Is just using epoxy to glue down scales a bad idea?

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kaizo

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Oct 17, 2014
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I was just wondering as I would like to make a shirasaya like handle but people back in the day used rice pulp glue to stick the scales together and that seemed to hold itself together relatively well...

Do you think just using epoxy (which is a much stronger glue) to glue down scales is a bad idea (i.e. for aesthetic purposes leaving the pins out)?

Thanks for your help everyone! :)
 
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I think it's a bad idea. I tried it twice and both time one of the scales came off.
 
Sorry one more thing is there a rule of thumb for hidden pin lengths? Like the pin should only be half as deep into the scale etc...
 
I'm of the firm belief that there should always be some sort of mechanical means to keep the handle on the tang. That might be (preferably peened) pins, a Corby bolt, hidden pins, a threaded or soldered pommel on a hidden tang knife, etc.

I would much rather build a knife with only pins and no epoxy, than build one with only epoxy and no mechanical fastener.

kaizo said:
Sorry one more thing is there a rule of thumb for hidden pin lengths? Like the pin should only be half as deep into the scale etc...
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As deep as it can be without you grinding into it when you shape the scales :) But even a small stub of hidden pin going into the scale will help shear strength a lot and provide much more peace of mind.
 
Thanks very much I'll give that a go! :)

Probably will try 3~4mm stud for a 6mm scale just to be on the safe side first. (I'm putting pins away from the central axis because I'm making a sandwich handle and I need some pins to support the middle layer).
 
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I have tested unpinned scales with a sledgehammer and have to say if you can get them to budge you aren't doing something right with your glue-up.

That being said i always use some sort of pins from hidden 1/8" micarta to flared 3/8" tube.
 
james terrio said:
I would much rather build a knife with only pins and no epoxy, than build one with only epoxy and no mechanical fastener.
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I see a couple thousand mostly poorly cared for knives a year through sharpening at farmers' markets. Old stainless knives keep their integrity as long as the scales and fasteners don't break down, with or without adhesive. An awful lot of them seem to be made without adhesive.
Carbon steel blades, however, often have the scales forced away from the tang by rust, once the crack between the scales and tang allows water in.
As Terrio says, good fasteners delay that by a great deal.
 
Belt and suspenders... ;)

It's just not that difficult to employ both. "Saving" a few bucks or a little time by skipping either one is just plain dumb.
 
Some of my first knives were made as you suggest, but I didn't do it for long.
Really liked the sleek look of no pins, but had some failures.
One, however, I do see once a year when the lady brings it to me for a touchup- it was made with PC7 epoxy, binding bubinga to chainsaw chain damascus, using short pieces of 5/32 brass all thread for hidden pins. Unlike most of the other experiments, it just keeps together year by year...I expect her to bring it in in pieces one of these times...
Fasteners and G-flex.
 
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