Thread: Tragedy and the shattered Shapton

Originally Posted by LanceC

Can anyone offer creative uses for a broken polishing stone?

Lance

That's an expensive drop.

You can sharpen your axes with the larger pieces hand held. Use a circular motion.

Regards
Paul

Lance, that's devastating. I don't know how you sharpen / hone, but you should have enough room on the big pieces to hone on the flats of a concave grind. I tend to use short strokes anyway. But think on the bright side, you now have a good excuse to buy more gear.

Cheers,
Zac.

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Originally Posted by Bushmiller

That's an expensive drop.

You can sharpen your axes with the larger pieces hand held. Use a circular motion.

Yes it was. It took me over a year after buying my DMTs to work up the courage to spend another $100 on my sharpening setup. At least back then part of the procrastination was due to not being convinced that polishing at 8,000+ after 1,000 was worthwhile. Unfortunately now I know what a joy a polished edge is to use, so will need to replace it sooner rather than later.

With respect to axes, I only own one axe head, and it doesn't have a handle attached to it at the moment. At least now I can own a sharp axe head without a handle attached to it.

Originally Posted by Fergiz01

Lance, that's devastating. I don't know how you sharpen / hone, but you should have enough room on the big pieces to hone on the flats of a concave grind. I tend to use short strokes anyway. But think on the bright side, you now have a good excuse to buy more gear.

Yes, I sharpen like that too, so in all likelihood I could make it work. An unexpected advantage of not using a jig. The larger surface does allow for more use before needing to flatten the stone however. On the bright side it will flatten with less effort now.

Sadly, replacing something that performed well with the same, doesn't quite offer the satisfaction of getting something new.

Originally Posted by LanceC

20210706_100351.jpg


Can anyone offer creative uses for a broken polishing stone?

I'm not sure about a creative use, but you still have three usable pieces of stone there Lance.

The smallest piece can be used as nagura to raise slurry on a #12,000 stone, which is far less aggressive than a diamond plate used for that purpose.

The larger piece is still very usable as a sharpening stone at that length. Half the length of a normal length stone is more than sufficient to get the job done. As you are already using shorter strokes that shouldn't be an issue for you, and furthermore, that is a good practice IMO, as longer strokes exacerbates the shoulder pivot and elbow lift problem.

Anyways, some of my stones came at that length... and are highly sought after.

IMG_2493.jpg
Oohira suita

And, the other piece you can use for smaller blades.

If securing the irregular end/s is an issue, just glue onto a square piece of wood.

I have glued stones back together that have cracked in two using CA, but you do need all the pieces to go back together with a close fit and also a good CA that copes with the water.

Originally Posted by NeilS

I'm not sure about a creative use, but you still have three usable pieces of stone there Lance.

Thanks for a very informative post Neil. I think I will take your advice on all points. The first order of business will be to glue the larger pieces to backing boards. Can you offer any suggestions on what to use as an adhesive?

Originally Posted by LanceC

Can you offer any suggestions on what to use as an adhesive?

I've successfully used gutter grade silicone.

Keep it thin on the base of the stone so that it doesn't become a bouncy pad and a bead around the outside bottom edges to resist any sideways movement. It takes a few days to cure, depending on the density of the wood you have chosen for the base. I used western red cedar myself because it's light and seemed to allow the silicone to cure a bit quicker.

I used silicone rather than epoxy because the wood will expand and contract with being wet then dry and the silicone has enough flex to accommodate that.

Can you not dry them out and glue them back together? If you nominate one side to be the the only one for honing you should be able to glue up the shattered faces up to about 1/4" of the honing face; that way you won't get a glue line on the surface until it's been worn down that far. Use a diamond stone to flatten the honing face and that should do. Or maybe glue them DOWN onto another flat surface using polyurethane adhesive before dressing the surface?

Originally Posted by LanceC

20210706_100351.jpg

I know it shouldn't bother me as much as it does, but boy did this put a dampener on my evening. The 12,000 no longer refers only to the Shapton's grit.

Can anyone offer creative uses for a broken polishing stone?

I understand that the pieces of your 12,000 stone can be glued back together using plate glass as a substrate. I'm sure that Derek was forced to do this 15 or so years ago with a stone he purchased from an O/S ebay seller -- but a quick review of his site didn't turn up a reference.
I don't know if CA is waterproof, but a UV setting glue (as advertised on you tube and elsewhere) definitely would be waterproof. (UV setting glues are used to repair teeth.)

RTV silicone. It is both waterproof and a little bit elastic.
Talk to wood carvers, those stone pieces are plenty big enough to put the finishing edge on palm tools and also gravers.

Originally Posted by NeilS

And, the other piece you can use for smaller blades.

Or... cut it up into three or four pieces and sell off as #12k nagura at $25-$30 a pop...

Quality Naniwa #8000 Grit Japanese Nagura Stone Suitable King KW-65 Whetstone | eBay

Originally Posted by NeilS

As you are already using shorter strokes that shouldn't be an issue for you, and furthermore, that is a good practice IMO, as longer strokes exacerbates the shoulder pivot and elbow lift problem.

Freehand sharpeners like Lance and Zac are already aware of the following, but there may be others who may not.

Here is a video showing how traditionally trained Japanese sharpen a chisel using short strokes.

The video is primarily about the importance of flattening a stone for chisel sharpening, so there is a very great deal of that in the video, but it also has some good segments on how they use short strokes to sharpen.

If you want the very short sped up fast forward version, see the 30secs at 7:30 -> 8:00

To see that in real time (note the finger position) see the next 30secs at 8:00 -> 8:30

And, highlighted by looking at it in another way, see the areas on the stone that have been used between 13:15 -> 13:45

宮大工が職人技で教える初心者のための”のみ”の研ぎ方はこれだ！　Sharpening a Japanese Chisel - YouTube

The rule of thumb is that the length of stroke is about 3x the width of the chisel.

Wider straight blades, like kanna/plane blades, are usually held on the oblique and don't need quite the same multiple of travel.

The point being, if you are freehand sharpening and not needing a lot of runway for a sharpening jig, smaller pieces of stone are still useful and can do a very good job.

Originally Posted by ian

I understand that the pieces of your 12,000 stone can be glued back together using plate glass as a substrate. I'm sure that Derek was forced to do this 15 or so years ago with a stone he purchased from an O/S ebay seller -- but a quick review of his site didn't turn up a reference.
I don't know if CA is waterproof, but a UV setting glue (as advertised on you tube and elsewhere) definitely would be waterproof. (UV setting glues are used to repair teeth.)

Ian has a good memory. Here is an 8000 Shapton Pro on glass ...



I used two-part epoxy, probably the 15-minute type. It worked so well that the bond has remained to this day.

I have also epoxied together natural stones. The thin epoxy layer does not appear to cause any issues. The thought occurs to me that, if you have voids after glueing, fill them by sanding down the stone while it is dry, and using the "dust" with a little epoxy as a filler.

Regards from Perth

Derek

I've used CA to glue the following stone back together. You can just see the glue line after flattening again with diamond plate. The glue line is just visible and makes no difference to anything that I can see/feel.

Hakka stone CA mend.jpg
Hakka tomae

There is mixed information on whether CA is waterproof. So far it has held together, but keep in mind that I don't store my stones wet. The CA was a quality product (like Hot Stuff) that I buy for woodturning, so that may make a difference.

Lance,

Maybe an el cheapo high density plastic chopping board cut to size could do the trick as a backing?

Cheers,
Yvan