Honing Wheel LA-220 edge-rounding root cause

[Ken S]

Stig's post reminds me of a technique I learned from Ernie Conover many years ago. Ernie kept a very fine ceramic stone with his Tormek. In a long out of print video, Ernie demonstrated using the leather honing wheel to polish the bevel of a chisel. Then, instead of using the leather honing wheel freehand, he polished the back freehand on flat ceramic stone. As long as the chisel was carefully placed flat on the ceramic stone, no rounding would occur. By leaving the chisel in the jig, the sharpener could alternate between polishing the bevel and the back with both the accuracy of the jig and the solid support of the ceramic stone for the back.

I agree with Stig about the importance of practice. The careful use of jigs can speed up the process of edge mastery for those of us (including me) whose skill is developing. However, a jig is not a full substitute for focused practice. I have no doubt that very skilled Tormekers can produce a polished flat back with the round Tormek wheel. I can do it to a level I find adequate for most work. For demanding work, I still prefer the jig and ceramic stone method.

One of the intriguing aspects of sharpening is how really sharp keeps getting sharper. We have benefit of both Tormek's decades of experience, plus the ideas and experience of many members. When I first started with this forum, most of the topics were what we would call "frequently asked questions", generally answered in one reply by thee moderator, Jeff Farris. We still have and welcome those questions. We also have an emerging number of very interesting deeper topics, such as this topic. They are not (fortunately) one reply questions, but, rather, stimulating discussion topics for numerous members. We have several very able mathematicians and a reliable way to quantify sharpness measurements (BESS  readings).

I have long felt that current technique for flattening and polishing chisel backs was not the Tormek's strongest area. Nor have I felt that most users fully master the leather honing wheel. I look forward to advancements in these areas.

Ken

[Ken S]

Stig,

Your "really nerdy info" comment gave me a good belly laugh! I agree, however, I also recognize the value of really nerdy stuff.

I installed and repaired high speed data circuits. Factors which were not critical for dial up circuits could easily put a high speed fiber optic circuit out of service. Most people would consider the precision of atomic clocks overkill. If a parent is watching the clock to make sure the child gets on the school bus, atomic clocks are overkill. If the same parent deposits money at a bank, that deposit must go through fiber optic data circuits to the Federal Reserve. Those nerdy atomic clocks make this possible.

In the same way, really nerdy info can infiltrate into daily sharpening. The kenjig is essentially just a rectangular small piece of plywood. However, this simple appearance masks some high power nerdy trig, added by Dutchman's work. I do not know where this nerdy discussion will lead. I do believe that it will benefit the average user, just as the average family car owner has benefitted from the developments in auto racing.

Welcome nerds!

Ken

[cbwx34]

So, if I'm reading Stickan's post correctly, the difference was done intentionally, to create a microbevel, and/or insure the edge is being hit during honing?  (Just making sure I'm understanding it correctly).  If so, that could easily be addressed in the documentation.  (I agree with the concept... fwiw).

Also I noted two things on wootz post of the honing testing... he stated it doesn't apply to honing on the LA-220, and I guess we'll have to wait for the report to see if it could even be extrapolated to it.  But, (and call me skeptical)... that, based on Bessex chart, an edge can go from "razor blade" sharp to an edge defined as "moderately rolled"... "edge in need of maintenance or repair" based on a .2 deg. angle change in honing?  I'm not saying I doubt that's what the test may have shown... but for me, that raises many more questions. 

[Stickan]

Well, It's not a microbevel. Its a polished edge.
Now, with this said, using much pressure over a long time can change the angle slightly. But I doubt that this is the reason for the result using the Bess system.
I will be in England during the weekend at the European Woodworking show and will have limited time in front of the computer.
I will try to get time to answer questions once a day if I see that I need to "jump" in to the discussion.

