Sharpening for chisels and planes

[Stewie Simpson]

The following shows the Sigma Power Hard Ceramic Stones after sharpening a W1 plane iron to 13000 grit.

Note; to achieve a fair and reasonable comparison on the resulting wear patterns on each grit stone, the removal of the wear bevel on the back of the iron, and re-establishing the flat primary bevel were both completed on a flat glass bed of #220 then #400 grit alum oxide sandpaper, prior to using the ceramic stones. The ceramic stones also received a full flattened with the diamond flattening stone prior to working the iron.






The ceramic stones then received a quick scrub before being marked with a pencil to highlight the level of flatness after working the top surface of each stone with the diamond flattening stone.

The final photo shows the results after 12 strokes of diamond flattening stone on each stone. #400, #1000, #6000, #13000.

[Jessica de Boer]

I have heard positive things about that Sigma 13000 stone but I wonder what kind of edge it produces compared to a natural stone? I've always found the edge a very high grit synthetic produces to be very transient but maybe this stone is different.

[Greg Parrish]

Stewie, thanks for the detailed info but I’m not sure how to take the results. I see that they didn’t completely flatten which shows stone wear, but I don’t have anything experience wise to compare that to. I’m assuming it is a sample of good stones, right? Also What flatten plate are you using?

Thank you very much. Please Keep sharing. I’ll start to put 2 and 2 together as I get more experience with stone sharpening.

[Robert Engel]

Take a look at this. Looks identical to a Trend

[Greg Parrish]

Hmmmm. Only difference I see is the trend doesn’t have the lines on the 1,000 side. Regardless I bookmarked it for later.

[Stewie Simpson]

Greg; the results confirm that the coarser grit stones within the Sigma Power range have a higher susceptibility to abrasive wear than their finer grit stones.

The diamond plate I am using is the Atoma #400.

Stewie;

[Brandon Speaks]

As long as it has a hard backing to keep it from flexing too much it will work just fine. I generally just buy leather scraps and glue them to a piece of wood.

Yes the flexcut is fine. When I bought my pinewood forge strop for my carving tools I moved my flexcut to my sharpening station for chisels and planes. Their compound is a little hard for my taste and I have to warm it up a little to get it to apply how I want. I still use it though.

[Stewie Simpson]

I have heard positive things about that Sigma 13000 stone but I wonder what kind of edge it produces compared to a natural stone? I've always found the edge a very high grit synthetic produces to be very transient but maybe this stone is different.

Jessica; below are the specs supplied by Stu on the #13000 Sigma Power stone.


Sigma power ceramic stone #13000 (no base)

Sigma Power ceramic stones are not easily found outside Japan, but that does not mean they do not have an enviable reputation around the world for being something 'above average'.

Designed for sharpening blades of greater tenacity than standard carbon-steel alloys, they remove metal rapidly while staying relatively flat and dish free.

This #13,000 grit stone measures 205x75x25mm and is supplied without a base.

[Phil Mueller]

Thank you Stewie for all the info (and time!) you have provided on this thread. Very informative.

[Vincent Tai]

I have heard positive things about that Sigma 13000 stone but I wonder what kind of edge it produces compared to a natural stone? I've always found the edge a very high grit synthetic produces to be very transient but maybe this stone is different.

Very nice durable edge. Though I've never had a problem with edge life off any high grit synthetic. the Sigma 13000 is definitely one of my favourites along with my two Jnat finish stones. The Lee Valley Sigma 13000 Power Select II ceramic is the same as the Sigma 13000 Power ceramic stone you can get on Stu's site, if you take a look the 13000 is the same for both available lines on Stu's site. Might be faster getting it from LV. The edge off of the 13000 is very nice to feel. It is a fast finisher and even though I've used mine plenty and for a few years I still have a good bit of stone left. If you lose control of your tool and dig it in or raise it and dig it in the stone can be gouged. I've had nothing disastrous happen in terms of that and I suspect it will be hard to do more than minor annoyance and cosmetic damage. The Shapton equivalents are a lot harder but the Sigma 13000 is my preference. The softness has not bothered me even with my appreciation for my very hard Ozuku.

