HOW TO SHARPEN & MAINTAIN BONSAI TOOLS

[Luke308]

http://www.youtube.com/watch?feature=en ... 6oKDQ&NR=1
Found this video quite interesting especially the use of a fish hook convex whetstone for the knob cutters.

I personally would have thought there would be more effort involved in sharpening, but this chap makes it look so easy.
Can any of the more experienced members fault his technique???

[Jester]

Hi Luke, I think I can. For starters, one of the most important things in sharpening a scissors is the angle. His technique of holding both in mid air in my opinion, makes for a very ineffective, innacurate and possibly slightly dangerous method of sharpening. Your chances of maintaining a consistent angle without one of those two items on a flat surface is slim. The stone he uses is of a very crude / rough grade. I posted an artice here some time ago on japanese wetstones and made the point that there are 3 stages when applying a stones to a blade: "Grind" (to bring back the shape and take out any big chips), "Sharpen" (as the name implies), and "Hone/Polish" where you work to get a razor's edge. To be fair, in some cases not all 3 stages are required but the man in the video, from what I recall did not really go into any detail as to what condition the scissors were in to begin with. In any case the implication seemed to be a "one method fits all" technique.

If you wanted to get more specific, you could talk about the various sharpening tools and grades of tools available for sharpening. I personally use japanese sharpening stones of various grades both synthetic and natural as well as nagura stones. The sharpening stones range from a 400 grit to 10,000 grit. The number of stones I pass my blades through will vary depening on the condition of the blades and the quality of steel. The cheap carbon steel scissors he was sharpening consisted of a very soft metal and is generally easy to sharpen but also blunts quickly. Good quality stainless steel can often be a lot harder to sharpen but will often hold it's edge longer. The amount of sharpening he applied would have hardly made a difference to the blades. It would barely have been enough to file back my finger nails.

I also winced when he used a hammer to "tighten" the looseness in the one of the tools by hitting the pop rivet. What would happen if he had hammered a little too hard? To be honest with you, all bonsai shears should be joined with a nut and bolt like good quality barbers scissors so thay can be pulled apart and sharpened with more ease. I totally object to the use of a pop rivet. This is one area where the japanese should know better.

There is so much more I could mention here but hopefully what I have written kind of answered your question.

John
(Previous post on stones is here) viewtopic.php?f=20&t=10744&start=0&hili ... ing+stones

[Luke308]

Thanks Jester.

I remember reading your thread and that is what has got me started on searching the web for info/techniques. I think your research of the Japanese is great, but I can't see how you could sharpen a knob cutter or concave cutter with those whetstone you refer to. The concave cutter you may be able to, but I am not certain.

I am at the stage where I am upgrading my tools to Japanese tools and I am wanting to know how to keep them in the best & sharpest condition.

When Grant Bowie was at our club recently he mentioned the most important thing that often gets overlooked in bonsai is sharp well maintained tools.

I would be interested if you could provide some more info & or some links on how to maintain a nice sharp edge on all tools including knob and concave cutters. I did find this in my searching but the price put me off http://www.maxistools.com.au/product/dm ... extra-fine $109!!!! Looks like you could sharpen knob cutters with no worries though??

[Jester]

Hi luke, as far as knob and branch cutters go, you are obviously more limited in your approach to sharpening and I have far fewer objections to the man's technique here. His use of the curved waterstone makes sense as it can be used on both the inside and the outside although I would still recommend leaning the tool on something in order to maintain a more consistent angle. The tools on the website you created a link to may or may not of any much use to you as it would depend on the size and curviture of the tool against what it is you are trying sharpen, so in this respect I don't know that I would spend too much time l;ooking for space age answers.

Ooh crikey I just had a brainstorm (Thankyou PepsiMax!!) I don't know about you, but I have a Dremel. For the Knob cutters, tomorrow I am going to whack on a small sanding / file attachment (there are many available) and file both the inside and outside that way. The curviture of the blade is irrelevant. Hows that???

John

[Luke308]

Thanks again Jester

I had come across people talking of using dremmels for sharpening. And I have personally used one for sharpening my shovel in my attempt to learn how to use it to sharpen with a dremmel. The only thing I noticed was it was very easy for the dremmel bit to "grab" and go where it is not needed. The only way I can see around this (which I probably should have done in the first place) is to use a vice to clamp the tool being sharpened which allows two hands to securely control the dremmel.

