 3.38 tablespoons(US) for whatever that's worth!

Useless trivia seems to be my forte!

[SteveS]

Funny guy

It appears that mistake doesn't adjust the cost per knife. Right?

Devcon about $.80
120Hp is about $1.44
Acraglas gel is $1.10
Acraglas is $1.34
Acraweld is $1.44
Shafting Epoxy is $.22
K&G 24 hour epoxy is $.22

The K&G stuff keeps looking better.

Steve

Steve

[fitzo]

Probably not very funny, but wisearse, yes! I suppose that signifies I am getting over this virus, finally. That's a good thing!

Your point is well taken: this is one place where economizing produces minimal savings and may well prove bad for the final product. Not worth taking that chance.

The only thing I don't like about the K&G epoxy is it is one of those intended for preparing by weight. There are some epoxies where minor discrepancies in mix ratios drastically affect the quality of bonding, so estimating volumes could be bad unless one takes the time to get it down properly through experimentation and can repeat that consistently. On the other hand, decent postal or food scales are only about $30 nowadays. Ray Rogers weighs his out into small tinfoil muffin tins for mixing and says it is great stuff.

[tmickley]

that is a much better cost comparison that I would have guessed. 64 cents/knife is nothing, especially given the vast improvement in performance.

[tmickley]

I was cleaning up the shop a little tonight and looked at the test piece I've been using. You may recall (or not) it still had marine epoxy, golf shafting and acraglass on one side, 3 different polyurethane glues on the other. Now this piece of soft steel had started to rust from the boiling and dishwashing. I saw that the acraglass had pulled away from the metal slightly, so had the golf shafting and marine epoxies. Most people would probably be curious about this, not me, it was just another excuse to whack 'em.
The golf shafting test piece of wood broke into 3 pieces and came off after three whacks. The marine expoxy came off with one whack. The Acraglass took a few whacks and it came off. The three remaining polyurethanes are still attached and they got double whacks. The #### things won't budge.

Here's the twist. This was stabilized wood by one of the best. It moved and pull its self away from the metal. It seems stabilized wood does not like to be boiled and dishwashed. I think the oxidation of the metal also contributed to the joint failure. The wood warping happened over the last couple weeks as that was the last time I had really looked at the test sample and there was no sign of it pulling away from the metal.

I here by declare Gorilla Glue winner of round one.

Round 2 starts when the K&G epoxy makes it here to be included.

[justice]

wow!! great thredd! i had been betting on the gorilla glue to do well even better then most would think. but winning the round was more then i expected! i was also betting on jb weld to do well.
the devcon i kind of figured would do about as well as it did.
which one was the best of the clear drys?

....justin

[SteveS]

Well that's one for the record books!

Tracy did I get this right. All the stabilized woods were damaged in the dishwasher? Was the Gorilla glue one damaged too? Did it just happen to stay on?

Steve

PS I've just finished up a new test bar (K&G, Acraglas Gel, 120HP, 05FL). Both sides of the bar were sand blasted. One side wiped with cotton rag and Lecto-clean (sp?) that other side with brake cleaner.

I'll send my sample glues to you on Monday for more tests.

[TexasJack]

...it was just another excuse to whack 'em...

Yeah, ya gotta love that!

Guys, y'all need to come up with some sort of grading system and rank the glues you've tested!

I didn't think it possible, but this thread could wind up longer than the Toastcutter contest thread.

[AcridSaint]

I just bought 4oz of gorilla glue for 8 dollars and some change. I was reading the bottle.. it says min 1/2oz per sq foot. I was thinking about my knife handles and I figure the knives I design as around 4"x1". meaning that the total surface area for one knife is about 8sq in. (2 sides). Correct me if I'm wrong here because I don't exactly pay attention to math, but there should be 144 inches in a square foot, so that makes 18 knives per half ounce (144/8) or 72 knives per bottle (at maximum efficiency). 72/9 (about 9 dollars for the bottle) is 8 knives per dollar or 12.5 cents per knife. Even if you can't use it most efficiently and/or you use bigger handles the cost is only a quarter if you double it. That's in line with K&G and the shafting expoxy... pretty cheap.

