turquoise cutting question

[Bob Hallowell]

I just filled a big long wide crack in a big bowl and and found out the turquoise dulls my bowl gouges in about 4 seconds. I can't beleive what it does to my crown pm. I just about have the outside shaped and was wondering how the new carbide ring tool I got from Randy at monster tools would hold up. If it will cut it much quicker with out dulling I will use it but I would hate to ruin a new carbide ring for one bowl.

thanks,
Bob

[Glenn Hodges]

Bob, don't even try to cut turquoise with a tool, it is to hard. Get yourself some 60 or even 40 grit sand paper, sand it even to the wood, and then you can use the grit you will use on the wood.

[Frank Kobilsek]

Bob,

Glenn is right, Also if you try to cut inlaid areas that are standing proud of the surface of the bowl you can just plain rip them out of the piece. Sometimes they will pull wood with them. Once you get down to close to smooth with the 60 grit a big heavy scraper will get the last little bit.

Lastly Do not inlay and then let the CA dry to long. It is easier to machine as soon as it is hard enough to machine. Leaving cure over night the composite of CA and stone will get extremely hard.

Frank

[Robert McGowen]

A second opinion here. On the turquoise inlays that I have done, I sanded down the outside of the area to be filled to 220. I then filled with the inlay and used a square scraper to smooth out the inlay. Yes it does need sharpening often, but that is the nature of the beast. Try not to touch the wood with the scraper. Once it is flush with the wood, give both the wood and inlay a quick final sanding. The problem with trying to sand the entire area after the inlay, is that the sandpaper will remove the wood way faster than the inlay. It might start out flush, but by the time you finish sanding, the inlay will be standing proud again. Just the way I do it.

[Bill Wyko]

I use a product called inlace. The site is www.inlaceonline.com (http://www.inlaceonline.com) This will make your life easy.:D I tried real turquoise too. Destroyed tools in seconds.

[Glenn Hodges]

The inlace is nice, and I have used it, but now I prefer the big nuggets of real turquoise and malachite glued in then medium pieces of the same glued, then fine particles glued in to fill the voids around all of large and medium pieces. It is the same with everything else, "Different strokes for different folks." This preference of difference inlays and shapes is what makes turning so interesting and prevents it from becomming borring.

[Bob Hallowell]

Thanks guys but you see I was smart:confused: and filled the cracks with the epoxy/turquoise mixture when it was finished drying in the rough form so it now needs trued up and takeing down to size. so I have to use a gouge or the hunter style tool on it.

Bob

[Barry Elder]

Don't know that I would want to test a Hunter type tool bit, but carbide should be the ticket. But neither do I know whether the stone will break instead of cut.

[neil mackay]

Bob, Look around and see if you can find a tungsten carbide scraper this will take care of the problem.
With a TCT scraper you can gently remove the excess and then go the sanding later.

[Gordon Seto]

There is a new tool (Easy Rougher) in the market. It has a carbide cutter. This is designed as a roughing tool, but people has reported it has good result turning alabaster, which is also a tool destroyer.

Joe Herrmann, editor of Woodturning Design Magazine did a demo for our Club last month. He showed it to our members.
You can see the tool in action following the YouTube link.
http://www.easywoodtools.com/events.htm

Joe is a member of our Club. He thought it may be something new and different; so he introduced and pass out information about this tool to us. He didn't recommend nor endorse the tool. He also said he has no relationship with the sale of this tool. It is a very well made tool, each cutter has 4 faces with 1 to 4 markings. When one face gets dull, you rotate to the next.. I just purchased mine. (I am a tool junkie)
From other discussion, he also has different cutters introduced. They are going to be carried by CSUSA and sold at the AAW Richmond Symposium.

I also have the Hunter tool, I think the Hunter cutter has a tiny curl up lip. If everything equals, I guess the Easy Rougher cutter may be able to stand up from abuse of super hard material. That is just my theory, I have no actual experience in using either for cutting turquoise.

I understand the maker Craig Jackson has 100% refund policy including shipping if you are not satisfied. Try it and report back.

[Bernie Weishapl]

I would go ahead and give the hunter style tool a go. With the carbide cutter it can be cheaply and easily replaced. About all you have to loose. That is why I quit using turquoise.

[robert hainstock]

there must be a website somewhere to tell the relative hardness of various minerals, and also carbide. If memory serves, crbide is not far below diamond. But google it first to be safe. LUCK!:eek::):)
Bob

[Gordon Seto]

Usually we can't get hardness and toughness at the same time. On turning tool we want to temper the steel so it won't be brittle. I believe that is why todays high tech tool steels are beyond the control of ordinary home work shop.
kudos to those who do the research and experiments.

[byron constantine]

Use 60 grit silicon carbide to get it down to the wood and then use aluminum oxcide sandpaper.
Byron

[Johnny Fischer]

This should answer your questions about hardnesses.
Hope it helps.


