A lathe tool to hold wood from hole in base?

[Perry Hilbert]

From my metal turning days I am aware of how collets work. They grip the outside of round stock. Is there a tool that can grip stock through a hole in the base of the stock. For instance if I have 50 bass wood blanks with a half inch hole in the base. IS there a tool that can be mounted in the lathe and the stock placed over it and then tightened to hold the stock? Sort of the male equivalent of the collet. for instance, I have a few of those rubber expanding gizmos that sand paper rolls are placed on and then tightened with a nut that expands it from the inside. Don't know if that would hold steady enough or not.

 

[Gary Beasley]

Most common is to make a jam chuck. You would want the tailstock holding it as well.

 

[Dennis J Gooding]

I have a set of of expanding steel "plugs" (for lack of a better name) made by Beale tool company. Their sizes range from 0.5" to 1.5" in eighth-inch increments. Each has 0.5" shaft that can be clamped in a suitable lathe chuck. I also have a Vicmarc chuck with pin jaws that will expand into a hole just slightly larger than 0.5". Perhaps there are other jaws available that will go smaller.

 

[hockenbery]

It would help to know what you want to make from these blocks.

If you can use the tailstock for support a pin center with a 1/2” diameter will quickly center and drive the block.
I have a #2 Morse taper center with stepped pins 1/8, 1/4, 3/8, 1/2
You can make one by centering a length of 1/2 rod in a block held on a faceplate or in a chuck.
You could also make a wood Morse taper and glue a length of steel or brass rod in it or turn a 1/2” wooden pin on the exposed end.
I also have a 3/8 diameter spur drive which I could use to drive the blocks with the tailstock. Wraps of masking tape to almost a 1/2 will center the blanks on the spur.

Friction fit on the wood pin may be enough to drive the piece without tailstock pressure.

If you don’t need the 1/2” hole to stay 1/2” you could make a screw center with 9/16 screw.

 

[Bill Boehme]

There are expanding collets for holding small items.

EDIT: I just noticed that my expanding collet suggestion is the same thing that Dennis mentioned.

 

[Perry Hilbert]

Thanks. Looks like the beal expanding collet will do the job. I have been looking for an easier way to mount small bass wood blocks on my lathe for turning ornaments. The hole in the bottom would also lighten them a few grams for actual use on a tree. And I would not have to use the tail stock. As it is now, I am mounting the square blocks in a small chuck, but I lose an inch of stock with the stub that is left inside the chuck and the finished product is just a little too heavy. The expanding collet in the base would permit use of the entire piece and it would be easier to finish the base of the ornament (no spinning chuck jaws in the way and no need to part off)

 

[john lucas]

The Beall expanding collet system starts at 1/2". I would love to have something that starts at 1/4" and goes up to about 3/4" When I make lamps I have a 3/8" hole and simply mount them between centers using a cone center for the tailstock end and a homemade drive center in the other end.

 

[Paul Gilbert]

how about a pin chuck like this one.

View: https://www.youtube.com/watch?v=Ju_PhX4Tx90


You can make them to any size.

 

[john lucas]

I have a pin chuck I made to use for turning my wine stoppers. The trick is getting the bottom of the cutout flat and choosing the right thickness of round bar. I milled 2 small circular holes in mine that hold a small rare earth magnet. That way the pin doesn't fall out when you remove the stopper and fall into the shavings on the floor. I have seen pin chucks up to an inch in diameter. Don't remember who sold them.

 

[Perry Hilbert]

After I watched the reference to the pin chuck, I remembered how a bicycle handle bars fasten into the front steering hub. The post has an angled lower end and the nut on the bolt has a similar angle so tightening the bolt draws the post tight. Just goes to show that the concept of what I want to do is already in use, just a different application. Thanks all.

 

[Don Wattenhofer]

Basswood is very soft so I would think an expanding collet would not work but the screw center that comes with most scroll chucks is what I use to start the bottom of the bowl. The process that I use with my One Way chucks is to drill a 5/16" to 3/8" hole in the waste wood that will eventually turned away in the bowl then mount the blank on the screw, turn the bottom and include a tenon for mounting to turn the inside of the bowl.

 

[Don C Davis]

Perhaps doesn't apply to your finished piece, but Ringmaster has your wood spinning on a threaded mandrel through a 1/2" hole in the wood board.
Here is the spindle mounted mandrel: https://ringmasterlathe.com/product/spindle-adapter-1-14-8/
They also offer a spindle mount for 1-8 spindle
And here's the MT2 taper mandrel: https://ringmasterlathe.com/product/spindle-adapter-mt-2-to-12-13/