Introduicing The KenJig Video Calculator...

[cbwx34]

I know that some people (cough...Ken...cough) have a slight aversion to computers, but like watching videos.

So introducing the KenJig Video Calculator - Revised... a video that can be watched and used to help build a KenJig.   

Based on the original formula (sorry Jan), to keep things simple and consistent as the original. 

Enjoy!

Edit 7/12/20:  While I made this with a bit of humor, I've now modified it to show both the Original and New Formula results.  (Same accuracy because... rounding).

How to make a KenJig can be found HERE.


   

[Ken S]

Thanks for thinking of me, CB. I am really not as competer adverse as you might think.

Using your illustration as a starting point. If we set the Projection and Distance as shown, and maintain a standard bevel angle, everything will be preset for the next knife or fifteen knives, with or without a computer. The wheel diameter will gradually diminish with use, however, for most of us this will occur very gradually.

For the record, I set up the kenjig using Dutchman's original tables. When I need to calculate a new kenjig, such as to sharpen my Chinese vegetable cleaver, I either refer back to Dutchman's original tables or use your Calcapp. (Dutchman's newest tables require a computer program I do not have.)

Ken

[Jan]

CB,

I suggest you publish it as a book. The title of the folding concertina book may be KenJig Calculator in Images by C.B. It would make me happy if you add a disclaimer that the maximum absolute error is 1 mm because the original formula was used. 

Even better idea may be to join forces with Ken and prepare concertina booklet "How to Build  a KenJig". KenJigs for different set up parameters could be printed as jigsaw puzzles.

Jan

[cbwx34]

...I either refer back to Dutchman's original tables or use your Calcapp. (Dutchman's newest tables require a computer program I do not have.)
...

Calcapp is based on the new formula.

...
It would make me happy if you add a disclaimer that the maximum absolute error is 1 mm because the original formula was used. 
...

I added "Accuracy +- 1mm" in the video's description.
(Which is within a degree...).

[micha]

Even better idea may be to join forces with Ken and prepare concertina booklet "How to Build  a KenJig". KenJigs for different set up parameters could be printed as jigsaw puzzles.

Jan

As much as I enjoyed the video, I shall be waiting for the musical... 

[OrangeBeachReb]

I'm dealing with a wife with cancer and chronic disease. She just got out of the hospital.  I say this with sincere affection: You all are such geeks! I love you for it!  I am one too!  I have three daughters and I think it's bizarre I'm into knife sharpening all of a sudden.   

This is an incredible escape for me. Don't change. 

I just bought the T4 and I have messed up some and I cut my finger once. However, I love the passion here and I love the escape.  Carry on!

Thanks..... Chris

[cbwx34]

...
It would make me happy if you add a disclaimer that the maximum absolute error is 1 mm because the original formula was used. 
...

While I made this with a bit of humor, I've now modified it to show both the Original and New Formula results.  (Same accuracy because... rounding, although, for practical purposes, it's fine).

KenJig Video Calculator - Revised

I also added a link to "How to Make a KenJig"

As much as I enjoyed the video, I shall be waiting for the musical... 

Still no music.   

[Ken S]

CB,

I'm waiting for the musical version. 

The kenjig has very humble, but sound origins. It was conceived by combining my adaptation of the TTS-100 and Dutchman's Grinding Angle Tables. I had been using a slightly modified TTS-100 to accurately and efficiently set up sharpening of my chisels and plane blades. I had learned the importance of the relatedness between Projection and Distance. When Dutchman posted his Grinding Angle Tables, I saw the benefit of replacing my initial trial and error setup with Dutchman's solid trig foundation. The kenjig just applied my Projection/Distance work with Dutchman's tables and adapted them to knife sharpening.

The kenjig preceeded the more involved computer based programs. I designed it for three groups of Tormek users:
New users. It eliminated the difficulties of learning to use the Anglemaster.
Infrequent users. I was thinking of the home user who sharpened his family kitchen knives once or twice a year.
The farmers market sharpener who had to sharpen many kinds of knives quickly. It was for this group that I created the three jig setup. This would allow the sharpener to switch from a chef's knife to a paring knife without having to change either the machine or jig set up.

