Skeletonized handles

[jdm61]

I am making some prototype full tang knives and was wondering how some of you skeletonize or drill the tang to lighten it up? I only have a cheap HF type mini mill-drill and a big drill press. I am using CPM 3V and it will be HT'ed by someone else, but I am still wondering if lots of holes, etc are going to create stress risers even in an air/vacuum hardened steel.

 

[Will52100]

The way I do it, is to picture cut out areas and drill 1/8" or so holes at the corners. Then use a cut off wheel in a dremel to cut the sections out. I leave a cross section near the middle for a middle pin, but front and rear I take a big hunk of metal out. This added with tapering the tang makes for a very light and balanced knife provided you got the blade rite. This is for a knife that's getting scales, so as long as enough metal is left it doesn't have to be supper neat. If I was going to do a cord wrap or bare tang I'd do a bit different.

Oh, and for stainless blades I drill the holes, then heat treat, then use the cut off wheel to remove the sections to avoid stress risers. Come to think of it with stainless I don't grind the blade or taper the tang until after heat treat.

 

[james terrio]

Keep in mind that scales and bolts add significant weight. So when planning a skeltonized blade, you don't have to factor that in. Just finish-grind the blade and start poking holes till it feels/balances right. Of course it looks nicer if there's a pattern to the holes, not when it looks random like you blasted it with a shotgun Once you have a prototype balanced, if you plan on making several of the same model, waterjet is the way to go. Or use the original as a drilling template.

I drill and taper my tangs pretty heavily, then lightly countersink/deburr the holes. Never had a problem with stress cracks after HT.

 

[Stacy E. Apelt - Bladesmith]

I drill large holes on the drill press at each end, and then use a 1/4" side cutting bit on the mill to cut between the two holes. A little touch up with a file does the rest.

 

[mete]

Stress risers are caused by sharp corners. The radius in any hole should be generous. If you do a HT'd high tech steel then you have to ask an expert like Nathan to do it !! A thick full width, length ,and thickness will add lots of weight and you'll have a poorly balanced knife and the weight will do nothing for you. Just remember to think about screw and pin locations .

 

[james terrio]

Stress risers are caused by sharp corners.

Except when I need a hole for an 1/8" pin, all inside corners on my tang shoulders and holes within a full tang are 3/16" minimum, to avoid too tight of a corner. This may be overkill, I don't really know. But it's worked so far