Do you really need the pins?

A

averageguy

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I was just reminded that Anza uses only epoxy to secure slabs to the tang. Given my limited experience it seems epoxy is all you really need. The stregnth of modern epoxies is measured in tons. Surely this stuff is strong enough to secure a couple ounces of material to a tang. I imagine a number of hiden tang designs rely only on epoxy to secure the handle. Your thoughts please.
 
My guess is that modern day epoxy is plenty strong enough..... unless you work around strong chemicals. Certain chemicals tend to eat glue for breakfast.

Personally, I'll take epoxy. It looks much nicer. I have a Buck 110 with a stag handle. No pins. I haven't had any durability issues so far.
 
I read that you can drill a couple of holes halfway through on the inside (where the holse will remain hidden). When you epoxy the slabs on, the epoxy will ooze into the indentations you made in the handle material, and it will form hidden "epoxy nails" that make the bond stronger.

Chang
 
My vote would be for pins, hidden, small, large or fancy. A member in the knife club that I belong to had a very beautiful custom made dagger. Two problems with it, the ivory scales with ebony inlay had come completly free from the tang and the pigment that was present from the padding that lined the knife case had bled into the ivory where the adhesive was present. Epoxy was the only adhesive attaching the scales. Now that might have been only bad epoxy, but wow does ivory look bad with red color in it. I think you have to look at the material that you are attaching and think about any oils or chemicals which might effect you adhesive in the long term.

Jeff
 
While epoxy has holding strength rated in tons it is generally susceptable to bond breakage due to shear stresses. The pins help prevent movement in shear situations thus preventing failure due to shear stress.

Careful measuring can allow the use of hidden pins but for the most part the market accepts and expects pins so we allow the pins to show.

Epoxy to epoxy bond also known as epoxy pins should be used whenever possible for extra strength.

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george
www.tichbourneknives.com
sales@tichbourneknives.com


 
To add to what George said, after a few years of heat/cold/heat/cold plus stress/stress/stress/stress... the epoxy bond weakens. Utilizing pins and other mechanical methods, along with the chemical one (epoxy) is your BEST bet for a super tough handle.

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"Come What May..."
 
i've been known to make a few knives here and there. i usually use files instead of buying stock, and after rinding most of the file teeth down to the point where they're visible but not feel-able, i affix slabs to these handles with JB Weld epoxy. i've never had a problem, even with the tough use that i've put my personal knife through.
peace.
aleX.

------------------
"i flip you... i flip you for real..."

"come and get one in the yarbles, if you've got any yarbles."
 
If you want me to buy it you better put pins in it. Epoxy tend to weaken from vibration, temperature, and chemical interaction. Its a good way to bed down the tang and handle, but you still need a good mechanical attachment.
 
I agree PINS
I use hidden, if I don't want any to show and I also go over board to be safe,
With bolsters, guards or what have you, I biscuit the ends, even with tapers (or called Dovetails)and fill with Epoxy

and I think the 30 min opoxy is better than the 5 min.stuff, so not all is the same.

...Dan...<A HREF="http://www.kynd.com/~graydg/kniveslist4.html">Gray Knives</A>


[This message has been edited by Graymaker (edited 06-27-2001).]

[This message has been edited by Graymaker (edited 06-27-2001).]
 
Pins for me. Epoxy may be rated in tons but it is not a flexible bond. Impact, twisting and bending can cause it to let go, and it does it all at once.
Since pins go all the way through the tang or liners, they cause any stress to be exerted on both the tang and the scale and from the same direction.
Think about it this way, you've got the blade of a knife stuck in something and your twisting the handle clockwise. With out pins, the brunt of the torque goes against the scales lifting the one on the left and pushing down on the right.The tang isn't stressed the same way, the epoxy bond has to flex and the scales pop off.
With pins.The scales and tang stay along the same plane anywhere that pins go through.The epoxy isn't flexed and the scales don't fall off.
Its less of a facter in folding knives because bolsters and other tricks can be used. And Epoxy glues have gotten good enough that they may work on theri own most of the time. But I would rather have pins along with it.
Also, remember that with only epoxy, when it fails the scales fall off. With propery peened pins, they'll probably stay on forever.

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I may not be the sharpest knife in the drawer... but I've got the sharpest knife in the room.
 
right, but think of this:
"j.b. weld" brand cold weld epoxy has been known to hold cracked engine blocks together (the big honkin' metal chunks of car engines, inside which the fuel is combusted and the pistons move). how's that for a stress test? adequate? i think so.
wink.gif

peace.
aleX.

------------------
"i flip you... i flip you for real..."

"come and get one in the yarbles, if you've got any yarbles."
 
I had a knife that the wood scales were held on with epoxy only. The wood naturally contracts and expands with temperature and humidity changes. One day I noticed a little gap. I pulled with my fingernail and the scale popped off! Same thing on the other side. I ended up sending it to Dr. Steve for repair. He ended up using two pins and epoxy too. Now it is perfect. In my limited experience, pins are neccessary.

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Always remember - you are unique, just like everyone else.
 
Alex,

You may be right. Unfortunately, as a consumer I would feel more comfortable with pins. The weld may work well on like surfaces, but we don't know what will happen when you use it to attach the metal frame to a micarta or organic scale. The wood/bone/stag/rubber scale may delaminate under that kind of stress, or perhaps metal corrosion under the weld will cause it to fail.

Also, I would suspect that the amount of flex, and the variation in the direction of stress is far greater on a knife handle than on an engine block. We just don't know.

There are makers that attach their handles with epoxy. Some have worked well but others have had serious issues. Recently, I was given an old Paragon Parabow that had been kept in storage for a couple of years. I opened the blade a couple of times to wipe the metal surfaces down with a little baby oil and one of the rubber scales came off in my hand. Poor workmanship and temperature variations during storage probably allowed the rubber to flex and break the bond.


n2s

 
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