drill bits

[Scott the knife]

Who can recomend an affordable($50) drill index.I have a few elcheapos in the shop,but wnt to get one just for knifemaking. Also do i need to ream out a hole after drilling? Example I am going to put a 1/4 thong hole in my first knife.Do I just drill a1/4 hole and push an epoxied pin in, or is there some trick-o-th trade to doing it?

 

[rlinger]

What I found cost effective for me was to buy a 115 piece (I think) set of titanium nitrite bits from Enco ( www.use-enco.com ). They don't cost much because its all China stuff. Then; here is my trick, when I wear or break a few of the bits I replace them with expensive cobalt bits on my next order. This way I only put out for the high dollar stuff a little at a time. Pretty soon the sizes you use most often will be the good stuff and it is not to hard to buy an extra or two in the sizes most used.

In drilling 1/4 holes in steel tangs I start with a small bit then go to a medium then end with the 1/4 inch bit, always keeping coolant - cutting oil on the work. Starting with the 1/4 inch bit will chatter and cause much more wear too quickly. Drilling steel requires patience and I go slow and try to keep the work cool.

I have been scoring tang pins to give them better bonding. I have not reamed any tang holes.

Roger

 

[Bill Siegle]

I think your best bet is to figure out which drill sizes you need and go to an industrial supply house and buy what you need. I always found myself using just a few bits out of a set but having to pay for a bunch of unused bits. Not to mention the fact that the sets are generally of lesser quality(unless you go real expensive). For example I am down to using #19,#11,1/4in,#30, and 3/16ths drills. Add to that list a countersink and those are my standards. I keep at least 3 of each on hand and buy either cobalt or TIN coated bits. As to reaming a lanyard hole I don't do it myself. If you are adding tubing for a lined hole a rougher surface will actually help hold the liner and epoxy in place. Be sure to roughen the outside of the liner material with a file too. Have fun.

 

[Mike Hull]

You want to go ever so slightly oversize, especially on handle material, as it shrinks back after the bit has passed through. After drilling the tang holes, break the edged of the drilled holes with a chamfering reamer, or countersink, single flute/blade works best.
Here are the common sizes of bits.
1/16" = #52
3/32" = #41
1/8" = #30
5/32" = #21
3/16" = #10 Thong hole tubing
1/4" = "F" Thong hole tubing
The reason for chamfering the tang holes is to reduce 90degree inside corners, which helps reduce the formation of stress risers.
Hope this helps a little.

 

[Andrew McLurkin]

I agree with Bill. Buy good quality drills in the sizes you are going to use the most. I buy them in package quantity, and sharpen the bigger ones with a Drill Doctor and throw out the small sizes - under 3/64". That way I'm buying mostly the less expensive small bits. Dull bits don't cut steel at all.

I'd measure the outside diameter of your thong hole just to make sure its not over 1/4". Under is fine. If its over you can spin it down some with a drill and sand paper.

 

[C L Wilkins]

I use a 6.4 mm drill bit for 1/4 inch holes. It is .252 inch whereas a size F is .257. You can get metric size drill bits at any industrial supply house such as WW Grainger, Wholesale Tool, MSC Industrial, etc. I also use a 4mm for some other size hole, 1/8 or 5/32, I can't remember off hand.

C Wilkins