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I'm seeing quite a bit of water pooling on my work surface when I use the diamond wheels. I'm being careful to use only enough water to get good coverage of the wheel's surface, which is well below the maximum fill line, but water spills anyway.

It's almost as if the diamond wheel, when mounted on the T-8, puts water in places where the standard SG-250 wheel does not -- and those places do not drain into the trough, but drain onto the work surface.

Has anyone else seen similar behavior?

The composite honing wheel which is shipped with the new T-2 system requires no honing compound, as the abrasive is integrated into the material of the wheel.

I'd love to have an effective honing wheel which requires no maintenance, but Tormek currently has no plans to offer such a product for the T-8.

If anyone else shares my desire for such a product, please tell Tormek at support@tormek.se. I'm hopeful that if enough Tormek enthusiasts express interest, such a product would be brought to market.

[Results:]

This experiment was intended to learn more about the three systems I have at hand for honing on the Tormek leather wheel:

(1) Freehand: This involves holding the blade to the wheel using only my senses to judge the angle. I adjust the angle so as to minimize vibration and sound, as happens when the edge face is making smooth contact with the surface of the honing wheel.

(2) Laser-guided: This is also freehand, but with the assistance of a visible laser guideline on the honing wheel.

(3) Jig-guided: This is using wootz' excellent Front Vertical Bracket (FVB) in combination with the SVM-45 jig and wootz' FVB applet.

I used three new samples of a cheap kitchen knife. The protocol to create a test edge on each knife was:

• Mount the blade in the SVM-45 knife sharpening jig.
• Mount the SG-250 standard wheel.
• Set the USB height using wootz' applet.
• Create an edge using the SG-250 standard wheel at 220 grit.
• Mount the DE-250 extra-fine diamond wheel.
• Set the USB height using wootz' applet.
• Refine the edge using the DE-250 extra-fine diamond wheel.

I chose to use the DE-250 to refine the edge, instead of using the SG-250 graded to 1000 grit, because I'm looking for ways to speed up my sharpening workflow. I find grading the stone takes considerably longer than switching to a new stone.

Results: None of the trials resulted in very good BESS values; microscopy shows why.

Honing freehand appears to have polished the entire edge face evenly, with some rounding at the shoulder and some rounding at the apex. Residual burr is visible:



Honing using a laser-projected guideline appears to have been done at too steep an angle. The shoulder appears untouched, the edge near the shoulder appears untouched, and there is significant rounding of the apex. The rounding of the apex creates a reflective surface whose glare obscures good visibility of the amount of residual burr:



Honing using the FVB appears to have polished the entire edge face evenly, with some rounding at the shoulder and just a bit of rounding at the apex. Residual burr is visible:



Discussion:

The presence of residual burr on the FVB sample is of most interest, as this technique is known to produce near-ideal results in combination with the SG-250. Procedural error is certainly possible, in the form of inexact measurements, inexact USB settings, sub-optimal manual control of the blade in contact with the wheel, etc.

Having taken care with the measurements and settings, and having enough experience with the SVM-45 jig to be reasonably confident in my manual technique, I am tempted to look for other possible reasons for the presence of residual burr after FVB honing. Possibilities which will be investigated with follow-up testing include:

(a) The steel used in the cheap knives is pathological, and forms burrs which defy normal de-burring technique.

(b) The burr formed by the DE-250 diamond wheel is intrinsically more difficult to remove than the burr formed by the SG-250 standard wheel at 1000 grit.

I sharpened a Kyocera ceramic chef's knife using the Extra Fine diamond wheel. I matched the factory edge angle of 25 degrees per side.

It required only three slow passes with very light pressure on each side to replace the entire factory edge with a new, clean, uniform edge. Although there was no burr, of course, the difference in scratch patterns between the factory edge and the Tormek's edge made it easy to see when I had removed enough material to form a new apex.

While the new knife edge looks great cosmetically, it is not very sharp. It measures c. 600 BESS, and it cuts printer paper with difficulty. To understand why the cutting performance is not good, I examined the edge under a microscope.

This image shows the edge at 200X magnification. On the left is the appearance under top lighting only, and on the right is the appearance when side lighting is added.



This focus-stacked image shows the appearance of the apex edge-on:



Based on this microscopic examination, I believe the edge is not sharp because micro-chipping has caused the apex to be rough and broad. I'm open to ideas on how to get a finer edge.

[Materials needed:]

For your budget-conscious precision honing needs, I present the DIY Laser Honing Guide, a.k.a. DILAHON.

Materials needed:

(1) A line laser diode module, like this one available at https://www.adafruit.com/product/1057



(2) A 3xAAA battery holder, like this one available at https://www.adafruit.com/product/3287:



(3) A gooseneck stand, as is used in this IKEA JANSJÖ desk lamp:



(4) Tape

(5) A paper print of the attached PDF

(6) Electronics solder

(7) narrow shrink-wrap tubing

(8) 3 AA alkaline batteries

Tools needed:

(1) Soldering iron

(2) Heat gun (or hair dryer)

(3) Scissors

How to build the DILAHON:

(1) If necessary, cut off any existing connector on the wires of the battery holder, and strip the insulation from 5 mm of the ends of the wires.

