Drill Chuck Mounting Problem

[JeffB]

Hi all. This is my first posting to this site although I've been a member for almost a year and reading posts and using all the great information for a couple years now. I have a problem I'm hoping someone can suggest a workable/affordable solution for.

I am currently using a very cheap, knock-off lathe (hopefully to be upgraded when finances allow) with a 3/4x16tpi threaded spindle shaft that is not removable or MT mounted. I'm trying to turn bottle stoppers and eventually pen-type stuff, but cannot find a way to mount a drill chuck to the lathe for holding the mandrels these type of projects work best with. Most of the affordable, thread-mounted drill chucks only go up to 1/2" shaft diameter (with 3/8" the most common). I've not yet found an adapter to go down from 3/4" to 3/8" although no problem going the other way (3/4" up to 1" for chuck mounting). Any other ideas?

 

[Vernon Oberle]

collett chuck

Look for a collett chuck of some kind or if you have a scroll chuck the pin jaws will hold most shafts and mandrels. You may have to invest in a spindle adapter from the 3/4 x 16 to 1 x 8 so you can use more tooling. Penn State has alot of smaller holding fixtures and is a good company to deal with.

Vernon

 

[Steve Worcester]

I am currently using a very cheap, knock-off lathe (hopefully to be upgraded when finances allow) with a 3/4x16tpi threaded spindle shaft that is not removable or MT mounted.

There is no through hole or morse taper in the head stock?

If so, not the easiest solution, you would need to have a 3/4x16 to J taper made and then you could use a standard drill chuck with whatever J taper they could make you and it would screw onto the spindle.

 

[MichaelMouse]

Why not pick up a chuck with the proper insert? The Teknatool chucks have pin jaws that will work pretty well as dowel holders, and I imagine others might as well. Push coming to shove, you could use it to hold a bolt with a drill chuck mounted on it as well.

When you get your next lathe, you get another insert and still have the chuck.

 

[JeffB]

I have a barracuda chuck with a set of pin jaws, but since I usually have the #2 jaws on for bowls I rarely have them on the chuck. It just didn't occur to me to use them to hold the mandrel. Thanks for the idea.

I prefer to use the metal bottle stoppers so the mandrel is a smooth round shaft with a threaded end and not a wooden dowel. I hope the pin jaws will have enough holding power so the smooth mandrel shaft doesn't just spin inside them. I can also try the drill chuck on a bolt idea and maybe grind some flats onto the sides of the bolt so it doesn't spin in the pin jaws.

I do have the 3/4x16 to 1x8 adapter and use it to attach many accessories to the lathe. I just hadn't seen one that went from 3/4x16 to the 3/8x24 most drill chucks need to mount on. It would be more secure than holding the mandrel in pin jaws so I'll keep looking while I try all the suggestions.

Thanks again everyone and I'll keep enjoying all the great discussions on these forums. Will try to participate a bit more when I can. 🙂

Jeff.

 

[Richard Baker]

Jeff,
I use a cut off 3/8-16 bolt for a stopper mandrel, and grip the unthreaded end with the center of my chuck jaws, not with the dovetail portion of the jaws normally used to hold a turning piece.

 

[Vaughn]

...I prefer to use the metal bottle stoppers so the mandrel is a smooth round shaft with a threaded end and not a wooden dowel. I hope the pin jaws will have enough holding power so the smooth mandrel shaft doesn't just spin inside them...

I have the same type of bottle stopper mandrel, and have had no problems holding it in the pin jaws on my Teknatools G3 as long as I'm not trying to get carried away with my cuts. If I'm starting with a square blank, I'll use the tailstock to help hold things in place until I have it roughed into a round shape.

 

[Walt]

Jeff, I recently upgraded to a 3520 from a 24 year old Craftsman monopole lathe. I have some #1 morse taper stuff like a 1/2" drill chuck I don't need. Sounds like you do. Send me a P.M.

Walt