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I'd reverse the operation. Drill and tap the hole for the set-screw in a block. Clamp the block to the table, while aligning the set-screw hole under the chuck. Drill a hole the same size as the rod and lock the rod in place with the set-screw and swap the bit. Alternatively, you can skip the set-screw all together and just make a thin saw kerf that can be clamped closed around the rod.
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I never tried this, but it works perfectly in my mind.
Take two small blocks of wood and sandwich the bit between the blocks and clamp it in a drill press vise. Tighten the vise. The wood should conform to the drill bit shape. I would use a hardwood like oak or maple. I think you can get enough friction to keep the piece from spinning, but it is not 100% certain. Some sandpaper in the sandwich might increase the rotational resistance.
In any event, it will be very cheap to try out. Getting the bit to stand perfectly straight might be time-consuming.
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I wanted to rotate the workpiece and not the cutting tool.
What did work was a big piece of pine with screws in the side holding both a piece of hardwood and steel plate to grip the bit. 4 screws and a lot of pressure, and it still pushed the bit. It's just so small and so smooth.
I added PSA sandpaper to both the steel and hardwood, as well as a screw below the bit so it couldn't be pushed, and that did the trick for 20 holes, or so. All I needed.
I've got a larger chuck on the way for an unrelated project, so if I ever have to do this again I'll bet that will be the better option.
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(07-28-2021, 09:33 PM)Robin Dobbie Wrote: Whelp, I'm here for my yearly question.
So I need to put a 3/32 hole in the end of a steel rod.
good job for a metal lathe
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07-30-2021, 07:22 PM
(This post was last modified: 07-30-2021, 07:23 PM by museumguy.)
I no longer build museums but don't want to change my name. My new job is a lot less stressful. Life is much better.
Garry
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This type vice may be more than you want to spend but it will hold your small bit and then you can hold it in a larger vice that you can clamp down.
https://www.amazon.com/Toolmakers-Vice-2...39&sr=8-35
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(07-28-2021, 09:33 PM)Robin Dobbie Wrote: Whelp, I'm here for my yearly question.
So I need to put a 3/32 hole in the end of a steel rod. The rod's chucked up in the drill press, I need to come down with it on a bit. Found an old drill, removed the chuck, and it doesn't hold the bit well enough.
Found a piece of hardwood and drilled a 3/32 hole through, and a 1/4-20 perpendicular to that hole so I could have a bolt hold the bit. It actually achieved a hole in the rod, but it did move a smidge.
My next tricks were going to be grind a flat on the bit, try again, or put some 80-grit PSA sandpaper on a couple pieces of hard wood and clamp/screw them together on the bit.
a little late now, but there's a set of 5 1/4-28 shank collets for 3/32 bit on ebay
https://www.ebay.com/itm/133650255589?ch...x8QAvD_BwE
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Use your lathe and put a chuck in the tail stock. Easy.