(2) Slip a 25 mm length of heat-shrink tubing onto each wire of the battery holder.

(3) Solder the wires of the battery holder to the leads of the laser diode module.

(4) On one wire of the battery holder, position the heat-shrink tubing over the solder joint, then use the heat gun to shrink the tubing in place over the solder joint.

(5) Repeat step (4), above, for the other wire of the battery holder.

(6) Load the 3 AA batteries into the battery holder.

(7) Using tape, affix the laser module to the end of the goosneck stand:



(8) Print out the attached PDF, and cut it into a circle.

How to use the DILAHON:

(1) Affix the circular angle guide to the leather honing wheel, with the 0 angle line oriented vertically:



(2) Turn on the DILAHON laser, and position it so that the projected laser line falls on the leather honing wheel at the desired position. Here the laser line is positioned for 12 degrees:



(3) Remove the circular angle guide:



(4) With the knife blade kept horizontal (parallel to the ground for both roll and pitch,) position the knife edge at the laser line on the honing wheel.

(5) While keeping the knife edge at the laser line and keeping the knife blade horizontal, hone as usual.

This method takes advantage of our ability to judge and maintain horizontals and verticals with greater precision than we can judge or maintain arbitrary intermediate angles.

My typical results from unaided freehand honing are BESS values between 150 and 200. My first attempt using the DILAHON resulted in individual BESS measurements of 80, 108, and 110 (mean = 99.)

UPDATE: My latest test of the DILAHON resulted in individual BESS measurements of 73, 81, and 90, for a mean value of 81 -- a personal best.

Tormek recommends not using the leather honing wheel after using the SJ-250. In my initial results, I'm seeing a moderate burr, and a BESS score higher than I can get with proper use of the leather honing wheel.

Are there special techniques that should be used with the SJ-250 to get an edge which requires no honing?

This Cold Steel folding knife has a blade made of CTS XHP, and was sharpened at 12 dps on the SG-250/220, SG-250/1000, and SJ-250:

Is there a method by which one can hone knives on the standard leather honing wheel while maintaining precise control over the honing angle?

I haven't yet found any configuration of jig and USB which will allow me to hold a constant 12-degree angle between a blade and the leather wheel.

This is a burr from the SG-250 graded to 1000, used on a fixed-blade Mora:



The SG-250 graded to 220 yields this burr:



The DC-250 causes this burrpocalypse:



I can often get reasonable edges by using the SG-250 at 220 grit, and following it immediately with the leather honing wheel. I was hoping to use the DC-250 in a similar fashion, but so far the poor leather wheel hasn't been able to deal with Burrmageddon.

[Plan view:]

This is a blade from a specialized utility knife. To sharpen its entire length requires taking it out of its handle, which prevents using the SVM-00.

Which jig would be best to sharpen this blade?

TIA,
Tony

Plan view:



Side view:

Email exchange with Support at Tormek:

(1) I plan to switch between using the DC-250 and the SG-250 several times in a single sharpening session. Is it OK to do so without changing the water in the trough? I understand the Anti-Corrosion Concentrate won't harm the SG-250; my concern is whether SG-250 particles in the water could affect the DC-250.

"There should not be a problem changing between the diamond wheels and the standard stone.
The particles from the stone that could cause any diamond wheel problem are so heavy that it drops to the bottom of the water trough."

(2) What is the limit on how long I can use a single trough of ACC-treated water? Does the ACC in the trough lose its effectiveness after extended sharpening because of interaction with metal particles in the water? Does the effectiveness of the ACC in the trough diminish over time, even without any sharpening being done?

"The anti-corrosion concentrate does not lose efficiency as long as there is water left in the tray.
The only thing that can cause a problem is If there is any biological material left in the water that can cause mould growth, there is no anti mould additive in the ACC-150."

Greetings from a new Tormek user in the USA.

I've had great experiences using the Work Sharp system (with its Blade Grinding Attachment) to get sharp edges on a variety of knives. However, I've learned that for such a system, the resulting angle is affected by blade thickness, in combination with other variables. This poses a challenge in matching an existing edge angle predictably -- hence my interest in the Tormek system.

I was surprised and delighted to see the depth of thought and analysis done by members of this forum in predicting Tormek results using geometric calculation. Kudos and thanks!

To ensure I correctly understood Jan's calculations https://www.dropbox.com/s/ypbtaxgycgoyls0/KENJIG_wheel_support_distance_1.xlsb?dl=1, I performed several sharpening trials using items intended to provide a good variation in apex angles:

• a small rectangular plate of O-1 tool steel
• a narrow strap tie of mild steel
• a Ganzo folding knife of 440C stainless steel
• a RaidOps fixed-blade knife of S30V stainless steel

The results were measured by making impressions of the sharpened profiles in a conforming medium, and measuring cross-sectional slices of that medium by microscopy:



The results showed near-perfect linear correlation between predicted values and measured values:



Of interest is the offset between predicted values and measured values. Does anyone have any ideas on why my results are consistently c. 3 degrees more obtuse than predicted?