[tmickley]

Fitz, welcome back from the dead. Glad you are feeling better.

Steve, I think the boiling and then freezing while still soaked did the trick. Soaking/freezing did your last test in too. To be honest, it's hard to tell exactly what failed these last few adhesives. I just know they failed and the polyurethanes won. I have not yet tested my Loctite Speedbonder 324 like this. It has only done (an amazing job with) the load/sheer test.
Once I get the K&G from you, I'll glue up a bunch and we'll be starting round 2.

On the stabilized wood failing: This was some spalted maple burl that was extremely punky when I sent it off. Most of it was fine and useable but some, this stuff, was still just a little too soft for use but I keep it around for waste wood use. Some of it has taken insane abuse from my check faceted framing hammer. Some has just disintregrated from the boiling and the freezing. These latest pieces did move and pull away from the metal. I'm not sure what it proves other than stabilized wood will move in at least extreme conditions.

Jack, there will be a table (spreadsheet) on all of the adhesives with subjective grades or pass/fail assigned to various catagories when we are done. We will make it available some how. I doubt we will beat the toast cutter thread and if we threaten it, I'll break the thread in two. The toast cutter thread needs to be the biggest. Gabe earned that. We have made the top ten I think in views and #2 in participation which is cool. If you are curious, click on views or replies at the top of the columns. It will bring up some old threads you may have missed. They are still relavent I think. I reread some I had forgotten about.

Here is your chance to get in on the infamous glue wars....We'll need a host or two for the results.
If some one has a lot of spare bandwidth available for a few months, we need a host. I'm already running 40% of my bandwidth and I've even upgraded once. Once the initial mob of downloading has passed, I can host it if I can figure out how to. I use a wysiwig web site editor and I've made a determined and sucessful effort to not learn HTML. Basically it can be as simple as a download link or something you can view online or both would be great.

[SteveS]

Tracy, I have a new web site in the works. I'm sure I can host it.

Steve

[tmickley]

Glue up tips for the day.

When you are mixing up a 2 part batch of adhesive, save the cup or scrap you mixed up with along side the knife you are gluing up. This way you can check how it sets up by checking the residue adhesive. If you are using a one squirt type adhesive, squirt some on a scrap piece and let it sit.

To mix up goop, I use craft sticks (popscicle sticks) from Wal-Mart or one of the hobby stores and little plastic 'sampling cups' from Sams Wholesale. These little sample cups might hold just a couple of ounces of liquid. Little bitty dixie cups work well too. Make sure to get the kind with no wax.


I always use latext gloves as all epoxies are sensitizing meaning it is just a matter of time through multiple exposures that you will develop an allergy or possibly worse. Don't let this junk get on ya. It will kill you slowly if you let it.

[TexasJack]

I'm also working on a web site that I should be getting up and going soon. Would love to help out.

As for mixing glues, I keep the plastic covers that come on packages of glue, toys, tools, ...whatever. I just rip off the cardboard backing and toss the plastic in a bin. They're great for mixing small quantities of epoxy and they're free.

[DaveL]

Since this seems to be slowing down some, I would ask to be sure and post here where the results will be found. So many questions and so many answers cause only a little discomfort. I wonder how many of use will be changing adhesives after this.....

[tmickley]

Originally Posted by DaveL

Since this seems to be slowing down some, I would ask to be sure and post here where the results will be found. So many questions and so many answers cause only a little discomfort. I wonder how many of use will be changing adhesives after this.....

Steve had a 2 week trip somewhere and I'm waiting on some K&G epoxy to get started again. We'll 'revive' this thread when we get going again and publish a spreadsheet and conclusions/recomendations when it's done.