Glue Wars - the battlefield is set

Status
Not open for further replies.
You know Roger, that's what I used to think. But now there is no question in my mind that for handle slabs it's E-120HP. Easier to use, better stuff. It's also a nice consistency - not too thick, not too thin.

However, now RW has me thinking. But I can't afford that stuff!

Steve
 
Geeze, this is all making me think I should get a dozen or so different glues/adhesives that are easy to find in NZ, the local Bunnings store has an entire wall of glues from $20 to $3 per 100mls of 2 part epoxys, and then theres the single part superglues, UHU, the Ados range of glues. etc... etc... Maybe after my tax rebate comes in I'll budget 50 bucks or so and try some of the entry level cheapies :P

I think I'll add bolting the metal to the engine of the garden digger or the lawnmower for a vibration test :)
 
Steve, when you get ready for your next test, I will pack up some samples for you to try. I think I heard that K+G was going to sell it in repacked smaller units for around $30-$40, not sure about that though.

Figure it this way though. A liter will last me for about 600 full size full tang fixed blades. So $0.50 per knife is not so bad. Cheaper than Devcon if you count what you end up wasting.
 
Steve, I doubt any bonding material would adhere sufficiently without some design feature added to aid. A stick tang is rather easy by virtue of construction. Simply slapping a couple dissimilar materials together and relying on an epoxy for lifetime is not going to prove reliable, I believe. I hold that some machanical or surface interlocking essential. In such case the argument expands to not just bonding ability but also strength of bonding material. The later is a reason I am a proponent of aggragating the bonding agent with a strong aggragate, such as gravel is used in concrete for that very reason.

RL
 
Thanks Steve for a very informative and fun test. I think the bottom line for me is that the epoxy I use is more a sealant then a way to attach handle scales. I always pins or use bolts.
Scott
 
The Hyper-Flex pipe-sealant is in the dishwasher for two days. It passed shock impact and toughness test, a strong man cannot take the bond apart, no matter how hard I try. The adhesive is not affected from dishwasher test also. I think it is the most suitable adhesive I found for bolsters and guards.

Mr. Steve,

I would love to see the results also for corian, horn, ivory, brass, copper etc. for the winner products. For example the Loctite Hysol is not so good for Corian, the Jb weld is not for wood. This makes me think, is to apply different adhesives for every different material on our blades more appropriate.
 
Sando said:
OK tracy your turn.

I hope this has given you some food for thought on your tests. I REALLY looking forward to a full report.

Steve
Click to expand...
still waiting on some material so I can do mine but I'm pretty sure I can't follow up with the drama you have managed to give a glue test. If that doesn't show up soon, I'll go with what I have. This has been my favorite thread for some time so I'm looking forward to it. Desperate Housewives should give you a call...:D:D:D
 
My whole life hinges on this thread on a daily basis! (just kidding Steve, I am enjoying every bit of it though) Can't wait to see what Tracy comes up with.
 
Thanks Steve for the effort and for sharing. This was great. I know there are alot of variables and such but, it's good to keep everyone thinking. Got me thinking.........uh oh!
:D
 
Great test! You discovered one thing most woodworkers know. Glue (adhesive) is stronger than wood. When you stress the joint, the wood breaks, not the glue.

But I agree with Razorback. The glue seals out moisture. Rivets hold the handle on. Filling a hole for a hidden tang with epoxy is for the birds. A mortised tang is much better. Even a burned in tang is OK, I think, so long as you seal out the moisture.

Happy testing!
 
Cool thread. Thanks, Steve.

One other variable that I would find interesting to introduce into the equation is the surface of the steel. When I use epoxy on my knife handles, I generally rough up the surface a bit before applying the adhesive. I've never done any tests to determine whether or not this helps, but have always just assumed that a few deep scratches will provide additional surface irregularities to which the adhesive can cling, thus improving the bond.

I wonder if something as simple as a few "#" shapes scratched into the surface with a scribe would make a difference...
 
Well, the first thing I'd like to say is "THANKS". Like everyone else on the board, I've been following this thread daily. I'm curious how many users are going to give up their favorite adhesive in light of the results. It's going to be tough to tear me away from my loyalties. They've never let me down.

Someone mentioned eliminating the dishwasher. Please dont! I'm sure it is one of the most common abuses our knives face. A little over three years back, I made a couple hundred steak knives for a high end restaurant. (A six month job to complete). The instructions were that they were never to face a dishwasher. That lasted about two weeks. Ever since, they have been through a commercial dishwasher several times per day. Last fall, I got 50 back for refinishing. There were chunks chipped out of the wood and even the pins from being tossed into bus trays. The sharp points and serrations were hard on ones they bumped up against. Not a single one had the glue give up though. The few that were bad enough that I had to replace the handle entirely, had to have the scales ground all the way off.

I don't think I'm switching - but I'm sure interested!

;)
 
rlinger said:
Simply slapping a couple dissimilar materials together and relying on an epoxy for lifetime is not going to prove reliable, I believe. I hold that some machanical or surface interlocking essential.
RL
Click to expand...

You're either confirming eveything I said or you refuse to read my posts.

I can't tell.

