Turning stone?

[Skie_M]

The Egyptians and others that used copper to cut hard stones actually used sand embedded into the edges of the soft copper blades. The same method can be used to drill hard rocks. Use a copper rod and diamond grinding dust in the drill press. Advice I was given when thinking of stone handles for my custom knives but I've not been brave enough to try. Tru-Stone on the other hand ...

Slow drilling speed, medium to light pressure, keep it continually moving while UNDER WATER, but yes .... it can work!

Also, welding or sintering some diamond embedded metal onto the end of a steel rod would do it too, and you won't chance losing all the diamond particles with faster water flow or drilling speed, but you STILL NEED TO HAVE WATER COVERING THE BIT AND HOLE AT ALL TIMES to keep it from heating up and coming apart.

Diamond can take the heat with no problem ... the material holding the diamond particles in place are another story!

 

[Skie_M]

Update:

The malachite wasn't too happy ... it seems to be a banded mineral that splits between the layer bands when pressure is applied, so the beads I tried to make are all just little pieces ... which is still fine, of course, as I can just crush those up and use them for malachite inlay now!

If I end up with enough malachite pieces left over, I may even be able to make an entire pen blank from this stuff...

Dust collection is an absolute requirement with malachite, as it's a form of oxidized copper and is fairly poisonous. Dust mask on to be on the safe side, too, even while wet sanding.

I made a lovely paperweight out of Italian blue alabaster... it's just about an inch and a half across, and about an inch high. It weighs 1 and 1/3 ounces, which seems perfect for holding down paper near a window AC unit's fan. I'll put a picture up of it next time the sun's shining and I remember to get my camera out for this.


I still need to get around to turning a pen from my Italian blue alabaster ... no idea which kit I'ld like to use, but as it's such a pretty sky blue color, I'm thinking something gold will pair extremely well with it.


Current project is crushed Tigereye genuine semi-precious stone blank. I'll have a small amount of tigereye that has been crushed into fairly small grains and then held in a matrix using CA, so that one should be able to see the unfinished edges of stone in between the finished edges that are on the face of the pen's surface. The entire pen will then be given a generous coat of CA for protection, but my current quandary is.... how to get the CA and stone onto the blank without gluing it to the mandrel or bushings???

Current idea in the works ... turn a temporary mandrel with bushings out of vinyl rod.

 

[Skie_M]

I still need to get around to turning a pen from my Italian blue alabaster ... no idea which kit I'ld like to use, but as it's such a pretty sky blue color, I'm thinking something gold will pair extremely well with it.

Stoneworking update:
Well, went to turn a bit more Italian Blue and found out why I only made the one desk paperweight ... It's a good thing I have a carbide tool! This stuff is super hard, seems to have some quartz running all through it .... It throws a tiny shower of orange/yellow sparks as I use one of my HSS lathe tools on it, and it takes the edge off in under 10 seconds flat! I've never had this kind of issue with my other alabasters! I'll have to stick with just the carbide as I work this stuff.

I also picked up some Selenite sticks for a random little project... this stuff is even softer than sandstone, splinters and splits extremely easily, and is a water soluble mineral ... It's also relatively clear and fun to play with!


I think that Italian Blue Alabaster pen will have to wait, though I'm keen on getting it on one of my Majestic pens someday! The little piece I have on my lathe right now is for a small side project of mine while I wait for my PSI order to get here.

 

[Skie_M]

It's a sunny day!

It's a pretty little paperweight .... bout the size of a half dollar, I think?

Trying to turn another similarly sized chunk reminds me why I decided NOT to turn the blue alabaster pen ...

While I do have a carbide tipped tool, I have only the one, and the insert is getting a bit dull. And VERY HOT.

I took this off the lathe to show you guys .... the edge that was being used was the sharpest I have left on it, so I'm going to have to chance sharpening that carbide insert or order a replacement. You can see the sides appear to be nearly polished by the burnishing action of the dull edge. It's not even fully rounded yet!

