Brush Cutter- Tanaka TB-21HS

My Tanaka TB-21HS Brush cutter with a Mr. Kuroba four blade disk.

Here in Japan, people have postage stamp lawns, if any. So nobody has large lawnmowers. And there seem to be a lot of mountains here. So brush hogs are not too practical for most rural people. At least not enough to make a market to sell them. So we are left with the ubiquitous "Kusakariki."
Mine is an utterly average machine. Works well, a bit noisy of course, but does the job.
In Japan, most people use a "Chipsaw" blade, basically a disposable sawtoothed cutter. I used to use one too, but the waste! Hit a stone and the teeth fall off, the blades dull and won't cut. Then my good friend who does this for a living showed me his machine. Wow. He has one mean looking blade on it. A thirty blade steel disk that he keeps razor sharp with a file. And they last so long! After a few hundred sharpenings, the blade will have worn down to 20cm or so and it will be too difficult to get the speed to cut properly, and you need a new blade.

I decided to experiment with a four blade disk by Mr. Kuroba. It is recommended for soft stemmed grasses and weeds, and general use. It is an OK blade. I think I will use an 8 blade disk next however, since I have noticed that it is cutting a bit raggedly. It is easy to sharpen. I just use a plain old metal file, give it a few strokes at a fairly steep angle. I try to keep the blade straight, but wear and tear on the outer edge is starting to round it.


I also use a string trimmer for work around the house, and anywhere there are too many rocks or tree stumps that a blade might catch on. It is an insert type. You just slip the 20cm long nylon cords through the holes, wrap it around and through the exit on the outer ring.

Disk and plugs

thread it through

flip it over and to the outside.

Square cords to cut more efficiently.