Tools - Vise for Stone Drilling

Vise for Drilling Stones for Beading

[Updated May 18, 2015 to add measurements.]

A friend of mine asked me to make him a vise for holding semi-precious stones so that holes could be drilled in them to make necklaces and such (see youtube clips referenced below). Unlike the method shown in the youtube clips, he wanted to be able to hold the stones in a vise. For this purpose I made the vise shown on the left, with two pairs of soft jaws made of UHMW plastic.Since the stones are drilled under running water, the vise needed to made of materials that would not rust or corrode. I used aluminum for the vise jaws and body, stainless steel for the guide rods, and brass for the vise screw (with an aluminum fluted knob).

The vise is designed so that a stone can be drilled from both sides by simply flipping over the vise.

Here are a couple of youtube clips on drilling semi-precious stones:

Building the Vise

Rather than make a build log for this project, I will simply point out some of the features of the vise.

The soft jaws for the vise are made so that they can be removed from the vise without disassembling the vice body. Since the plastic (UHMW) jaws are not screwed on, they can be removed by opening the vise fully, and them "popping" the jaw out at an angle. Two sets of jaws were made, one set with horizontal and perpendicular V-grooves, and the other set with a single deeper vertical "stepped groove". Jaws are inserted into the vise by reversing the procedure.

The pictures below show the vise screw and insert nut.

  • The brass screw (1/2" - 13 tpi) was too long to be made to full length in my lathe, so I threaded as much length as possible, and finished it with a threading die.
  • The brass insert was made to avoid having the screw run in an aluminum thread, as I wanted to avoid the galling that frequently occurs with aluminum. The brass body was turned on the lathe, and threaded with a 1/2"-13 tap.
  • The hole in the vise body for the insert was made on the mill with a boring head, and was made .002" undersize to allow for a shrink fit. The shrink fit was done by heating the vise body piece in a toaster over (450 deg. F for 20 minutes), while the insert was kept in the freezer. I was happy to see that the cold insert went into heated piece with just a slight push, and was held firmly in place when the body piece cooled.

If I were going to do this over again, I would probably purchase acme threaded brass rod, both because this is a better thread form for this purpose, and also to address the issue of being too long for my vice. In that case I would also need to purchase an acme nut or an acme tap (or consider turning an inside acme thread on the lathe); alternatively, standard threaded brass rod could be used.

Vise Screw

Insert (nut) for screw

Insert and screw

The guide rods (holding the fixed jaw and the vise body together) were made from 1/2" stainless steel rod. After turning the ends as shown, the rods were polished with successive grades of abrasive cloth to a smooth finish. The picture to the left shows the rod half-polished on the bottom end, before polishing was complete. The polishing had the benefit of reducing the diameter slightly, and this together with the smoother finish helped the moving jaw slide more easily.

Where the end of the vise screw fits into the moving jaw, and thin brass disk was inserted to act as a bearing surface for the drive screw.

A fluted knob for the vise screw was made by first turning an aluminum blank on the lathe, which was then drilled and tapped for 1/2"-13 thread. The threaded blank was then screwed onto a mandrel made for this purpose, and mounted in a hexagonal collect block. Six flutes were cut using a 0.250" ball end cutter.

Blank for knob (already tapped).

Making flutes with collet block.

Completed knob (mandrel in back).

A flat was milled on the threaded rod to act as a seat for a set screw. Alignment marks were made on the end of the screw and knob (with a Dremel tool) to facilitate aligning the set screw with the flat, and the knob was drilled and tapped for a set screw.

Flat for set screw.

Alignment mark.

Here again is the completed vise (in the closed position).

Vise Measurements

I didn't make any plans for this vise - I just came up with a design in my head and built it from materials I had on hand. However, here are some dimensions for those who are interested:

  • Aluminum jaws: 4- 1/2 L " x 2 " H x 3/4" W
  • Guide Rods Diameter: 1/2 "
  • Threaded Rod: Approx. 6-1/2 " between set screws( 1/2 " diameter, 13 tpi )
  • Crown or aluminum handle: 7/ 8 " diameter
  • Plastic Jaw: 4" W