It's been discussed several times over the years. Generally people think that the Tormek is too slow and not great for thinning. The horizontal options are used/have been used by JKI, JNS, Cleancut, and
@osakajoe. They are expensive but they work.
Most makers and knife sharpeners prefer belt sanders. They are cheaper, faster and more versatile since they are good for both thinning and edge work. Plus they require less maintenance (grinding stones have to be trued and conditioned frequently)
I didn’t notice I was tagged here. So even though it’s two years late, here is my two cents.
The horizontal wheels are mostly for finishing the final edge or Koba. Not really designed for grinding away material. Some of the hobby cheap small horizontal machines like the Naniwa come with changeable stones. You can get a #400 grit stone for that machine but again not made to do the rough stock removal, just fixing edges and thinking behind the edge with the rough stones.
The horizontal stones we professionally use here are much bigger with a radius of 50-63cm, depending on the machine. The stones are quite heavy and are usually not made to be changed until they need replacing. But again these are only used to put the final Koba edge on the knife.
I would agree that the paper grinders are faster than those of you are thinking of stock removal. But that’s only because most of those horizontal stones are between #800-3000 grit designed more for the final edge. Paper grinder grits go as low as #80-120 so can remove material faster but you need to be careful of heat.
Now if discussing paper grinders and western makers in terms of production, they are much slower than the larger vertical water stones or “kaiten mizu-to” that have a radius around 85cm and weighing 150kgs. You can use a jig to grind much faster and the stone allows for much more variations on how you want to finish. This is one of the reasons many handmade Japanese knives are more affordable than western knife makers. I have not asked any western makers but maybe someone can answer this for me?
How many many of these can they grind, buff, polish, and finish in a month?
- Forged blanks. Heat treated.
- Let’s say, gyuto 210 blades
- VG10 (hrc 60) or equivalent core
- Clad in softer stainless,
I know some western makers will do some stock removal before heat treatment but just state that if you know.