Sincerely,
Stig

[wootz]

It is really encouraging to know that Tormek engineers' recommended honing angle for chisels of + 0.4-.5 degrees is in line with what we named the Best Honing Angle in our study for knives.
This study was accomplished for paper wheels at high RPM with 0.5 micron diamonds, which is pretty an aggressive honing compound, taking them closer to hard hones than the leather wheel - this explains quick worsening of the BESS score with further angle increase.
After it is published in the Sharpeners' Report, I will ask the editor's permission to publish here - if not allowed will send complimentary copies to Jan, Dutchman and who else asks, it is a digital magazine.

What I can't agree with, is the "nerd" label - calls not to overscience sharpening can only halt progress.

... Of coarse there is a difference with a knife and a chisel.
It would be very interesting to know how the knifes are honed. Is the result the same when using the knife jig or honing freehand?

Best,
Stig

I probably would have never stumbled over the 215/220 issue if honed knives freehand.
The problem revealed only because we use a frontal vertical base we designed for honing and computer software allowing to set honing angle with high precision, as described on our website
http://knifegrinders.com.au/11Shop_VB.htm
http://knifegrinders.com.au/05Equipment_scripts.htm

Though we normally hone on paper wheels, there are certain steels better worked on leather wheels, we have a set of them with honing compound of different grits.
And because we sharpen collector's blades to submicron level, < 70 BESS, a 1 degree discrepancy at the very edge apex is brutal, even 0.5 degree is with leather, and 0.2 with paper wheels.

[RichColvin]

Wootz,

I'd love a copy !

Kind regards,
Rich

[Stickan]

Wootz,

"What I can't agree with, is the "nerd" label - calls not to overscience sharpening can only halt progress."

I am sorry if you felt that I wrote this in a negative way. Its actually the opposite. When it comes to knifes I call myself and friends the same but with a positive tone.
The forum is a community with high understanding of Tormek and sharpening. English is not my born language and maybe nerd can only be used negatively? its time for a change if so.
Or come with an suggestion what we forum members can be called when we are going deeper in to details 

Sincerely,
Stig

[cbwx34]

Or come with an suggestion what we forum members can be called when we are going deeper in to details 

OCD?   

[RichColvin]

Stig,

I did not take it negatively.  Rather; I thought it was funnily true.

Kind regards,
Rich

[Ken S]

We all share a common passion for achieving sharp edges with the Tormek. I recall reading somewhere that early man used tools before he discovered fire. I would call that an ancient craft.

In the common pursuit of this passion, we are bound to have minor misunderstandings from time to time. Let us march on and let this unintended midunderstanding pass. Personally, I prefer to be in the company of dedicated, passionate friends to being part of a group of less interested members.

Ken

[wootz]

I think i owe an apology to Stig - it was a knee-jerk reaction of mine just because earlier that day someone said I overscience sharpening 

[cbwx34]

...because earlier that day someone said I overscience sharpening 

Compliment... as far as I'm concerned. 

I've learned tons from what you're doing, so.... keep 'oversciencing'!!!   

[SharpenADullWitt]

I think i owe an apology to Stig - it was a knee-jerk reaction of mine just because earlier that day someone said I overscience sharpening 

They say that until they need your help or something that you have learned.
That tends to be a failure on their part that science really only provides theories that are the best we know at the time, until something can be actually proven.  (like the Apollo Astronauts on the moon, with a feather and a hammer)

[ega]

Wootz,

"What I can't agree with, is the "nerd" label - calls not to overscience sharpening can only halt progress."

I am sorry if you felt that I wrote this in a negative way. Its actually the opposite. When it comes to knifes I call myself and friends the same but with a positive tone.
The forum is a community with high understanding of Tormek and sharpening. English is not my born language and maybe nerd can only be used negatively? its time for a change if so.
Or come with an suggestion what we forum members can be called when we are going deeper in to details 

Sincerely,
Stig

I am just off to measure my honing wheel but stopped to check the definitions of "nerd" and "geek" in my new Concise Oxford Dictionary; I commend the latter term so far as UK English is concerned - "a knowledgeable and obsessive enthusiast".