 

[Houtkop]

Turning with Sandpaper

I turned a Verdite tube yesterday, only to have it ripped out of my hand while buffing it, breaking off about 10mm on the one end. Seeing a grown man cry is not a pretty site. Will try and rescue it by squaring of on both sides and adding Malachite pieces on the ends.

But I got off topic there. I have used carbide tools, but on softer stone I use emery cloth backed with a flat piece of wood to do most of the turning.

 

[Skie_M]

I feel for you, man!


I do my final sanding/buffing on the lathe ... I find that most stones are soft enough that Plast-X does an excellent job of buffing them to a gleaming finish. Many are semi-porous or have some type of interior structure that mars the final finish, however, but that typically shows up as an interesting grain pattern that I like. (minor edit for clarification ... I keep my barrels/beads on the lathe through the buffing process! The buffing is with the polishing paste compound and with a lint-free paper towel ... blue shop towel, in fact.)


While working on the more delicate items, I generally just grab my abranet 120 grit and stretch it end to end, wrapping it perhaps 30 - 45 degrees round the spinning blank. This removes stock quickly and efficiently, but doesn't do a whole lot to round it out evenly at the end ... for that I use some emery boards (nail files from a beauty salon) that I buy in bulk at a local place. They are cardboard backed and fairly stiff, so they do a good job. The are also fairly thin and easy to handle, so they work extremely well when working beads.


I don't have any Verdite ... but I recently went to a local shop and spent about 60 dollars on various stones. I got a little bit of emerald, some nice large chunks of peridot, azurite, flourite, and some lovely tigereye... I also managed to grab some moonstone to play with as well.


One of these days, I'll get my old hard drive platters out and set up my gemcutting station and have some real fun grinding and polishing some facets ... till then, it's cabochons for me!

 

[randyrls]

While I do have a carbide tipped tool, I have only the one, and the insert is getting a bit dull. And VERY HOT.

Have you tried honing the carbide? I have a carbide bit that I use for all my acrylics. I use a credit card diamond hone on it when it gets dull. I may have to start looking for another one... While this one is still sharp, it gets thinner every year.

 

[Skie_M]

Yes ... I sharpened that carbide up a good bit, but I think it's my HFT diamond block that just isn't giving me the results I want for that edge ... I just got a pair of lovely 2-sided 400/600 grit diamond surface in (2" x 6") for only $6.99 each. These are solid surface diamond plates, with no gaps in them to mess up my edges ... I also got a planer/chisel sharpening guide.

I'll be sharpening up the old radius edge again real soon, but in addition to those I modified a new bit holder to hold the new square carbide bits I got in from Global Tools. These have very sharp corners... I had fun using them on my more recent abalone shell projects.

 

[Woodchipper]

Did a search for turning marble as there are a few local places where I could get pieces of countertop. I used to sell cabinetry. Marble can have a highly polished finish, but it is still porous. We recommended using a sealer on it at least twice a year.
After reading the thread, I looks like stone turning will be down the road a long way. Thanks to all who contributed!
Edit: The Egyptians didn't build the pyramids. It was done by space aliens. :alien: :alien:

 

[PenPal]

Making a pen from a Wooly Mammoth Tooth I used a metal cutting blade on a three wheeler small Bandsaw. A Carbide Tool that I used until each of the four faces was blunt. Removed the cutter and rubbed it face down on a fineish Diamond file. It took me 6 hours to turn the
Pen Blank and I am still using that one four faced cutter a yr or two later.

I drilled the blank using a near to sized Carbide Tipped Masonry,Steel special purpose drill to near size then a high speed drill to finish size. The first drill is sold around the world as a special purpose drill that will drill through a file or high speed steel or glass. They are cheap enough in my opinion.

I have designed a rock lathe but in my advanced years regard the exercise unnecessary,this is my 85th yr with more pressing projects.

The description of my successful Wooly Mammoth pen I detailed with pics under my name on the forum.

One time in Eastern Turkey I watched a guy of no know real skills using a one hundred year old metal lathe turning masterpieces from Alabaster out on the side of a busy road near a town.

Peter.