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Interestingly I was watching a video last night from a Japanese master craftsman who was talking about sharpening. He said that it was a mistake to take a knife to 10,000 or higher since it - as you say - removes the tooth from the knife and makes cutting thinks with an outer skin such as tomatoes harder.

Leave it. It dies not harm and trimming may damage the rubber if you slip.

Interesting discussion. The hardness of CBN and diamond is quite close and both are much harder than would you are sharpening so I don't think that this is really and issue. However the article linked here https://www.sciencedirect.com/topics/engineering/cubic-boron-nitride#:~:text=Abrasives%20and%20abrasive%20tools&text=The%20popularity%20of%20CBN%20is,grinding%20high%20quality%20tool%20steels.

indicates that "...Due to chemical–thermal degradation, CBN wears five times more rapidly than diamond..." when water cooled. This is due to the layer of boron oxide that is formed is water soluble. So maybe that is why some manufacturers do not recommend wet grinding for CBN.

To be brutally honest for most of us either is perfectly fine, depending on your requirements. My last diamond wheel I got $130 off the odds which made it nearly on par with the cheap Chinese CBN so a no brainer for me.

Darita,

In my opinion, the fastest, most repeatably accurate way to set up chisels (and plane blades) is with the Tormek TTS-100, shown in this link:

...

Ken

Just tried this and works a treat. I have a rule with a stop on it. I set each angle them measured the protrusion. Once I know that I can record it. To set up a blade for sharpening I simply set the stop on the rule then set the protrusion using that.

There may be a dag on the bore edge f the wheel. Take a small piece of sandpaper, probably 240 G and run it around the inside edge of the wheel. Definitely do NOT touch the shaft with anything other then lubricant!!!

I recently watched a sharpening video from Jonathon Katz-Moses here https://youtu.be/GBjiEmN5HzA and he was getting results in the 110-120 range after stropping. For 25 - 30 deg bevels this seems to be about right.

When sharpening chisels, should the SJ 250 be used trailing edge, turning away from the edge?

Tormek recommend sharening with the stone towards the edge. This produces a smaller burr apparently. With the jig secures ther eis no danger of digging into the stone.

I am not sure if it really makes any difference so long as each blade has an exactly straight edge. In most planners each blade height is set individually so that it does not matter if one blade is a fraction of a mm different in thickness. Of course there is the issue of an imbalanced cutter head but you would need quite a difference in width for that to make an impact. Obviously where you are using indexed blades such as those in bench top planners the width is far more important but then they use disposable blades.

For a clue about what may possibly be coming, study history:

https://www2.canadianwoodworking.com/tools/tormek-turns-40-unveils-sharpener

Ken

Exactly what I thought when I saw that

There could be a couple of things. If you are using consistently too much pressure then you can dig into the stone and any inconsistency can be exacerbated over time and cause undulation on the stone. Another possibility is that an inexperienced user may falter and cause the implement being sharpened to jump this causing an unevenness in the stone. Once you get a slight dip this will be amplified over time. One way to prevent this is to use the stone grader regularly. But Tormek help is your best bet.