[glenn bradley]

Hmmmm. Only difference I see is the trend doesn’t have the lines on the 1,000 side. Regardless I bookmarked it for later.

The only thing I can add is my experience. I have not had a Trend diamond product last for beans when compared to DMT products I have that have lasted years. All of my Trend products either wore out or were returned. Your mileage may vary.

[Jessica de Boer]

I found the 13000 on global rakuten for just €67,50, that's cheaper than toolsfromjapan or Lee Valley. I might just order it for that price.

@Vincent Tai: Do you use it to sharpen Japanese blades? What kind of finish does it produce, it is highly polished or is there a nice contrast between the hard and soft steel?

[Vincent Tai]

I found the 13000 on global rakuten for just €67,50, that's cheaper than toolsfromjapan or Lee Valley. I might just order it for that price.

@Vincent Tai: Do you use it to sharpen Japanese blades? What kind of finish does it produce, it is highly polished or is there a nice contrast between the hard and soft steel?

I do often use it on Japanese blades, laminated blades. It is an interesting stone for these laminated tools, at first there is an almost kasumi type finish; the hagane is mirror polished but the jigane is contrasted, the abrasive seems aggressive enough to just cut the jigane differently. I often go through a couple or three synthetic stones quickly ending with the Sigma 13000 (touch ups) when mortising for a long time with Japanese chisels and I can clearly see the definition of the lamination. Natural stones have it beat out by far though. But if you spend enough time on the stone then it will polish up the whole bevel and produce that garish look. Often if you are sharpening up a kanna for the finish planing you can see the jigane just transitioning into the mirror polish stage. I woke up this morning and stumbled down into my shop to get a couple chisels ready and having read your questions I decided to see how long it would take for the 13000 abrasives to break down and polish the jigane; a couple minutes later I could still see the lamination somewhat but it was a pretty garish sight. Very polished. However it was sharp enough for any task a couple minutes earlier without the excess polishing and without the garishness. I think on tools with bigger bevels (Kiridashi) it might be hard to avoid the polish. I suppose the speed at which it does its work makes up for the possibility of excess polish in a laminated tool, and the speed also prevents over polish if you catch yourself.

Jessica, can you share that global rakuten link somehow? If the forum doesn't allow a link in the thread I would very much appreciate a PM with the link, my Google fu is no match for this site. At that price I might snap up a couple at the end of the year and be set for a while. I'll inevitably have to scratch the itch and get many more stones in the upcoming years but I really like the sigma 13000.

Thanks,

Vince

[Jessica de Boer]

I will post the link here and we'll see what the admins want to do.
https://global.rakuten.com/en/store/..._en_rvp_widget
I'm lucky because I know someone in Japan who can buy it for me and then send it to me. If you're not so lucky you would have to use a forwarding service or proxy buyer and that will probably negate the price difference.

[Chris Parks]

It may surprise some but a lot of Japanese don't use stones at all but Silicon Carborundum Powder on a metal substrate, there are some YT videos showing this and a friend of mine recently did a course where he was shown this method so I decided to have a play and see what happens. I do my sharpening free hand so if you use a jig you might find this method a bit difficult to deal with.

I obtained an old worn brake rotor from a car, it is cast iron, cost nothing and my son happens to have a brake lathe at his work so he machined it for me both sides. I then hollow ground a few blades on a 180 CBN wheel and using some 240 powder wet it into a paste, water, oil, light grease whatever you fancy will do for that. The beauty of this system is it is progressive in grit size as you work, it starts at 240 or whatever powder is chosen and as you continue to sharpen it breaks down to a finer grit the more you keep going and you can hear it happening. You want a 20,000 finish, just keep sharpening and that is what you get. My friend was told to keep at it until the powder turned white and then instantly stop but he was using water where I used some oil so I don't know if the same criteria works.

After I thought I had taken it far enough I stropped using green compound on a piece of MDF and it certainly is at least as sharp as any of my previous methods and I do use Stu's three stones or some Shapton glass stones to compare it to. Total cost was less than five dollars including the fuel to pick up the rotors and no mucking around with progressive stone grits into the bargain. I will pre mix some powder/oil so as to speed things up a little. I can't think of another way to sharpen a blade for less money and less mucking around.