Rockwell & Brinell Cross Index
Rockwell


(Rc)

Brinell

(BHN)

20

226

25

253

30

286

35

327

40

371

45

421

50

475

55

546

60

613

65

739




Typical Hardness Values for Common Materials


Material

Brinell Hardness

Pure Aluminum

15

Pure Copper

35

Mild Steel

120

304 Stainless Steel

250

Hardened Tool Steel

650/700

Hard Chromium Plate

1000

Chromium Carbide

1200*

Tungsten Carbide

1400*

Titanium Carbide

2400*

Diamond

8000*

Sand

1000*
* Vickers Hardness






MOHS SCALE OF MINERAL HARDNESS

Hardness

Mineral

Everyday equivalent


10

Diamond

synthetic diamond

9

Corundum

ruby

8

Topaz

sandpaper

7

Quartz

steel knife

6

Orthoclase/Feldspar

penknife blade

5

Apatite

glass

4

Fluorite

iron nail

3

Calcite

bronze coin

2

Gypsum

fingernail

1

Talc

baby powder





Some GEMSTONES hardness

Hardness

Gem


10

Diamond

9

Sapphire, Ruby

8.5

Crysoberyl, Alexandrite, Cats eye

7.5 - 8

Beryl, Emerald, Aquamarine

7.5

Zircon

7 - 7.5

Tourmaline (Elbaite, Dravite)

7

Quartz (Amethyst, Citrine)

6.5 - 7.5

Garnet (Hessonite, Rhodolite, Spessartine)







GEMSTONES
Mostly gemstones have a hardness of 7 or more. But there are some gemstones with lower hardness for example Jade(6.5), Lapislazuli(5-5.5), Opal(5.5-6.5), Turquoise(5-6) or Feldspars(6-6.5) like Labradorite, Amazonite, Moonstone, or Sunstone













Another MINERALS hardness

Hardness

Minerals


9

Sapphire

7.5 - 8

Beryl

6.5 - 7

Olivine (Peridot), Jade, Spodumene (Kunzite), Epidote, Cassiterite

6 - 6.5

Iron Pyrite, Rutile, Albite, Prehnite, Benitoite, Epidote, Cassiterite

5 - 6

Turquoise, Hematite, Augite, Diopside, Moldavite

5 - 5.5

Goethite, Natrolite, Datolite, Analcime, Wollastonite

4.5 - 5

Apophyllite, Scheelite

4 - 4.5

Platinum, Smithsonite, Wolframite

3.5 - 4

Aragonite, Ankerite, Dolomite, Azurite, Malachite, Sphalerite, Chalcopyrite, Cuprite, Rhodochrosite, Strontianite, Stilbite, Heulandite, Mimetite

3 - 3.5

Barite, Celestite, Cerussite, Atacamite

3

Wulfenite, Vanadinite, Bornite

2.5 - 3

Gold, Silver, Copper, Galena, Anglesite, Mica Phlogopite

2.5

Micas (Biotite,Lepidolite)

2 - 2.5

Cinnabar, Amber, Mica Muscovite

2

Sulfur

1.5 - 2

Molybdenite

1 - 2

Aurichalcite

[Bob Hallowell]

Well I got'er done with the Randy's carbide ring tool. Seem to hold up pretty well. then took some final passes with the bowl gouge. I wil post a pic tommorow. Thanks for all the help.

Bob

[Richard A. Rivera, M.D.]

There are various scales for "hardness", but the people into rocks use tha Mohs scale. It is 1 -10, with chalk (gypsum) as 1 and a diamond as 10.

tempered steel is about 7-8, turquoise is 5-6, but there are a lot of colorful mineral in the 4-5 range which will work for inlay and have the strength to retiain their finish.

When you call on a lapidary store for stones, make sure you tell them you want a product which has a Mohs rating of less than 5, this will make finishing a lot easier.

good luck.

[Dick Strauss]

Bob,
Get yourself a few of those cheap AR-6 or C profile carbide tool bits and round off the corners of the the metal backs as necessary to fit a handle. You can get the C2/C5/C6 carbide that will hold up well against stone. I've turned soapstone and metal with no issues. It is best to use the tools like a scraper to get the best finish with stone. Once yu have the shape you want, just sand as usual...

3/8" AR-6 C6 Bit
http://www.use-enco.com/CGI/INSRIT?PMAKA=383-0035&PMPXNO=940856&PARTPG=INLMK32

Main tool bit page...
http://www.use-enco.com/CGI/INPDFF?PMPAGE=153&PMITEM=383-0035

FYI-The C6 bits are very hard and will chew up a green Sillicon Carbide wheel in a hurry so be prepared. They cannot be shaped with white wheels (DAMHIKT).

