Turning Stone.

[taycat]

not sure where to put this so trying here.
just seen an instructable on making rings from meteorite ( http://www.instructables.com/id/Meteorite-Ring/ ).
looks like he is using normal tipped tool for turning it.
my daughter saw it and wants to make herself a ring out of some slices of stone she has not sure what it is.
how to do it?
same way as in video?
made rings out of metal before so know basics just never out of stone.
cheers

 

[Billh50]

Cutting stone usually takes carbide tools. He said he bought the meteorite piece off Ebay. So I would not be so sure that is what he was cutting. I cant see using HSS drills on stone unless it is a soft stone and then it should dull the drill readily. I have drilled stone and glass with carbide but never HSS. I have never tried turning or boring any though. Maybe someone on here has and will answer your questions.

 

[Heckle and Jeckle]

Thinking a stone ring might be ......... pretty brittle and not long lasting.. better make a few

 

[RJSakowski]

I would think diamond tooling would work. I would expect that the process would be one of abrasion rather than cutting. The people making kitchen counter tops work stone routinely, drilling holes and shaping, using diamond tooling. You might try a diamond dressing tool for grinding wheels.

 

[francist]

My sister had a jade ring back in the 70's -- she wore it for quite a while but then it eventually did crack. As for the meteorite, they're not all the same. Some are quite stone-like while others are very close to being a workable natural iron. Would likely make a difference which one you chose.

-frank

 

[FLguy]

I do some lappidary, and 90 percent diamond tooling is what I use. One of my bandsaws has a diamond blade, thought it so unusual when I bought it but now it gets a lot of use in the shop more than stone work.

 

[Kenny G]

I also dable in lapidary and am a retired geologist, francisst is correct there are stony,iron and a mixture of the two. The iron nickel display a Widmanstatten pattern of elongated iron , nickel crystals,(very cool) these may be machinable with carbide or HSS not sure. The stony meteorites are more like a rock? and are harder to identify because they are pretty plain looking. As FLGUY said most cutting is done with diamond tools but sanding and forming is also done silicone carbide. The main problem I see using a lathe is usually water is used to cool and keep harmful dust particles down. These dust particles are often times heavy with Quartz or quarts like minerals. These can be very abrasive and when water is added produce what I call rock snot which make it even more abrasive and extremely hard to clean. They actually make and sell a rock lathe I have no experience with them but believe they are more like a wood lathe. I don't think I would encourage using a metal machining lathe or mill might turn out to be a very expensive screwed up machine.

 

[savarin]

I would use a drill press with different diameter core drills.
Glue the slice to a wooden base, make a damn around the slice of Plasticine or silicone, clamp the wood to the drill plate, keep it submerged and go slow.
A diamond core drill just needs the water but if you make your own out of say soft iron water pipe then use a slurry of silicone carbide grit and water.
Keep lifting the drill to allow the grit under the flat edge of the drill.
drill one size through into the wood then swap to the next drill size for the other .
I cannot remember if it makes any difference whether you start with the inner hole or the outer diameter.
If you make your own tool you dont need much depth so its easy to turn the diameters to an accurate size keeping the cutting edge parallel and flat and then cut vertical slots to allow abrasives and sludge somewhere to go.
Make the flat cutting edge slightly wider that the flanks (both inside and out) so it doesnt bind in the cut.
I have cut a 12"dia x 1" thick glass disk with this method.
The carbide grits wear down pretty fast and need regular topping up.