The kenjig was designed for simplicity, efficiency, and repeatability. It has two design constraints: A single kenjig is only designed to reproduce one bevel angle. I chose 15°. I also made up a separate kenjig for 20° (which I have never used). I am presently thinking of switching to 12°. This switch to a more acute angle is supported both by Dutchman and later by Wootz. This change will require either modifying my present kenjig or making a new one. Making new jigs requires very little time and essentially no cost.
The second constraint is compensating for eventual wheel wear (decreasing wheel diameter). Again, this is not a problem. My original plan was to make a new kenjig, marked with the diameter for each 10mm of diameter loss. Jan has advised me that going 10mm change would introduce too much error. I present plan to switch kenjigs every 5mm change.

I would interject that Jan has introduced the "janjig" which is double ended and provides Distance grooves for both the grinding wheel and the leather honing wheel, a clever addition.

I like using the TTS-100 for planes because it is also auto correcting for diameter changes. Unlike the Anglemaster, the TTS requires no setting change, even for switching between the T4 and T8. However, I do not feel correcting for diameter change is a major issue. Diamond or CBN wheels do not change in diameter. Even matrix wheels, which do wear, only gradually. The average home shop Tormek user should be able to go a long time before grinding away 5mm in diameter.

The kenjig has never been designed to compete with the more sophisticated computer assisted programs. Setting various bevel angle angles or compensating for multiple grinding wheel diameters is "above its pay grade". It is also not designed for sub 50 BESS.

I still believe it will provide useful service to the new, infrequent, or busy farmers market sharpener. It has served me well.

Ken

[Dutchman]

...
I'm waiting for the musical version. 
...

That would be the right tribute for the most convenient and simplest angle adjustment method 

[cbwx34]

...
I'm waiting for the musical version. 
...

That would be the right tribute for the most convenient and simplest angle adjustment method 

Be careful what you ask for.... 😁

KenJig Calc - The Musical!

[Dutchman]

   GREAT
The song is going too fast for me to understand.
The lyrics would be very welcome.
Perhaps about angles and measuring?

[Ken S]

Much of the confusion surrounding the kenjig comes from mistakenly comparing it with the various computer programs. Examining a kenjig, you will not find a single electronic component anywhere on it. It is not a calculating tool; it is used to transfer predetermined calculations from paper or a computer screen to a knife grinding set up.

Likewise, the computer programs only calculate. They can not transfer these calculations from the screen to the tool.

Part of the confusion comes from videos. I will use Wootz' videos as an example. Wootz does an excellent job of explaining the step by step of sharpening and deburring, including using his computer applet. From a training standpoint, this is excellent teaching. From an efficient operating point of view, going through all of this with every knife seems unnecessary.

I have noticed that the knives he sharpens in his videos generally have a Projection of 140 mm and a bevel angle of 12° per side. This would mean that they all have a common Distance. He has switched to all CBN wheels, which do not change diameter. Whether he sharpens twenty similar knives on a rental contract or resharpens the same knife a year later, none of these settings will change. His applet, or any computer program, determines the settings. The calipers or kenkig transfers these calculations. Both are essential functions.

When the calculating programs and the setting tools like the kenjig coexist peacefully, we all benefit.

Ken

[Hannsi1957]

Hello, Ken,
This is where I start with the laser method. If you have to measure again after every knife as mentioned above, it is time consuming and not necessary. Measuring once at an angle of your choice and then setting the correct toolbar height is enough. All the following similarly sized knives can be loosely inserted into the JIG without measuring. When I place the JIG on the stone, I can align my knife with the laser line, which means my desired angle, and screw it tightly into place. This saves me having to measure the following knives. This should bring a clear time advantage when I am sharpening knives at farmers' markets, for example.

Regards hanns

uupppsssss this works of course only if ur wheels all have the same diameter like my cbn wheels

[cbwx34]

Hello, Ken,
This is where I start with the laser method. If you have to measure again after every knife as mentioned above, it is time consuming and not necessary. Measuring once at an angle of your choice and then setting the correct toolbar height is enough. All the following similarly sized knives can be loosely inserted into the JIG without measuring. When I place the JIG on the stone, I can align my knife with the laser line, which means my desired angle, and screw it tightly into place. This saves me having to measure the following knives. This should bring a clear time advantage when I am sharpening knives at farmers' markets, for example.

Regards hanns

uupppsssss this works of course only if ur wheels all have the same diameter like my cbn wheels

The "KenJig method" just marks a line at the set distance, 139mm for example, (on the jig itself I believe) and each knife is then just mounted using the line.  (So essentially the same method you describe, sans laser).

[Hannsi1957]

you're right, it's the same in principle but with the laser line i have a great aid on the stone when i want to sharpen strongly curved edges to always keep the same angle by turning only on the line. that makes a big difference. i can hit 2 flies with one flap