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Clamping Rocks in a Saw Vise

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As I was trying to cut some optical quartz into thin slices the other night - and cussin' every time the quartz slipped in the vise, I started wondering how others locked their rocks in their saw vises so they wouldn't move. I am sure there are a lot of tricks you use to do this. So please send a note to LapDigest with ANY tricks or ANY advice you have for tightly clamping irregularly shaped rocks in the saw vise.


I use Elmer's glue to "dop" my rough rock to a 1x2 or 2x4. If it is very irregular, I will take small pieces of dop sticks and push them under the rough until I have it level and orientated the way I wish to cut it. I will sometimes use this method just to cut a "false" table in the rough so I can grab it better to make the actual cuts. By this I mean I will use the procedure listed above but make just a single cut on the opposite side of where I really want to cut the rough. By doing this I now have a flat surface I can grab in the vise or I have a nice flat surface to glue my 2x4 dop to and like water glass I can put the heal of the stone in water and let it soak to remove the 2x4.


I corrected my problem of securing odd shaped specimans in a vice by simply drilling 4 holes in the side of the vice closest to the blade (obvious). Two holes in the rear vice plate & two holes in the front vice plate. I then threaded the holes and inserted four bolts in these holes, then tightened them. The holes only need to be 1/2 " deep and 1 1/2 - 2 " apart. The bolts only need to be protruding out 1/4 - 1/2 ". Bolts should have a flat head, which ives a much greater grasping power than your regular stove type heads. The irregular shaped speciman can then be clamped not in the vice but simply into these protruding bolts. This ended my problem of specimans coming loose, and at the same time ended needless waste of the speciman that was in the actual vice.

Bob Morgan
Morgans Antiques-2nd Hand-Rock Shop
1402 E. St. Patrick Street, Rapid City, S. D.
605 388-8880

G'day; I use a chain/pipe vice. This is a vice that plumbers and engineers use to hold pipes and thick cylinders whilst cutting them.

The jaws are shaped in two V's and move to and from each other with the usual sort of screw, but the V's are stepped. One selects an approximate distance for the jaws, and then a chain - exactly like a motor-bike chain (do they still use them?) is passed over the top of one's rock and the end has a kind of hook with a cylindrical nut attached. The hook is pushed into the chain, and the cylindrical nut is pressed into a slot, and upon turning the nut, tightens the chain against the rock. A little bit of - well, reasonable abuse will show whether the rock is held really fast and away you
go! Very difficult to describe without a sketch, but - well, like I said, try and imagine it.

Having got a flat face to the rock, I 'glue' it with dopping wax to a small hunk of scrap timber cut like an L This can then be held in a normal lapidary saw vice. My slabbing and trim saws are home-made setups which have worked well for about 25 years. Water coolant with the slab saw, and a very light Shell Co. transformer oil is used with the trim saw. I need waterproof aprons with both these and also the grindery and polishing setup. That's home made too. Think about what you need to do something. Look around at what you, your mates and the local junk shop have, think again only a bit sideways this time, use a few tools, borrow from your long suffering mates those you haven't got BUT RETURN THEM PROMPTLY - and soon you have what you need without taking out another mortgage on the house! This way you double the fun!


John Burgess,

Attach a piece of 1/4" plywood to the inside of both jaws of your vise. When you clamp an irregularly shaped rock in the vise, the protrusions will sink into the softwood and
nothing, but nothing, moves.

Dale Brown
Rockhounds Esq.

I have a variety of odd shaped wedges that I use. Some of them are hard wood, some are soft. I also use "plates" of hard and soft wood to get a grip on the rocks. The most important points are getting contact on at least three areas of the rock and then clamping so tight that you cannot twist them out of the vise.

Another trick is to mix either plaster of paris or mortar cement into a milk container with your rocks (great for small pieces). Place the rocks into the container so that each rock is surrounded by the "mud" and let set up for a few days. Then peal the container off and clamp into your vise and start cutting. (By using a cementious material-NOT concrete,
the sand aggregate will also aid in sharping the saw at the same time. If you break up small pieces of a grinding wheel, you can cut lots of jade by doing this trick with no problem of binding.
Another trick is to use a matching size of wood that has a smooth face and match it with a smooth face of a cut rock. Glue this with a water soluable glue and cut it until the last cut, then soak it off in water to retrieve the last

Better yet, get some Aluminum angle and then dop a rock on it! Heat the aluminum and rock with one of those disposable propane torches.
This works only with a cut rock (flat face).

This is a good solution and best for the time factor as you don't have to wait for the glue or cement to cure before cutting. Dop it as you would any stone-clean, free of oil, etc. This is great for getting good material out of a heel.

Found this tip in a Rocks & Gems magazine. Or maybe Gems &
Minerals...I don't remember.

Hale's Note: Thinking about my problem of clamping optical quartz for the sawing of cover slips for doublets, I noted that the jaws are now lined with maple, which is very hard.
When the quartz is clamped up tight into the maple, it still only makes point contacts. If I had a crushable wood on the jaws, the quartz could crush into the wood fibers and the
contact then would be an area, giving much greater friction. I went on Woodworkers newsgroup and asked about crushable
woods; the advice I got was to try poplar or basswood, which I will do this week. They also suggested that I might use rubber heels - or something similar - which is also worth a
try. Yes, I know I could glue it to a piece of wood, but doing something new and different is more fun!! hale)

Hale, you said you were trying to cut a thin slice of optical quartz. If it was a fairly small piece, I may have a solution.

A friend of mine wanted a very thin slice to use in intarsia and dopped his material on a facet dop. He mounted it on the 45 degree attachment used to make facet tables. Next he put an 8-inch diamond saw blade in place of the facet lap. Using a lot of water drip he gently nudged the material through the
saw blade to get a smooth cut. He then used the vernier to lower the piece the several millimeters he wanted and proceeded to make the next cut and got an even piece that was
thin and uniform.

I thought that was a neat trick and could be used to make thin slices of material that was small enough to fit in the faceting area. Even a 6 inch blade might work.

David Tuttle
non commercial use permitted
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