Drill a plug

[donkjr (Don Kleinschnitz Jr.)]

I thought it would be fun to do something different.

How do you drill a 1/4 inch hole directly through the center of a common rubber stopper?
I need this for a woodturning tool I am making, thus the reason it is posted here.

The challenge:

…describe the fabrication method and tools needed to drill a near-perfectly centered and formed 1/4" hole through a rubber plug whose large end is 1" in diameter and the small end is 7/8" in diameter.

Full disclosure I already accomplished this but wondered how many ways this can be done…

[NedMan (Ned Hill)]

As a chemist I’ve used specially made hole cutters to cut holes in rubber stoppers.

https://www.ebay.com/i/184329009191

For exact centering I guess I could laser cut a washer like jig to center the hole cutter? Hard to get a perfecting aligned hole with a plug cutter by hand though.

Make a hole cutter from some tubing and mount everything in your lathe maybe?

[funinthefalls (Anthony Bolgar)]

Laser cut it? How thick is the rubber?

[mcdanlj (Michael K Johnson)]

Lathe is the most obvious to me, but I’ve done something similar by 3d-printing a jig to align the part and the bit.

[donkjr (Don Kleinschnitz Jr.)]

The top is 1" and the bottom is 7/8".

[donkjr (Don Kleinschnitz Jr.)]

I learned the following:

• A twist drill will not drill cleanly, very grabby.
• A Forstner bit cuts extremely well.
• If any part of the wall of the plug is unsupported it will distort and not drill straight.

My solution after a few attempts at other methods. On the lathe with a tapered hole in a jam chuck drilled with a Forstner bit in a jacobs chuck.

[NedMan (Ned Hill)]

Nice solution