Steve
 
galadduin said:
The Hyper-Flex pipe-sealant is in the dishwasher for two days. It passed shock impact and toughness test, a strong man cannot take the bond apart, no matter how hard I try. The adhesive is not affected from dishwasher test also. I think it is the most suitable adhesive I found for bolsters and guards.

Mr. Steve,

I would love to see the results also for corian, horn, ivory, brass, copper etc. for the winner products. For example the Loctite Hysol is not so good for Corian, the Jb weld is not for wood. This makes me think, is to apply different adhesives for every different material on our blades more appropriate.
Click to expand...


Wow, that stuff sounds great! I'm gonna have to see where I can find it.

Steve
 
Rob! said:
Well, the first thing I'd like to say is "THANKS". Like everyone else on the board, I've been following this thread daily. I'm curious how many users are going to give up their favorite adhesive in light of the results. It's going to be tough to tear me away from my loyalties. They've never let me down.

Someone mentioned eliminating the dishwasher. Please dont! I'm sure it is one of the most common abuses our knives face. A little over three years back, I made a couple hundred steak knives for a high end restaurant. (A six month job to complete). The instructions were that they were never to face a dishwasher. That lasted about two weeks. Ever since, they have been through a commercial dishwasher several times per day. Last fall, I got 50 back for refinishing. There were chunks chipped out of the wood and even the pins from being tossed into bus trays. The sharp points and serrations were hard on ones they bumped up against. Not a single one had the glue give up though. The few that were bad enough that I had to replace the handle entirely, had to have the scales ground all the way off.

I don't think I'm switching - but I'm sure interested!

;)
Click to expand...


I've gotta know Rob! what did you use. That sounds better than any test I've ever seen.

Steve
 
Sando said:
I've gotta know Rob! what did you use. That sounds better than any test I've ever seen.

Steve
Click to expand...
The product is a slow cure epoxy from Industrial Formulators and it's called simply G2. It is specifically formulated for oily woods. FWIW, the steel was 440C and the finish under the handle was to 320 grit. Four pins - epoxied in with the same stuff and the wood was stabilized - by WSSI of course. The scales were sanded to 220 on the steel side. Clamping was the black and orange spring clamps available everywhere. The stuff is essentially clear and I clean up excess with a Q-tip and acetone while it's still wet.

I think the pins are important. While they aren't mechanical rivets, they do go a long way to mitigating shear stress.

By the way, the test was not on purpose - I was some pi**ed off!
 
My suggestion would be to repeat the test using the same glues, only this time prepare the samples to better simulate a knife handle, i.e. glue and pin the wood pieces to the steel with some 1/8" sections of nickle-silver brazing rod ...say, two pins per sample piece. No peening of the pins, just epoxy/glue on the pins (and in the pin holes), and grind flat.

Now you have mini-sections of knife handle. Test away.

Oh, and I don't recall if you did this on the first test, but the steel should be 'roughed up' somewhat with sandpaper in order to provide a better gripping surface. Then degrease the steel. No degreasing of the wood pieces, just clean them with a damp cloth first and let dry.
 
Summary

The test was not a success. My impact test was too violent. I wanted to know if the epoxy was still working after 'environment' testing. (I wasn't testing a construction method or impact testing on it's own.)

But I still learned a lot. Mostly about choosing the right epoxy for the task.

I'll try and pass on some hard information:

Gap Filling

If your construction method includes large gaps (over .010") you need to use an epoxy designed for that. For example:

* hidden tang knives with drilled centers
* slabs with epoxy pockets (be sure to use holes in the steel matched up with the pockets in the wood.)
* skeletonized tangs

When I saw how much most of the epoxies shrank and pulled away from the steel I realized how important it is to take that into consideration.

Epoxies for this purpose:

* Acraglas
* JB Weld

flat surface bonding

A smooth stainless steel surface is a bad idea. I wouldn't use any less than an 80 grit finish. Not one epoxy held well on the smooth surface I used.

I recommend this process for full tang, slab construction:

Finish the wood and the tang to has fine a grit as you like (220 or finer for the best appearance). Then using a contact wheel and and 80 grit belt, rough up the non-visable contact areas (that is to say: stay away from the edges). Don't go deeper than .005". Otherwise you need a gap-filling type epoxy.

Now bolt your slabs on (or pin and peen) and do NOT use clamps. The bolts are going to create a static pressure that is not released like when clamps are removed.

The winning adhesive for this application has to be E-120HP.


Natural Materials

I don't have much data in this regard, but I would not use something like E-120HP on bonds of dissimilar materials (like ivory to steel).

When the stabilized wood and E-120HP was boiled the wood cracked. The E-120HP simply would not move with the wood.

For that use Loctite Extreme is the choice.



Mechanical Bonds

It's been said several times by myself and others. mechanical bonds are essential. If you got nothing else from the test, I hope this point came out.

Steve
 
I think it would be useful to conduct such a test on a stick tang configuration.
 
Joss said:
I think it would be useful to conduct such a test on a stick tang configuration.
Click to expand...


Actually a test (or competition!) on full tang construction would be way cool, too.

How about a free for all? Everybody makes a knife-like object using what ever method, materials, 'glues' they want; send them all to the same place. Then we run them all thru the same tests.

Wow that would be killer fun!

Steve
 
Status
Not open for further replies.
Back
Top