Best method for sanding stone inlays

[Gabe Harris]

My question concerns the flattening of stone inlays. I understand cutting the channels, inlaying the larger stone pieces, filling in the voids with stone dust, etc. The place where I have a problem is finding the best way to sand things down smooth without cutting down the wood surrounding the inlay itself. I've tried sandpaper with the lathe both on and off and have used different types of papers (cloth and paperbacked/crushed garnet papers, normal papers, etc). I've read articles online on using grinding disks, but haven't tried that one yet. I've also heard about some kind of stone blanket that sands the stone only, leaving the wood below it is untouched. If anyone out there has some advice on the subject, along with a link as to where I can buy it, I'd really appreciate it. I'm tired of the "starved horse" look I keep consistently getting when I try to do these things...

 

[John Chianelli]

Have You Tried Inlace?

First I would like to ask the hardness of the inlay material you are using. I try not to use anything over a Mohs hardness scale of of 2-3 but no higher than 4. The harder the inlay material the more difficult it is to make flush, especially with softer woods. The other question you should ask yourself is what resin material you are using to hold all of your stone materials together. The harder the epoxy or resin is made the harder it will be to finish. I prefer to use Inlace clear resin with my inlay materials. It finishes even with the surrounding wood using the my standard sand paper and grits. It cuts with turning tools as well (although you may have to sharpen often depending on the inlay material. I will take inlayed resin and wood down very flush with turning tools then finish sanding as I normally would. I generally make the channels a little deeper since I end-up taking more wood off with tools and subsequent sanding. Inlace also takes finishes such as Nordic oil very well. Inlace resins, materials and dyes can be found at www.inlacebook.com. Hope this helps....John Chianelli

 

[Bill Boehme]

Two other things to consider are leaving the stones proud or having them recessed below the level of the wood and then covering with clear Inlace. The Inlace can be turned with ordinary turning tools but do it as described in the instructions. If Inlace sets up too long before turning, it becomes much harder to turn.

 

[Bill Weaver]

very interesting article.
I myself just bought some inlace kit to work with looking forward to trying this your info has been a big help. Thank You

 

[Dick Hines]

I don't use Inlace but rather real stone chips. Turquoise, lapis and some others. I don't sand the chips I use a scraper to get the chips down level with the wood. Take very light cuts. The stone chips are really hard on sandpaper.

 

[john lucas]

I've turned a lot of Inlace but not stone. Inlace turns quite easily but you have to let the tool do the cutting. If you force the cut it will chip like some plastics do. I use the plastic chips sold with the Inlace instead of stone because it cuts and sands the same way as the Inlace. I buy my Inlace and fillers from www.turtlefeathers.net I notice that Woodcraft is now carrying a lot of the fillers and Inlace.
I do inlay a metal and when sanding these you can easily lower the wood surface around the metal because of the difference in hardness. I would assume stone would be the same. With metal I use a file to flatten the surface so I only have to sand with the finer grades. I have also used very hard sanding discs that do not flex. You can use these very lightly across the top to flatten the metal and stop just as it reaches the wood. This would probably work with stone.

 

[DMcIvor]

I have never inlaid a full ring, rather, I occasionally use turquoise or brass to fill voids. I offer that caveat because I'm not sure my method will transfer to the ring inlay.

The approach I've developed is to set and glue the inlay in the void, trying to get the inlay as close to level with the adjacent surface as I reasonably can. The higher it stands, the more work you make for yourself. Once this sets up and with the lathe off, I use either a Dremel-type grinder or a small (~2") pad on a power sander to carefully get the inlay down to where it is barely above the adjacent wood. Care is needed because at this stage I'm using a fairly coarse grit or coarse stone, and a slip or dip in the disk angle can transfer nasty scratches to the wood surface. With this step completed, I switch to sanding the entire piece with the lathe on.

This pre-sanding or grinding process has thus far avoided the starved horse problem for me.

Oh, I don't use accelerator if I'm using CA, and I find waiting about a day before attacking the inlay with a grinder or sander is best. Too soon and the CA is too soft, too long and it gets too hard.

The other bit of experience I'll pass along is that both CA and epoxy essentially turn to plastic when they cure. Consequently, sanding too long in one spot will lead to over-heating, melting of the plastic, and a smeary mess.

 

[Robert Manning]

Use harder wood and the sharpest possible (new) sandpaper and keep renewing it. Start with 80 or 100 grit. You can also finish the wood with medium viscosity CA glue before cutting your groove and inlaying the stone. CA glue is as tough as nails and will stabilize the wood, but is sometimes difficult to apply without blotches. You can also use lacquer or other hard finish to stabilize the wood.

I have used Turquoise and Malachite this way with perfect results. If the stone is harder than Turquoise, it will be more difficult to keep it level. When sanding, apply light pressure on the stone, and not the wood as much as possible.

 

[Steve Worcester]

Most sandpaper use for wood will not work too well for stone, at least at a pace/wear you are normally used to.

I would look into diamond disks, like theSandingglove sells. I use them for glass and while more expensive, you will get better results on harder inlays.

 

[MichaelMouse]

Don't do stone, but it seems that the carbide scrapers would be an excellent approach. They'd treat the wood and stone/plastic more or less equally. Anyone use them?

 

[Bill Boehme]

I had a broken carbide milling cutter that I tried once. The main problem is that until everything is down to the same level, there is no significant advantage to the carbide cutter. There can be a tendency to rush things along because the carbide cutter is very effective. Going very slow in getting everything to the same level is just as essential as any other method as the carbide is also very effective in knocking stones out of whatever it is embedded in.

 

[craterdog]

Sanding Stone Inlays

I use a lot of stone for inlay, including turquoise, lapis, malachite, onyx and coral. I use the Power Lock discs to sand the stone down and have never had any problem, generally starting with 80 grit and working up to 150 or 180 grit before I switch to sandpaper. Use a good respirator when you're sanding stone, there's a lot of dust generated. You can minimize the amount of sanding by trying to keep the stone below the level of the wood. However, there are times when you want the stone above the wood to create a "terrazzo" look when it's sanded.
Tim Carter

 

[GA Darling]

Well if I was trying to turn stone and had questions, I would send an email to Steve "Spike" Finch of Exotic Vessels http://www.exoticvessels.com/ and ask him.