[Allen Neighbors]

I use a lot of turquoise. I buy unstabilized turquoise, so it's not as hard as jeweler's stabilized stone, but it's still stone. I mix it with epoxy and fill voids with it, proud of the wood. I also allow it to harden and cure overnight before I try to finish it because there's less of a chance for tearout. When I have some that needs to be turned down (like on the inside of a piece, and the outside of some bowls and vases), I use an Oland Tool with a 3/16" cutter. The cutters I buy are the kind with 10% carbon, from UseEnco.com. They do require some additional sharpening, but will cut the turquoise better than any other tool I've tried... much better than standard HSS. I wouldn't try my Hunter ring-type cutter on it, because I believe the stone would break the cutter in a heartbeat. It takes a faster speed, and a lighter cut to cut turquoise. But it cuts. Robert is correct when he says using sandpaper will take the wood down faster than the inlay. But care in handling will produce fine results. Keep after it. You'll get it. :D

[Joe Melton]

Absolutely do not sand malachite. I would avoid working with it altogether.
Joe

[byron constantine]

Silicon carbide paper will cut it down then use regular sand paper. I got
this info from a turner in calif that uses turquoise inlay on platters. I
haven't tried it yet.
Byron

[Wes Henson]

Just a thought to consider is how brittle carbide is. I’d defiantly go for a small carbide cutter or get some carbide bar stock from Enco or MCS. I’d hate to see a large piece of carbide shatter against the stone because it doesn’t have as much flex as steel.
There is an article here that shows what one guy did with crushed stone.
http://www.woodturningonline.com/Turning/Turning_articles.html (http://www.woodturningonline.com/Turning/Turning_articles.html)
Looks like he power sanded it. - not sure if this fits your situation
Good luck, would love to see the bowl when it’s done and hear how you complete the project.

[Bill Wyko]

Who ever figures out how to do this right, please post. I have about 5 lbs of turquoise I'd like to get some use out of. :D

[Bob Hallowell]

Just a thought to consider is how brittle carbide is. I’d defiantly go for a small carbide cutter or get some carbide bar stock from Enco or MCS. I’d hate to see a large piece of carbide shatter against the stone because it doesn’t have as much flex as steel.
There is an article here that shows what one guy did with crushed stone.
http://www.woodturningonline.com/Turning/Turning_articles.html (http://www.woodturningonline.com/Turning/Turning_articles.html)
Looks like he power sanded it. - not sure if this fits your situation
Good luck, would love to see the bowl when it’s done and hear how you complete the project.

This thread is a few months old. I used my carbide ring tool. I am going to look into those inserts though. Here is a link to the bowl in question I posted http://www.sawmillcreek.org/showthread.php?t=83552

Bob

[Dick Strauss]

Bob,
I wouldn't chance my $20-25 Hunter/Monster carbides on stone. Try the carbide cutters and I'm sure you'll be pleased.

I used them on a combination walnut and white solid surface piece that was giving me fits. I couldn't get a smooth cut at the transition from one material to the next until I tried the carbides.

C2 is the softest carbide (least wear resistant) but the most shock resistant while C6 is the hardest (most wear resistant) but most brittle of the bunch. I went for C6 bits and haven't had any problems but they are the hardest to sharpen. C2 carbide is still plenty tough and is easier to sharpen.

[Chris Stolicky]

I have not used large quantities of turquoise in turnings, but I have used it quite a bit in pens, with CA. I just use sandpaper to grind it down flush with the wood. I usually use 150, but that's because its usually not a large gobb that needs to be sanded. Once it pretty much flush, I continue going through the grits.

[Greg Savage]

Who ever figures out how to do this right, please post. I have about 5 lbs of turquoise I'd like to get some use out of. :D

I've been doing inlay with turquoise for about 15 years. I use a coffee grinder to crush the stone into varying degrees of coarseness. Turkish grind is my favorite! HA!!!!

Wait until the work that you are going to apply the TQ to is dry and in its final form ready for final sanding. I use a dental drill to clean up and under cut the void to be filled with turquoise.....Much the same way as a dentist fills a tooth. Sometimes "body work" is necessary to build walls and fill in areas that will use too much TQ.

After your prep work to the void.....fill the void with dry TQ and level it off. Drip CA onto the TQ. It will penetrate quickly and cure soon enough.....Don't use accelerator immediately so you don't cause the CA to cure too quickly and "foam up".

I usually start with 80gr aluminum oxide ripped from 2 inch shop rolls. Don't cause yourself more work than necessary with the carbide tipped tooling unless you have a real problem here for some reason. If the TQ is reasonably well levelled off and you are using hard dense woods, everything should sand back uniformly.

If you'd like to place larger stones in with your inlay, you may have to do some local hand work. I use an Ingersoll-Rand air grinder with 40gr metal grinding discs for these instances.

There is a thumbnail on my method....I hope it will work for you.

http://www.peppermillguy.com/




BTW.....I hope i'm making sense here. I just had a much longer more detailed post disappear when I previewed my post.....needless to say, I wasn't happy about that and then quickly re-wrote the post.

[curtis rosche]

could you just use a dremel?

[Greg Savage]

could you just use a dremel?

Yes...It all depends on how fine of an area/void/crack you intend to inlay with turquoise. I like the dental drill because because of the size and weight of it. A Dremel can be very fatiguing on your hands if you use it for any length of time doing fine work. But, if you aren't trying to clean out very tiny cracks, it may be all that you need.

[Mike Hunter]

Bob

I would like to work with you on this project. The carbide is in a compression mode which makes it a very effective cutting tool. It all comes down to hardness of the material being cut and the hardness of the cutting tool material. You also need to be aware of the surface footage or RPM of your machine. Everything needs to be married to make the tool an effective cutting tool.

Please call me at 612-718-7926 and together, lets make this a project to work on together.

Mike Hunter