Sanding down inlay stone

[Ron Kaplan]

I have used the inlay of stone (lapus and turquoise) to add a highlight rings around a bowls in the past, but it took an excessive amount of sanding to get the inlay flush to the bowl. I followed the inlay instructions saying to use aluminum oxide sandpaper to bring the surface down to almost flush. It seemed to take an excessive amount of time and sand paper to do it. Has anyone out there tried to use power grinding tips (diamond, carbide or stone) to do this and how well did that work?

Thanks,
Ron

 

[john lucas]

I have only done a project or two with stone so I'm certainly not an expert. I use the Blue ceramic discs from Vince and didn't have any problems. http://vinceswoodnwonders.com/ceramic-discs-2/

 

[Dave Mueller]

Ron,
I buy plastic turquoise pony beads, grind them in a small food processor and sort out the fine powder using a tea strainer. Regrind the large pieces. You can then put the powder in the void or crack and use thin CA or epoxy to glue it in place. Once it is hardened, it turns and sands like wood. You can add flecks of black or white to improve the appearance.

If you are inclined to do inlaid pieces like Stephen Hatcher, use the larger pieces of different colored pony beads. Works like a champ.

 

[Bill Boehme]

Real turquoise is hard .... really hard .... hard enough to add a few new words to your vocabulary. You can choose to either let the turquoise stand proud of the surface or to make the recess deep enough so that it will be completely covered by your clear filler. Don't ask how I know this.

 

[Tim L]

I have only done one project that I used Turquoise stone to fill a crack and I used a gouge or scraper to even it up. Then I used sandpaper to finish. I found just sanding the stone wasn't working. Just my experience.
Tim.

 

[Dan Oliphant]

Over the years I have used real turquoise on many a project. The easiest method of use is to crush any course or large pieces down to the size of fine grain sand or smaller. This can be done using a home made stone crusher. Any hardware store will have two or two and a half inch threaded galvanized pipe fittings, about six or eight inches in length, cap one end. Select a smaller diameter fitting and cap to use as a plunger, just make sure it is longer than the outside pipe, you need to hang onto it. The cap used on the plunger may need to have the ridges ground off the outside diameter so it moves freely in the outside pipe, but that is all that is needed.
Don't build up a mound of crushed stone when filling a crack or adding decoration, try to make it just proud of your turning. Using a sharp gauge, finish turn the project as you would any turning, the amount of sanding will not be any more than without turquoise. Your tools will need sharpening more often though.
Brass key shavings can also be used for a nice effect, just use sharp tools.

 

[Bill Boehme]

Dan, I used a galvanized pipe nipple and cap, but my problem was that the nipple was the right diameter (2"), but too short and pieces kept flying out. I used a piece of black gas pipe with a cap that was too long and too small in diameter (3/4") for the plunger. I think that I had the right idea, but the wrong equipment and not enough time.

 

[Andy Chen]

I have used the inlay of stone (lapus and turquoise) to add a highlight rings around a bowls in the past, but it took an excessive amount of sanding to get the inlay flush to the bowl. I followed the inlay instructions saying to use aluminum oxide sandpaper to bring the surface down to almost flush. It seemed to take an excessive amount of time and sand paper to do it. Has anyone out there tried to use power grinding tips (diamond, carbide or stone) to do this and how well did that work?

I wish experts like Stephen Hatcher would chime in on this. Short of that, here is my two cents' worth. I believe Stephen used to use silicon oxide sand paper to start and aluminum oxide for the rest because SiO2 sandpaper is harder but more expensive but he is using ceramic sanding pads these days. (Stephen is a great guy. Not only does he do the most beautiful inlay work but he shares his trade secrets openly online, http://stephenhatcher.com/index.php?n=13) I just posted a segmented piece with lapis lazuli inlays (or should I call them segments because they are not just inlaid on the surface). This presented a real problem because there is no way in hell I would be able to sand the whole block down. I had planned to use carbide cutters to cut it down. That proved to be an expensive proposition. Lapis is supposed to have a hardness of 5 - 5.5 on the Mohs scale and WC, >9 but when I tried to cut crushed lapis embedded in thin CA glue it actually ground off the cutters like taking a steel gouge to an Al2O3 grinding wheel. I ended up using >$100 worth of WC cutters to get to a point that I was satisfied with (but not happy) and just called it quits. (Someone said I created a new material that's almost as hard as diamond by mixing crushed lapis with CA glue. I can't argue with him because I just saw the results with my own eyes, but then why would we pay mega bucks for chemists who invented CBN?) They make diamond rotary burs that are relatively inexpensive. If I ever do this type of inlay again, I think I'll give that a try.

 

[Dan Oliphant]

Ron and Bill, the galvanized pipe caps need to have a flat bottom, don't get the rounded caps, if you do, the crushed material will stay in the center of the larger cap without positive results. If you get pieces of stone wanting to excape when hammered, place the hand you hold the pipe in at the top, or loosly place a rag around the top.

 

[Bill Boehme]

Ron and Bill, the galvanized pipe caps need to have a flat bottom, don't get the rounded caps, if you do, the crushed material will stay in the center of the larger cap without positive results. If you get pieces of stone wanting to excape when hammered, place the hand you hold the pipe in at the top, or loosly place a rag around the top.

Thanks for the tips. I have a lot of turquoise chips that are too large to be used as they are. My large pipe fitting is actually a coupler and the end plug is flat and screws inside the coupling. I think that I just need a short nipple to extend it a few inches. Then I need to get a proper size pipe and cap that fits inside. I did try various ways to cup my hand around the opening, but would up getting some blood blisters while flailing away with a large hammer.