Drilling A Hole Vs. Milling A Hole - Bit In Lathe Tailstock

[Charles Spencer]

Using a dog on larger drills to prevent rotation will stop the spinning in the Morse taper. It is also a good idea to check the drill tapers and tail stock socket for damage and the fit of the drill in the taper to see how good the fit is. A hardened Morse taper tool or bushing of good quality and in new condition can check the tapers using Permatex High Spot Blue for marking and scrapers for removing burs and high spots. It is a bit tedious and can take some time, but those tapers can be tested and repaired for solid seating and for concentricity with the quill. A Morse taper reamer can also be a good tool to use judiciously.

I have an SB 9C and a 9A. I often use a dog when drilling with a large diameter bit on the lathe.

My SB 9A was having some trouble holding on to a drill chuck. I had an MT2 reamer and that seemed to fix a lot of the problem.

 

[Wreck™Wreck]

Ive been doing the incremental increase because I'd read about that method before I read about the straight plunge with the mill bit.

What do other SB9 or any other owners of small lathes do ?

I have never used a Southbend small lathe but I suspect that it has the power to drive a 12MM drill through many different materials in back gear, try it you may be surprised at the outcome. Keep the feed up and a steady uniform chip forming at all times if possible, this is what twist drills are designed for. Do not expect an accurate diameter, ream or bore after drilling, drills are roughing tools.

 

[4GSR]

...........What do other SB9 or any other owners of small lathes do ?

The time or two I've done it in my 9" SBL, I do it just like you have done. I've pushed much larger endmills into a hole to create a flat bottom hole for what ever the reason was.
I will say, the endmill tends to "grab" and when it does, it will pop the 2 MT from the tailstock. A driving dog won't even help you here. As others have said, keep a smooth even feed, not too fast, not too slow, and use lots of your favorite cutting oil in the drilling operation.