Where to get a counterbore?

Leu Custom

Leu Custom

Joined
Jun 2, 2007
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Does anyone know where I can get a counterbore that would go from 1/4" to 1/2" ? And any other sizes you can think of? Thanks in advance!
 
try MSC or J&L Industrial supply. They have everything you could think of. I don't know the links, but do a search on google for each of them and they will come up.:thumbup:
 
They don't seem to have what i'm looking for !

Looking for something that looks like this photo found on Daniel Koster's website

koster.jpg


Thanks! I want the whole step that the counterbore produces like in the photo of the scales he has drilled.
 
If you want to drill both holes at once as with the bit in the foto, then search for "step drill" at places like MSC. If you want to drill the 1/4" hole first and drill in the step in a second operation, then search for "piloted counterbore".
 
And if you want to use Corby bolts, the step drills and counterbore bits can be ordered from the knife supply company as an exact fit for the bolt size you choose. They all carry them.
Stacy
 
Leu, you could just make one youself. Do you have a lathe ? A dremel/foredom grinder ? Set it up like an improvised tool post grinder. Chuck up a 1/2" drill in your lathe and use your grinder to cut your step. I can make a custom CB in about 15 minutes if need be. You could even do it in a drill press if that's all you have. They work excellent for handle materials. For a CB that works in steel you will want to be a bit more fussy about cutter relief, geometry etc., but it still can be done quite easily.
 
The counterbore in the pic above only drills the larger hole. The small shaft is for holding it in position in a pre-drilled hole. This is for handle material only...not for steel.

This one in particular belongs to Tom Krein. I think he had it special-machined? I'll find out for sure.

You can get something similar at www.mcmastercarr.com ...but to get the exact size you want, you'll need counterbore with interchangeable pilot

3102A19 is the PN for the 1/2" counterbore
3103A2 is the 1/4" pilot

Dan
 
I use improvised c'bores similar to the one shown all the time at work. It is a modified step drill. This one has the point ground off to prevent it from drilling it's own hole or to square up the bottom of the pre-drilled pilot hole. Lacking the in-house ability and expertise to make them ourselves, we had them made by a local vendor called Mary's grinding here in the St.Louis area. I think the cost was about $20 ea. in onesy-twosey quanities. Check some of your local machineshop suppliers and tool grinders, I'm sure they'll be happy to hook you up for a reasonable fee.
 
Now that you show a pic, it looks like a modified drill. Like others have said, we make them all the time here at work. You can do it by hand, but you really have to know what you are doing or you\'ll mess up the center. Its hard to grind/sharpen a drill by hand, and still have it cut with good concentricity. More often than not, one side ends up different than the other and the drill will wobble yielding an oversize hole. The way we do it is to take a drill and put it in a spin jig, then we just spin the OD down in a small dry surface ginder.

I can\'t tell if the one in the pic has a point, but it looks more like it is flat bottomed. This would be for, as others have said, just as a pilot. If you can\'t find anything, email me and I might be able to help you find what you\'re looking for. If you have a machine shop near by, that would be your best bet. Most of the older machinist know how to modify tools well, because they didn\'t have the luxury of all the choices of tools we have today. We have a guy here at work that\'s 70 years old, and that guy could make a stick cut hardened steel if he had something to sharpen it with...lol.
 
Now that you show a pic, it looks like a modified drill. Like others have said, we make them all the time here at work. You can do it by hand, but you really have to know what you are doing or you\'ll mess up the center. Its hard to grind/sharpen a drill by hand, and still have it cut with good concentricity. More often than not, one side ends up different than the other and the drill will wobble yielding an oversize hole. The way we do it is to take a drill and put it in a spin jig, then we just spin the OD down in a small dry surface ginder.

I can\'t tell if the one in the pic has a point, but it looks more like it is flat bottomed. This would be for, as others have said, just as a pilot. If you can\'t find anything, email me and I might be able to help you find what you\'re looking for. If you have a machine shop near by, that would be your best bet. Most of the older machinist know how to modify tools well, because they didn\'t have the luxury of all the choices of tools we have today. We have a guy here at work that\'s 70 years old, and that guy could make a stick cut hardened steel if he had something to sharpen it with...lol.
 
TKS, Midwest knifemakers supply, Jantz and probably E-bay.

I saw a whole set on E-bay for around 30 bucks. (piloted)
 
Leu Custom said:
They don't seem to have what i'm looking for !

Looking for something that looks like this photo found on Daniel Koster's website

koster.jpg


Thanks! I want the whole step that the counterbore produces like in the photo of the scales he has drilled.
Click to expand...

That's a step drill not a counter bore. A counterbore will be better and cheaper. A counterbore gives you a square flat bottomed shoulder in your hole. it will cut clean every time.
 
it would be nice if a Std. set for folder screws and corbys was out there at a good price
1-72 2-56 4-40 and say 3 sizes of corbys
 
might be the angle in the pic...but the above counterbore does indeed leave a square bottom.

this is a better pic...but not perfect:

HandleTutorial-CounterboreSet.jpg




Like I said before, this was sent out and machined down to size. If you wanted something specific for corby bolts, you can get a counterbore from Pops Knife Supplies: http://www.popsknifesupplies.com/bore.html

But I had a hard time finding one that would go from 1/4" to 1/2".


Maybe mscdirect has something?
 
damn! didn't think this thread would get this many responses! Thanks guys! i'm trying to use the 1/4" pilot with the 1/2" counterbore on a simple hex bolt to screw the handle together. may look pretty ugly to most of you, but something someone wanted on their funky knife.
 
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