Drilling on Lathe Help?

[JohnsonMBrandon]

Can someone provide me with some good information on drilling on the lathe.....I am having issues when I try to do this. I've always drilled everything out on the drill press, but would like things to be a little more precise at times.

I chuck up my blank, and have my drill chuck in the tail end. When I try to crank the tail end into the chuck it will catch and almost unsrew the tail end from the lathe? Am I running my RPM's too fast? Any advice anyone can give me?

- Brandon

 

[DaveO]

My guess would be that you are running the lathe too fast. That and/or your bit is very dull. Drilling on the lathe is no different than drilling on a drill press, except the workpiece spins and the bit stays still...and it's horizontal :lol: I drill my pen blanks at around 600 rpm on a DP, and that would be the bottom end of a lathe's speed range.
HTH,
Dave

 

[toolferone]

What is unscrewing from what? Can you be more specfic?

 

[JohnsonMBrandon]

The whole "moveable" part of the tail end will pull out. I think the problem is I am running the lathe too fast. i'll slow it down and see what happens. I was in a real hurry when I put things together last night, and I didn't even check the speed....so I am willing to bet that was the problem.

 

[yellofins]

Brandon,
I've had issues with the quality of the Morse Tapers.
My lathe was doing the same thing and upon inspection found the MT2 taper I was using was not perfect and was not allowing the taper to seat.
Dirt or material in the tailstock can also cause this type of issue.
You can compare the taper to one that is holding well and see if there is a difference.
I have since changed the taper that the drill chuck is attached to and the problem is gone.
Drill press tapers are held in with keys and other mechanical fasteners keeping them in place.

Ron

 

[Makinsawdust]

Brandon,
I do it all the time makiing laminated pepper mills. You want your rpms down in the low hundreds. I had to have some parts made to reinforce my tail stock for this procedure. (Jet lathe) The e-ring and bolt wouldn't stand up to the back pressure. This could be causing you problems too. If you need more help let me know since I'm local to you.
Rob

 

[walnutjerry]

What type bit are you using? Are you drilling flat grain or end grain? That too can have an effect on the drilling.

It sounds as you have an issue with the taper not seating good. I am in agreement with the advice already posted.

Jerry

 

[JohnsonMBrandon]

Thanks for the help guys. Its not really the taper thats the problem. Its the moving part that the taper fits into. I'll try some of the suggestions and see what happens. I have a feeling its just the speed that may be causing my problem.

 

[toolferone]

Brandon, The moveable part of the tail stock should not be spinning at all. There should be a pin or the knob that tightens it in place is to loose. It should only move in and out with out spinning. When you turn the tail stock handle the threaded rod should be turning inside the movable part, threading it in or out. Does this sound like it is the problem or am I still missing something?

 

[JohnsonMBrandon]

Thats the problem, but when you are turning the handle pushing the drill bit in it will all of a sudden catch and pretty much unthread it from the tail stock. It will yank the handle from your hand and turn it really fast. Sorry for the confusion I know i probably don't use or know the proper terminology for all of the parts.

 

[toolferone]

On the side of the moveable piece there should be a groove or notch cut into it. A pin or the locking knob rides in that groove stopping it from twisting. (it should not twist) If it is a seperate pin, it might be loose or to short and not holding it from twisting. If it is the locking lever riding in the groove then you need to tighten the lever so it ingages the groove, but not tight enough to lock it in place.

 

[JohnsonMBrandon]

Tom,

Good call.....i know exactly what you are talking about now. I will check things out again tonight and see if that will solve the problem.

 

[striker]

Brandon,
The "movable part" of the tail stock is called the quill and should not be turning. As tom suggests, you may have sheared off or be missing what ever key thats prohibits the spinning.

In followup to Jerry's comments, if you're using a standard twist drill, it may be too aggressive in its "out of the box form" and overpowering the key in the tailstock. Consider grinding the leading edge or lip area of the drill to a zero rake. This can be done by carefully touching the drill to the wheel on each flute.

Just throwing some thoughts out there........


Stephen