Counterbore bits really necessary???

[nate d.]

OK Do i have to use a counter bore bit to provide a recess to lower fillisterhead or socket head torx screws in my handles or in the bolsters??? I would rather use a 135 degree drill bit and be done with it. I don't think i'd do it with a 118degree point put the 135 is what i'm leanin to. Just askin' before i go tryin' it so maybe i don't duplicate a mistake already made. i keep tellin' my self theres not a stupid question , when i ask questions like this. :confused:

[Belstain]

I've never used one of those.
I just use a drill bit the same size as the head of the screw.

[Osprey Guy]

Your 135 degree drill will work just fine with either of those screws.

Just drill your clearance hole for the screw, then while the chuck is still in postion, come back with the larger drill bit and do your countersink slightly larger than the screw head (the amount of clearance around the screw head is a matter of personal preference). Drill the countersink a little at a time, checking your depth by dropping your screw in the hole (I use the magnetic end of a scribe to easily lift the screws back out of the hole). If your scales or bolsters are contoured you'll have to sight-fit your countersink in similar fashion for each of the holes. If the scales are perfectly flat you can just set (or make note of) the drill press depth and repeat for each hole.

I hope that answers your question.

BTW- The simplest way is to get a stepdrill for whichever size and type screw you're using. Knifekits.com sells them for as small as 0-80's...I've purchased several from them. It makes it so easy to drill your screw holes perfectly in just one step. If you're drilling holes of this type frequently, I think they are well worth the expense. You'll find them listed there under "Knifemaking tools"
KnifeKits.com


Dennis Greenbaum

Yeah Baby!

[Ray Rogers]

I agree with the others that regular drill will do the job just fine. On my drill press I have added a dial indicator so that I can tell precisely how deep I am drilling a hole. That way, I can measure the head of a screw with my calipers and then dill to that depth. After that, if more identical holes are needed just lock the quill depth like Dennis said.

On occasions where the part receiving the hole is not much thicker than the head of the screw it may be desirable to have a flat bottomed hole. This can be accomplished by using a ream with the tip ground nearly flat to cut out most of the conical hole left by the 135 degree drill. Follow that with a clearance sized drill for the screw body and all of the conical shape will be gone.......

[rhrocker]

That's a great tip ray! I think I'll rig up a dial-indicator on my drill press. I've been "eyeballing" it, and it's not that accurate. Post a photo of your set-up if it's not to much trouble. If it is, I can visualize what you did.

[Ray Rogers]

Putting dial indicators on drill presses and mills and even on lathes is a very common practice. As always, I chose to do it in the absolutely simplest, fastest and cheapest way I could dream up:



What you see is simply a 1" wide strip of heavy sheet metal that was split down the middle for its whole length except for the last 3". The two 'legs' thus formed were twisted 90 degrees in opposite directions, spread apart, and wrapped around the quill of my drill press. A bolt, seen on the right side of the picture, secures the strip.

On the left is a common dial indicator and magnetic stand, available almost anywhere for $20 or less. This makes it easy to remove the dial if it is in the way and easy to adjust its position when in use.

This arrangement probably isn't accurate to the last micron but it is more than good enough for anything any of us will ever need to do.

On a different subject, notice the steps cut into the thick brass jaws on my vise. They are the reason I don't need to use parallels with this vise........

[R. D. Finch]

Ray

Thanks for posting the picture of your set up. I can now set one up.

[nate d.]

thank you all gentlemen for the replies, and i'm glad i didn't get the counterbores now in my MSC order!!!!!!! Thanks again. Now i feel more comfortable with that aspect of it.

[rhrocker]

Thanks Ray!