New knife maker, problems with multi layer handle.

A

armstrong

Joined
Sep 25, 2015
Messages
9
Hey everyone,

I just started learning and trying my hand at knife making. I'm new to this but do a lot of wood and metal work. I ended up with some end cut pieces of maple and walnut from a different project and decided to glue them up and make a knife handle. I used 3 pieces of walnut with two pieces of maple and thin brass strips as spacers in between. I rough sanded the brass for good adhesion and glued everything up with devcon 2 ton epoxy. After gluing I clamped the piece very tight and let cure for 24 hrs. Once set i through it on the belt sander to shape into a block. Problem is, as I sand and the wood and brass heat up the pieces just come apart. I have glued this up 3 times now, sanding the brass a little rougher and even making some small holes through it. but each time it separates while sanding. I know people make and sand handles like this so I know I'm doing something stupid.

I'm sure someone can point out what I'm getting wrong. Thanks in advance for any help!
 
Red flag #1 is getting the brass liners hot, even a little, and breaking the glue bond. Get it too hot and it's going to break most any adhesive bond.

Red flag #2 is clamping. Don't clamp so tight you squeeze all the epoxy out.

Red flag #3 is the devcon epoxy. There are probably better epoxies to use for that application.

Surface prep is everything, sounds like you might have that under control. Proper mixing of the epoxy goes a long way.

Don't get it hot. Even warm to the touch is probably taking a chance.
 
Thanks guys. I'll research a better epoxy and toss the devcon. I also didn't realize one could clamp too tight, but that makes sense. I had a feeling it was something to do with the heat in the brass. I've glued many wood blocks straight together that I've shaped on the belt sander and never had a problem.
 
Better place to ask these question is in the Shop Talk section under General Knifemakers Questions
 
I agree with some of John's thoughts. Main thing I think is clamping too tightly. When you do this you squeeze out all the epoxy. Also you can try a few holes in the spacers in the middle, just make sure they are in a location that they wont show once the handle is shaped. Other epoxies are better but a lot of makers, for a lot of years, have used devcon or whatever the local hardware store had. Any epoxy will fail if you get it too warm. Fresh belts and light pressure.
 
Walter Sorrels has a couple of really good epoxy videos that may be worth a look. I used his acetone and scotch brite advice and it works for me.[youtube]MTYN25w3XJw[/youtube]
 
Last edited:
I've used Devcon before and never had a problem. Its all in the prep work. I sand each layer with 220 Grit and then clean thoroughly with acetone.
Use 2 or 3 spring clamps is more than enough pressure for adhesion. Don't use c-clamps. As said before you will squeeze out all of the epoxy.

Another possibility is your epoxy could have gone bad. Believe it or not, it can happen.
Good luck!
 
I have been having the same problems with my first forays into layered handles... Some things are just learned the hard way, like just how heat sensitive epoxy is, or how frustratingly conductive copper is on belts...

i am going to switch to the loctite speedbond for it's higher temperature resistance next time

I found and old Simonds red tang 'big hoof' farrier's rasp, and is quickly becoming one of my favorite hand tools for rough shaping my handles
 
Use 100 grit lightly to rough up your surfaces and then wipe with acetone. Use g-flex epoxy or Loctite heavy duty and just put a small weight on the scale pieces to hold them or use some light spring clamps. You may also try k@G ( Knife and Gun) brand epoxy and use their black powdered pigment. This is a 24 hour epoxy that holds wood well. All of these3 have worked well for me. Drill a few extra 1/4 inch holes in your tang and it will hold much better. Good luck. Larry Lehman

wWf18SAl.jpg
 
Last edited:
Thanks everyone, all excellent advice. Like Pancake House said, there's a lot of learning the hard way which is all part of the process. In my case it was the heat and clamp tightness. I was approaching this more like a wood glue-up which typically works better when the clamps are very, very snug. Once I backed off the pressure and avoided my tendency to stay on the belt for long periods of time (which creates enough heat to give a second degree burn to the thumb!) the pieces stayed together. Once I have this thing done I'll post a photo. I'm just finishing my first ever knife and will post that as well to get some feedback from everyone.

Thanks again for all of the advice, it really helped!
 
If you can't or don't want to avoid heat during finishing, and you can live with a gray epoxy, good ol' JB Weld is a lot more forgiving of heat when it's cured...still will delaminate if it gets too hot, just not quite as fast. It's a very durable epoxy for the job.
 
I've used JB on metal and it is very strong, never tried it on wood though. Seems like it would leave a bit of a dull gray line on a layered handle but I might give it a test. I don't mind hand finishing the wood to shape, it's the brass in between and the pommel that wear ya out. I rough cut the pommel from a small bar of brass and am hand sanding it down to shape to avoid it flying across the shop off the belt sander/launcher.
 
You must log in or register to reply here.
Back
Top