I did get a nice sharp shovel edge, but it wasn't the same consistent edge the whole way across. Using it on something smaller like a knob cutter would minimise this of course, but I would hate to ruin some good quality tools by mistake. Maybe I will try it with my cheap Chinese tools that I am replacing and see how it goes??

Luke

[Tony Bebb]

Bonsai tools are not like sharpening a knife, and should not be sharpened on both sides of the blade. Like a chisel, only the angled side needs to be sharpened. Kawazumi Masakuni, of Masakuni Tools, was in Australia some time in the late 90's, and we had the pleasure of having him visit the BSQ Inc and give us a demo of how to sharpen tools.

Secateurs are the obvious one, with the angled side being sharpened in a circular or figure 8 action with a fine grade stone. After sharpening you simply close the blades slowly to remove the slight bur from the inside. If you use a stone on the inside flat surface, you will affect the way they meet and cut. Branch Cutters and Knob Cutters only need to be sharpened on the outside of the underrcutting blade, as this blade cuts in a scissor action against the inside face of the outside blade. Once again in a circular or figure 8 action. Occasionally you can run the stone over the outside of the outside blade to maintain an edge on it. You should not need to run a stone over the inside of either blade at any time.

I have sharpened my tools for many years in this method with an Ezi-Lap diamond sharpener in the fine grade, and is used dry. These cost around $25. The rust and sap remover is best used wet, and is very effective. Wipe the blades off and give a light spray with WD40 or RP7 for the black steel tools, and then wipe off the excess.

Tony

[Jester]

Yep, and like you said, putting it in a vice could help as well. The thing I regretted to mention is that with my Dremmel, I have the extension tool which is a bit like a fat pen. I don't know if you've seen it but it's like a kind of dentist's tool and gives you far more control.

Like you said though practice on some thing other than your best pair of knob cutters but I'm sure it will be easier than you think.

John

[Jester]

Just a quick note on the choice of lubricants there Tony ( and I take on board what you say on sharpening), rather than usind WD40 or RP7 , try using Lanotec in a spray. It is available from Supercheap Auto but does not have the toxic smell of it's counterparts. It is made from sheep's wool.

[harry]

Yep, and like you said, putting it in a vice could help as well. The thing I regretted to mention is that with my Dremmel, I have the extension tool which is a bit like a fat pen. I don't know if you've seen it but it's like a kind of dentist's tool and gives you far more control.

Like you said though practice on some thing other than your best pair of knob cutters but I'm sure it will be easier than you think.

John

Jester its called a flexi shaft, it is a lot easier with that, there are also a diamond fish hook sharpener, it is curved at one side and has a groove for the fish hooks, that will take the burrs off the inside of the branch and knob cutters,

keeping your tools clean will lessen the amount of sharpening needed, and as tony has pointed out the angle of the cutting edge is important

harry

[cre8ivbonsai]

Just thought I'd add KANESHIN Crean Mate to the mix for cleaning maintenance (not sharpening). This is best method/product I've found to remove sap or rust from cutting tools, a rubberized block with slight grit, it removes gunk and build up easily, reducing the frequency needed for sharpening.

Just my to add to the wealth experience above.

Cheers,
Ryan

[Pup]

Just thought I'd add KANESHIN Crean Mate to the mix for cleaning maintenance (not sharpening). This is best method/product I've found to remove sap or rust from cutting tools, a rubberized block with slight grit, it removes gunk and build up easily, reducing the frequency needed for sharpening.

Just my to add to the wealth experience above.

Cheers,
Ryan

No tool kit should be without one.

Pup

[Jester]

I could'nt agree more with Ryan and Pup's comments, in fact I would go so far as to say that for me, it is the best tool in my toolkit. What a lot of people don't know is that it is also excellent for removing gunk and scuff marks from glazed pots.

John

[Tony Bebb]

Ditto on the Crean Mate mates. It is the rust and sap remover that I use. It's the only one I have ever had.

Tony

[Luke308]

Found this whilst looking at the site recommended by Krittas (here - viewtopic.php?f=27&t=12543 )
Interesting concept
https://www.sidiao.com/index_e.htm