Japanese Sharpening Machines

A while back I shared a post on some unique woodworking machines that are typically only available here in Japan. Japan has a fair share of specialty woodworking machinery that aren’t commonly found in other parts of the world, and I’m sure that extends to other areas of work/manufacturing as well. It certainly applies for sharpening. In my time here I’ve come across a some pretty unique sharpening machines, some that are geared towards sharpening hand tools and others for machine blades.

One interesting machine is this grinder/buffer commonly used by wood carvers.

This is essentially a specialty grinder/buffer for carving tools, and this model in particular is the most elaborate style I’ve seen. They also come in much simpler versions with only one row of grinding and buffing wheels, but I can see how this style with a huge range of buffing wheel shapes and sizes would be handy for a full time carvers with a variety of tools sharpen.

There’s a guy in my shop who has a much simpler version of the machine pictured above, and it’s been such a handy tool to have around. Lately I’ve been doing a fair bit of carving to texture the surface of plates and other wood turnings. My style of texture carving is pretty simple so I really only use a few different gouges but sharpening them can still be a challenge. Sharpening carving tools is far harder than sharpening a flat plane or chisel in my opinion. I can get a pretty good edge with handing sharpening, but it takes time and sometimes the results are somewhat lacking. So I’ve started using the power buffer, and it’s been a game changer. The edge quality and level of sharpness on my carving tools after using the power buffer is so much better, and compared to hand sharpening I save a ton of time. Don’t get me wrong, I’m not abandoning hand sharpening, but I’ve definitely found this style of power buffer/grinder to be another great tool for the sharpening arsenal.

I imagine it would be pretty easy to rig up a simple version of a machine like this. Even just putting a buffing wheel on one side of a bench grinder would do the trick for simple tools. But to get the best edge it’s helpful to have at least two styles of buffing wheels; one for the inside and one for the outside of a tool. A flat buffer can cover the outside bevel of pretty much any tool, but for round tools like gouges a round buffer is necessary to polish the inner part of the gouge. Likewise v-gouges require v-shaped buffing wheels. And naturally the more carving tools you have with different shapes and sizes the more buffing wheels you need, hence the range of wheels you see on the machine above.

This video shows a similar machine in action, and also covers some of the pros/cons of these machines.

Here’s another cool style of sharpening machine that I’ve had my eyes on for a while. These machines are designed for sharpening straight blades such as planer, jointer, and super surfacer blades, but at least in one case I’ve seen someone use one of these machines to hollow grind kanna blades.

These machines come in a range of sizes from small fully manual benchtop models to slightly more advanced automatic benchtop models, to full blown floor standing machines. While these machines are probably not the most necessary machine nowadays given the prevalence of jointers, planers and super surfacers that use disposable blades, I still think these machines are awesome. And if you do have an older style machine with blades that need to be sharpened a sharpener like this could give you the ability to handle that process yourself versus having to send blades out to a sharpeing service (for old super surfacers grinders like these are a necessity).

Here’s a video I found on Youtube showing how an automatic benchtop model works. They don’t show it in the video but the grinder head rotates, and first you use the standard round wheel to hollow grind a blade, then you would rotate the grinder head to do a final polish on the edge using the flat front edge of the cylindrical grinding wheel. Also not visible in the video is the water feed which keeps your blade cool during grinding.

So that’s two more machines that I’ve got on my wishlist. The latter machine is definitely less of a priority, and given how much I’ve been carving lately I’m much more focused on finding a used grinder/buffer.

This weekend is Kezurou-kai here in Japan. The big event. It’ll be my first time attending here in Japan. I’m both excited and a bit terrified since I plan to compete along with team Somakosha! I think it’s going to be a great time, and I plan to take as many pictures and videos as possible and report back here after the event.

Thanks for reading.