I'm new to blade making, and I'm at the point where I've cut the threads on a dirk tang and, now, need to drill and tap the nut of the pommel cap. I've annealed some tool steel I had laying around, and cut some sections using a band saw. When I use the drill press to drill the hole the drill bits dull pretty quick. I use oil and try not to burn up the bits with too much pressure- but, they drill to a point, then stop cutting. When I get a hole deep enough to tap, the tap cuts okay in 1/4" back and forth turning initially, but, at about 3/8 " to 1/2" deep, the resistance becomes so great that the tap breaks off in the hole. Help! I knew I shoulda taken those shop classes in high school! Suggestions anybody?

I think the cleanest way to do this is to get a nut that will fit the threads on your tang, and silver braze it to your butt cap. you will have to counterbore the handle material to accomodate the width of the nut. Fit up all the parts (you might have to bend the tang a bit to get the butt cap to thread on so it's flush with the handle), and when you've got it right, take it apart, fill the spaces with epoxy, and put it all back together. Let us know how it works out!

hielander,
Don made an excellent suggestion.Which is the norm.

If you want to keep cutting the treads yourself may I suggest that you get a bottoming tap or take the one you have and slowly grind the point back some.Keep some of the taper(enough to start the tap)and this will help considerably.Also make sure you are using the right drill bit size,a fraction or so too small may be the reason for the resistance.

Hope this helps you out.

Mike K

Yea Don and Mike are both right. One other problem might be the type of tool steel because some of them are very poor in machinability. One option is to go to mild steel or alot of times I will drill one or two sizes bigger than the tap calls for. So you end up with 70% threads instead of 100% and if you epoxy it there isnt much difference because it usually isnt tightened tight enough to worry about stripping them.

Right on target about the taps needed. Getting a full thread to the bottom of a blind hole strictly speaking requires a three taps, the taper, plug and bottom tap; although not many folks fool with this it seems. Otherwise You can A) simply accept that tang will not bottom out in hole(think of it as shortening the tang, or making the hole deeper). or B)file a taper on the tang so that the tang hits bottom while engaging what threads there are. Remember you only need three or four full threads to get near full strength. You may not be wanting to use epoxy to assemble if you want the knife to be dis-mountable in the future like a sword. In which case I recommend good old non-hardening gasket goo like you use for automotive parts. Believe me it wont come off until your ready for it to.

Thanks for all the suggestions, guys! I'm going to try the mild steel, get the different types of taps, try a slightly larger drill diameter. I think I may use rifle bedding stuff when I do the final assembly on this dirk (I didn't achieve as close a fit in the handle as I would have liked). Thanks, again- very, very helpful!