So this thread is actually pretty informative. A range of good options for rust-proof stone holders, ranging from least > most expensive.
* Improvised solutions. Like HH's boot tray + cinder block + rubber.
* Inexpensive holder made of plastic. For this, the DMT duosharp holders I already have, work pretty well and avoid the rust issue. Adding the new $11 "magnabase" adapter to an existing DMT holder is like a giant magnet that will even more solidly hold any metallic/diamond plate firmly on the holder. For actual stones, I've been using my Baryonyx water stones on the DMT too, they stay put just fine in my current setup just sitting on the 4 rubber feet that are on the top of the DMT holders. Still, though this works, I wanted something with a bit firmer hold on the stone.
* Suehiro stainless holder. $35 for standalone, or $60 to $65 for the kit with additional bases and a small bath.
* The Shapton holder. Looks like $116 for the holder, then around $230 if you buy the add-on Shapton Bath to use it with.
Note: though not part of the holder itself, I found a useful supporting item that I'd been looking for anyway. For some time, I'd been wanting a small, thick, rubber work mat for working on firearms, anything with small parts, etc. I wanted to be super thick and sticky to whatever it's sitting on, so it doesn't slide around. Also wanted raised edges to retain small parts and a moderate amount of liquids if working with those. Found a nifty Tormek rubber work mat, which should go nicely with the Suehiro stone holder and I can use it for knife sharpening, working on firearms, and other home projects.
* Improvised solutions. Like HH's boot tray + cinder block + rubber.
* Inexpensive holder made of plastic. For this, the DMT duosharp holders I already have, work pretty well and avoid the rust issue. Adding the new $11 "magnabase" adapter to an existing DMT holder is like a giant magnet that will even more solidly hold any metallic/diamond plate firmly on the holder. For actual stones, I've been using my Baryonyx water stones on the DMT too, they stay put just fine in my current setup just sitting on the 4 rubber feet that are on the top of the DMT holders. Still, though this works, I wanted something with a bit firmer hold on the stone.
* Suehiro stainless holder. $35 for standalone, or $60 to $65 for the kit with additional bases and a small bath.
* The Shapton holder. Looks like $116 for the holder, then around $230 if you buy the add-on Shapton Bath to use it with.
Note: though not part of the holder itself, I found a useful supporting item that I'd been looking for anyway. For some time, I'd been wanting a small, thick, rubber work mat for working on firearms, anything with small parts, etc. I wanted to be super thick and sticky to whatever it's sitting on, so it doesn't slide around. Also wanted raised edges to retain small parts and a moderate amount of liquids if working with those. Found a nifty Tormek rubber work mat, which should go nicely with the Suehiro stone holder and I can use it for knife sharpening, working on firearms, and other home projects.
I usually rinse it off when done and let it air dry. It's been flash rusting on the threads and inside the nut threads. I'm cleaning that up, but these things are gonna get wet repeatedly so maybe I need a better stone holder.