Handle questions...

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Mike Davis

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I am working on the handle for my suji and am having troubles with the copper spacers heating up and breaking the epoxy bonds....This handle has a lot of copper spacers in it. I dont want to get it wet to keep it cool, but if i just do a little and let it cool...it will take me a month to get it done....Any ideas? Maybe lose the copper and go with a copper fiber material? I am about to pull my hair out over this...

Thanks
Mike
 
I feel your pain Mike. I've had them come apart even using JB Weld. I'll be sitting back waiting to hear an answer for this one.
 
Yup, copper is uber difficult to use. The only thing I have found to work is gorilla glue. But then you have to deal with the expansion issue. If you do use it, use just a very thin layer and compress the heck out it.
 
The stress caused by using metal spacers has cost me a few years of my life expectancy. If there is an easy answer, I would also love to hear it. Handles with metal pieces cost me about twice the time that other handles do (and I charge about 20% more for them...). I have not found anything better than going slow and using the best epoxy you can find. Going slow is also important because it not only affects the epoxy bond, but some woods or especially horn burn very easily and you get burn lines in the materials that connect to the spacers. Dave told me once to 'use belts and sanding materials like they don't cost anything', and that has increased my cost but also made work much easier, fresh belts make a huge difference. And I do as much as I can to grind the metal pieces down before I glue things together to minimize the time I heat up the metal pieces, and I do as muchas I can on coarse belts before I go to finer grits. And while I can sand handles that only consst of stabilized wood to 800 grit on the belt, with metal pieces go over to hand sanding at 400 grit at the latest. For epoxy, I tried about a dozen different ones, and the two that seemed to take heat better than others are the K&G house brand and especially Brownell's acra glass http://www.brownells.com/.aspx/pid=1033/Product/ACRAGLAS-reg- - just don't use the gel! West Systems epoxy is also o.k. but you have to buy a lot and it's very pricey. At this time, I use acra glass for 90% of all epoxy work I do. It does set slowly but that's fine with me in most cases.

Just to check - is this a wa handle or a Western one? For wa handles, the only way to work them from all the experimenting I did (other than the more traditional method that Marko uses) is to insert a soft wood dowel that connects the pieces from the inside. More work drilling and more work lining things up, but it gives additional stability from the inside and keeps the handles from falling apart. When I started out, I had handles that I re-glued 6-8 times because the kept falling apart from the heat on the sander. With using acra glass and inside dowels, I have not had a problem, yet. <knocks on wood>

Hope that helps a bit.

Stefan
 
The handle i am doing is a "Frame handle" like on a take down bowie. The spine and main spacers are made of damascus, with copper spacers on both sides of them, the ferrule and buttcap are african blackwood and the scales are made of musk ox horn. I need to order some acra glas, been meaning to. At this point i am just trying to get the pieces glued together to shape them, but it is being a pita. I don't want to generate too much heat and warp or crack the musk ox horn, that is why i considered switching to a fiber spacer material. The spine has a tab that interlocks into the back assembly and the spine is cut to where the tang slides in for a tight fit. Here is a really rough pic of a mock up using the materials.
2011-10-24_01-23-33_445.jpg
 
Mike, what I've learned to use super glue. For whatever reason it holds up to heat better than any epoxy I've used. The biggest draw back to this is its inability to resist impact or shearing forces. It may be more work than you want to do, but super glue everything up, use no grit larger than 80 to shape your handle, get it within 1 millimeter of its final size, mark your handle with a permanent marker, take it apart, re-glue it using epoxy (after cleaning) and hand sand it to final shape. Yes, this seems like more work, but in the long run it saves you from breaking down due to a stress induced heart attack or aneurysm. For handles that are not laminated, you can use the mortise and tenon joint method either by turning a tenon on a lathe (you can get a small lathe attachment for your drill press) or my carefully hand shaping à la Marko.

*When you use superglue, make sure to use the thin version (thin, medium and thick are available). Don't slather it on, use it as you would spot weld.
 
I would normally say mortise and tenon construction, but using scales for the main body of the handle would require some extra creativity to keep the bond intact. Maybe internal pins?

M
 
Also, if price isn't an issue, you may want to try Resbond 940HT, it is rated for continued use at 2800 F.
 
Awesome, thanks guys. The handle will have 10 hidden pins and 2 full pins holding it together in the long run but only have 4 in it so far. Will try the superglue idea tonight and see if I can get it rough shaped that way.

Thanks again
Mike
 
How are you getting the thin copper sheets off when superglued to take it apart again?
 
I've had no issue taking them out using a small screw driver-like-tool that I made. Also, acetone will dissolve the glue if prying will not work. The hardest thing is learning to be patient and having a light touch. Remember, you're only using small "dots" of glue to hold them in place while you grind, if you place those dots toward the outer edges, then you're not left with much at the end. I tend to glue only the corners to make is much simpler.
 
May not be an acceptable answer, But Ive had to file handles before due to heat issues. Its suprising how fast a 10" bastard file will shape a handle. Not nearly as fast as a grinder, but an option.

God Bless
Mike
 
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