To sharpen bonsai tools, what you need is an oilstone.
A sharpening rod is slightly curved on one side and flat on the other side.
You need the emery rubber to help you clean up the tool before you start sharpening it.
Now you can choose between two sharpening methods. On the one hand there is the sharpening stone. This is the classic and most widespread method. I recommend the oil stone for scissors and grafting knives.
The other method is to use a tungsten carbide sharpener. This method is best for hard-shaped tools. The best example is the branch cutter and the knob cutter.
Oilstone should be soaked properly overnight. That way, there is water in the oilstone so that when you go to sharpen it, the water has not been drained away and the sharpening is done properly.
Before you start sharpening, make sure that the oilstone is flat. If it is a new oilstone, you should not worry about it. You just have to wet it.
If you have used it with other tools, the surface may be uneven.
Often, you will use another oilstone and rub it on top of it to help flatten it.
What that also does for me is that while rubbing the oilstone on the second oilstone, I get a flat surface and it develops a nice sandy, a gritty film on the surface of the the sandstone.
Sharpening the bonsai scissors.
We have a flat edge and the outer edge of the bonsai scissors has an angle.
So when you sharpen it, you don’t sharpen the inside edge which is flat, you sharpen the outside edge which is curved, which is the angled edge.
Make sure that you rub it flat on the sandstone so you get the edge correct.
When you’re sharpening a knife, for example, you actually have to give it a tilt of around a 10-15 degree angle.
If you sharpen a knife regularly, you know that you have to have the angle at 10 to 15 degrees.
When you are sharpening bonsai scissors, make sure that you flush it to the sandstone, and usually, you rub it in one direction. 5-7 times is more than enough when you’re sharpening the stone.
Unless the bonsai scissors is very worn away and you will have to give it serious sharpening.
Remember to use clean strokes across the sandstone. Try not to juggle on it; this is a common mistake but a mistake nonetheless.
Once you finish rubbing it on the sandstone, clean it with some WD40.
Wipe down the scissors with WD40 and wipe it, give it a clean, cleaning wipe with a microfiber cloth or a cloth.
Sharpening the branch cutter
When you’re sharpening the cutters, use the sharpening rod or a sharpener tungsten carbide .
Remember the rod has a curved surface on one side and a flat surface on the outside.
For the outer side of the cutters, the rounded edge of the cutters, use the flat surface so you get the edges smoothed out nicely.
Then on the inside, you’ll have to use the curved surface of the rod.
Best sharpening stone for beginners
This is a great tool to sharpen your concave cutters and knob cutters. Shears are also a great tool.
Here is a sharpening tungsten carbide. It is easy to use, cheap, and easy to store. I really like it because it doesn’t need any prep or water; just hold it tight when you use it.
Use the corner to sharpen the concave cutter and knob cutter so it’s sharpened inside.
Then, hold this corner scrape it down. You must work only in one direction; not back and forth.
1. File inside the bevel edge from the center to tip 4 or 5 times. With only 4 or 5 scrapes, you can see the line that is rather sharpened.
You want to stay inside the surface to maintain the original one; so work only inside with de tungsten corner.
2. File the flat backside of the blade only 1 or 2 times to remove possible imperfections. You may have to do the inside for a bit longer.