After truing the SJ stone

[Ken S]

I have trued mine once, maybe twice, using the TT-50. I have not observed any problems. Of course, I have a VERY light touch with the truing tool.

I bought a Nagura stone on a forum recommendation (sorry, I don't remember whose recommendation). I have not used the SJ much and certainly do not consider myself either expert or experienced with it.

Ken

[Grizz]

How many who have an SJ wheel have trued it? 

I have one and use it as the final treatment before stropping on leather for all my knives now.  But I have never trued it.  I use a Nagura stone to clean it, which it needs frequently, I think more due to the black marker that I use for checking angles than due to use.  It is at 249mm.  It just feels like the truing stone is too coarse to use on it. 

Rick

My SJ-250 had the spots and tiny holes at about 249, since then they have completely disappeared starting about 246 or so. I use the rust erasers and the nagura stone to clean the wheel after each knife I sharpen. I do use the TT-50 after 7-8 knives, it gets a little out of round. I have never used the stone grader on the SJ. never seen where I would need to. the wheel is now at 241mm and still works like a new one.

[Ken S]

Useful post, Grizz.

Ken

[Grizz]

Useful post, Grizz.

Ken

Thanks Ken, I consistently get readings from 125-175 BESS using the SJ. maybe one of the reasons is keeping it clean. it does get black from each knife I sharpen, hence the cleaning after each knife.

[Grizz]

I might also add that, I don't change the water using the SJ until I'm done for the day. it builds up a good swarf and that is constantly running over the wheel. I think this helps the sharpening process with the SJ.

[RickKrung]

Thanks Ken, I consistently get readings from 125-175 BESS using the SJ. maybe one of the reasons is keeping it clean. it does get black from each knife I sharpen, hence the cleaning after each knife.

I get similar BESS readings from just using the SJ stone, sometimes into the low 200s.  I consistently get those readings down to 90 to 130 after stropping with leather (EOU's SharpPad). 

Rick

[Grizz]

yes Rick, after stropping I usually stop around 100. jus no need to get sharper, unless your playin with it to see how far down it will go. lol

[Ken S]

Rick and Grizz,

You guys have inspired me to try using my Sharp Pad on the next chisels I sharpen. The leather honing wheel works fine with the bevel (and chisel still in the jig). I like stropping the back with a flat surface. The Sharp Pad might be just the ticket.

Ken

[Grizz]

it does make a BIG difference

[wootz]

Tormek added the Japanese wheel years after the stone grader SP-650, it was never designed to work with SJ.
As many of forumers, I also started with Nagura, but then switched to #1000 diamond plate shown below



When have to use TT-50, I go VERY slowly at the wheel edges not to chip them.
Edge-trailing honing on SJ gives better sharpness than edge-leading.

Overall, the SJ is the best Japanese wheel of all I've tried.

[Grizz]

Wow Wootz, I just learned a lot from that paragraph. I have chipped the inside edge before. I will try the 1000 diamond to clean the SJ. I am assuming the plate in the jig goes over the top of the 1000 to give it support.

[Ken S]

Very informative post, Wootz.

It should not be surprising that the SJ Japanese wheel needs frequent attention. It is essentially a slow motor driven round Japanese water stone. The trade off for cutting speed is very frequent flattening is required. (Oilstones cut better with frequent dressing, although this is not generally known. For India stones, as well as waterstones a diamond flat plate works well.)

This is a situation when I wish Tormek would share more information. Wootz makes a good point. The stone grader was designed long before either the SJ or the SB. In fact, the stone grader was designed before either CBN or diamond came into general (non industrial) use. From Wootz' experience, I would surmise that the stone grader might not be the ideal tool with the SJ. If so, that is no disgrace. A good tool should perform its intended task well. Secondary tasks are only secondary.

I would not be surprised to see several interchangeable diamond grading stones. In skilled hands, the stone grader is not limited to just 220 and 1000 grit, coarse and fine, with the SG wheel. Some skilled knife sharpeners routinely set the SG to 600 grit with the stone grader. These grit numbers are admittedly approximate, however, that is not a problem. With interchangeable diamond "stone grader" I can see being able to get at least three or more grits from the SG.

The SJ And SB use different abrasive material. Tormek has never claimed that the SJ can be modified. I suspect that it is an excellent one grit wheel.

We are evolving. I have had good success using CBN wheels. (I am not the only forum member using them.) CBN wheels are primarily marketed to turners using high speed dry grinders. They perform this task very well. The Tormek wet grinder use is definitely a distant secondary market for CBN manufacturers. Some CBN wheels have voided warranties if used wet. My steel wheels work wet, but only if an anticorrosion solution is used with the water. Even then, I am careful to dry the wheel and oil the steel reducing bushing. I have found the 250mm Tormek diamond wheels, specifically designed for the Tormek, are a giant step forward.

I expect the SG wheel to remain the wheel of choice for the budget minded user who wants the versatility of the Tormek with only one grinding wheel. I expect the SJ to remain the final step for very particular users. I expect we will see new options for grading the stones.

I look forward to seeing these advances.

Ken

[cbwx34]

I have a question for some of you... what is the "wear rate" of the SJ stone, compared to your SG stone?

I've had good success maintaining the stone solely with a fine rust eraser... and the stone shows very little wear as a result.  I think of this stone like any other fine waterstone... it should last a very long time.  I know some of you sharpen a lot more than me... but your "wear rate" just seems high to me.  (My opinion... and why I'm asking.)... 

Tormek says about this stone... "Its unique composition gives this stone an extremely long life".  I wish Tormek would publish some "actual use" numbers... but doubt we'll see that.

Anyway, am curious what the comparison might be.

[Grizz]

very well said Ken. I hope your speculation is right. Although the new diamond wheels are suppose to be maintenance free, other than the water additive, I believe Tormek will eventually develop a diamond plate that is much better than the current grading stone for use with the SG,SB, and the SJ.

[Ken S]

I am planning to make some new Herman type small platforms. I will be making two or three from cutting down the platform of a scissors jig. While Herman's concept of being able to have the platform do double duty and still work with scissors is a commendable example of Yankee thrift, using the full size scissors platform brings  constraints. I think an attached diamond stone for dressing and cleaning would make a very useful dedicated jig. It would be very quick to use.

Ken