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[I experienced a consistent difference of 1 degree that the KS-123 is below the reading of my laser instrument]

Hello everyone, I am new to the forum. I have been using T8 since 2020 with standard, CBN and diamond wheels, mostly on 8" kitchen knives and a little less on my folder collection. I was so happy when KS-123 came out because of the time economy compared to the Edding/sharpie method. I check my angles before and after sharpening with a laser goniometer. I experienced a consistent difference of 1 degree that the KS-123 is below the reading of my laser instrument. Can anybody in this forum confirm that difference by his own experience?

When I use the KS-123 and compare the ground edge to my laser goniometer, I do not see such a discrepancy.  

[Capillary suction (Laplace pressure)]

I believe there is a solution if you have a metal lathe. 

I asked Claude (an AI),

Capillary adhesion is experienced between the grindstone and the washer on a Tormek grinder. If the washer had most of the surface dished out (as if it were a bowl), would this surface adhesion become almost negligible?

The response was,

Yes, and quite significantly — for two separate reasons tied to the two mechanisms:

Capillary suction (Laplace pressure)
This force is roughly proportional to the contact area where the thin film exists. Dish out the center and that area shrinks to just the outer rim, so the suction force drops proportionally to how much area you've removed.

Stefan (viscous squeeze-film) adhesion
This is the bigger effect for a fast pull-apart, and it's the one that benefits most dramatically. The Stefan equation says resistance scales with the fourth power of the radial distance water has to travel to escape:

F ∝ R⁴ / h³

That R⁴ term exists because water at the center of a flat disk has to travel the full radius outward to escape when the plates squeeze together — a long, slow path. If you dish out the center, that water is sitting in an open reservoir with nowhere to build pressure — it's not trapped. Only the water in the thin rim band actually gets squeezed, and it only has to travel the width of that rim (not the full radius) to escape. Since the effective flow-path length drops so much, and the force depends on that length to the 4th power, the reduction is dramatic — often far more than proportional to the area removed.



Net effect: You wouldn't make it perfectly zero — there's still a wetted rim doing some work — but you'd cut both the suction and (especially) the "stuck fast" viscous resistance dramatically. This is essentially why things like vacuum-cup release valves, dimpled/grooved plates, and relief channels are common tricks for beating stiction — you're shortening the escape path for the trapped film rather than trying to eliminate the film itself.


You could test this premise using a 3d printed part. 

Paul's drip tray is excellent.  

As for hanging the grindstones, I'm not keen on that for the traditional style ones (SG, SB, & SJ).  I designed these to store them standing up (https://sharpeninghandbook.info/Jigs-GrindstoneStand.html), and they work well..

Gerd,

Thank you!

Rich

MBS,

I am a woodturner with this setup:

* https://sharpeninghandbook.info/Images/ForumPics/TormekStationFront.jpeg
* https://sharpeninghandbook.info/Images/ForumPics/TormekStationSide.jpeg

(I can't imbed the pictures for some reason, but the links work.)

The toolbox on which my Tormek T-8 sits is 32" tall.  I am 5'-7" tall; you may need to adjust the height of the stand to match your height.

I have found that I grind my turning tools with the grinding wheel rotating towards me (as shown in these pictures).  Thusly, I am looking down at tools which are often held in a more vertical position.  This height works well for that.

Also, having this on a toolbox makes for storing the jigs easy, and keeps them right-at-hand for quick use.


As you are getting started using the Tormek for sharpening wood turning tools, I recommend you take a look at the Time Saving Tips I've cataloged at https://sharpeninghandbook.info/TimeSavingTipsForTheTormek.html.  These really make it easy to quickly re-sharpen your tools and get back to woodturning.

Rich

My experience has been that:

• The paper wheels make a very shiny edge, but
• The Tormek leather stropping wheel provides a sharper and longer lasting edge. 

I've not seen any analysis on this, so I am wondering what others are finding.

I've created some 3D-printable grindstone stands to allow them to be easily stored vertically.  The designs are available at the Sharpening Handbook (https://sharpeninghandbook.info/Jigs-GrindstoneStand.html).

My gut feeling is that this is a better way to store the grindstones than by hanging them by their arbor on a peg (I just feel that aligning the grindstone's opening with the peg will wear on the opening).

I was recently using my SuperGrind 2003 which has been upgraded to use the stainless steel shaft with an EzyLock nut. The nut was well locked in place, holding the SG-250 quite tightly, and it took extra tools to remove the nut. 

As I dove into the screw threads to figure out how the nut got stuck, I found it was rather full of some gunk. It was easy enough to clean up, but it does bring me to a thought about a best practice. 

I already lower the water trough, but going forward I will also be sure the nut is removed or at least loosened.

Bruce, what did you end up doing?

What about using the MB-102 Multi-Base with the KJ-45?  Then, as noted by Rick, the side of the grinding wheel can be used.

You should try:  The SVD-110 Tool Rest would probably work well.  If not, a platform jig (https://sharpeninghandbook.info/Jigs-Platform.html) may be useful.

[Primary facets]

Dan Heil developed a set of templates which make setting up the DBS-22 a lot easier when addressing the secondary grind.  And, he added the capability for a tertiary grind as well.

There are separate templates for each clearance angle.  Below are pictures of the one for 9° in use.

Primary facets


Secondary facets


Tertiary facets


These are based on these calculations:

• secondary facet angle = primary facet angle + 13°, and
• tertiary facet angle = secondary facet angle + 32°.

The great value to this approach is the ease in setting the secondary (and tertiary) facets in a very repeatable manner. Additionally, it is easier and faster to use this method than the approach outlined in the DBS-22 user manual (pg. 11).This really comes into play when resharpening a number of drills at one time.


The files to 3D print these are at 

• https://sharpeninghandbook.info/Jigs-DBS22-Setting-Templates.html, or 
• https://www.thingiverse.com/thing:7365248.

When I hear concerns about using the KS-123 due to it being less than needed accuracy, I wonder why the angle on the blade must be accurate to 0.1°.  In the sharpening I do for most things, if the angle is good to +/- 1 degree I am good.  What am I missing?

The SE-77 may also be misaligned.  That is what prompted me to develop an alignment jig for it https://sharpeninghandbook.info/Jigs-SE-77-Alignment.html.  You can easily 3d print one for yourself. 

No, but you will certainly spill water, & get dripping off the tools you are sharpening.