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Interesting idea and challenge. I don't think it's impossible, but it requires some thought and some calculations. I've been thinking a little along the same lines for a jig for convex blades but it's on hold right now.

I think the question already been answered. 

I'm pretty sure you can.  I learned it from jvh in this thread that the formula is a bit "generic" (for lack of a better word?). It will calculate the USB height, as long as you can figure out the Jig Diameter, and Projection Distance adjustments.

Thanks cbw..
You are right, as always. Just haven't thought of the possibility myself. 

try to reformulate my question: does your software take into account that some jigs are so thick, that the projection line is shifted several millimeters up resp. out of the center? (In case of the SE-77 this has a fulcrum point at the USB, but the projection line is several cm away).

Hello
The program is also designed to be used only for knife jigs. In settings you can adjust the jig diameter for different jig thicknesses, for example my KJ-45 is 11.8mm in diameter. There is no possibility to move the fulcrum to fit other types of jigs.
This might be a 'gewgaws'

The final version of this tool now looks like this. I've made a number of it that I've sent off to knife sharpeners who want to help test and evaluate it. Maybe it will be available for purchase in the future, if it gets good reviews. The scale You cannot view this attachment. Its not gold, only brass!

Hi
Sorry; I'm probably not quite sure I understand your question. But the idea has not been to use it for anything other than knife jigs.

He was truly an enthusiast and inspirer that is missing in our world.

Thanks HaioPaio
To be honest, the only thing the tool really does is help you adjust the USB height to a defined value taking into account wheel size and jig projection distance. You then sharpen your knife with a grinder and selected jig and use the setting you have made. The tool is not used for the grinding part. So you have several points with your comments. The accuracy of the tool can of course be compared to other methods of setting the USB height, but it does not guarantee how you grind and whether you reach the angle you think you have set. There are many parameters that come into play as we all know. Kind of grinding wheel, material in the knife blade, how to handle the actual grinding and honing with pressure, speed etc. I think the tool can repeat the setting as well as many other methods at least theoretically but as you said it doesn't really matter that much it's more of value that it is a simple and fast operation that you believe works for you. If you then grind 16.5 or 17.5 degrees is not so important only you are satisfied and proud of what you have done. The main goal of this project was to simplify the setup process and not have to measure so much and not have to use a calculator, and I have come pretty close to that, I think. Accuracy was not that important. 0.5 was a measurement value on the road that I actually chose because the scale is divided into half degrees.
I think the interesting question of being able to repeat a grind at the same angle multiple times is a different issue regardless of what tools you use to set up your machine. Maybe requires its own thread?

And with that said, I have to admit one thing. To sharpen precise angles on knives, I use another grinding tool that is more precise than the Tormek can handle. Sorry Tormek

Hi HaioPaio
That's a really good question. I think many people, (grinder) out there, like me, have a hard time verifying the amazing results we achieve with our Tormeks. Especially when we have to measure and prove the grinding angles we say we grind at.
When it comes to verifying the ability of the tool WAT, I have worked with control measuring with a number of other methods. USB heights and projection length from calculation programs that I then compared to what WAT shows etc.
But back to your question.  How to measure a knife's bevel angle!
I have tried several different ways, one is to use a laser protractor or laser Goniometer for knives. But my experience is that it is difficult to measure closer than approx. 1 degree or more with a laser pro. See picture
Another way I have tried is with a microscope where you can measure angles, lengths, etc. but it is both a bit complicated and requires some knowledge and special equipment. The way I use right now is to use another sharpening equipment that I have made to sharpen really fine knives with. It can also be used to check existing angles with.
I would like to show some pictures of how it works, but unfortunately I am traveling this week so if I can get back to you in approx. a week I can post more information about this.
 In the meantime, there may be others in this Forum who want to share how they do it.

Thanks CBWX.
It is correct, as you noted about to be extra precise, you can slide the ruler in or out to hit the "zero point". There is a difference of 0.58mm on the ruler's protrusion to hit the zero point between a wheel of 200mm and one of 250mm. But it is of course difficult to adjust a ruler 0.58mm without the help of a measuring tool. As I mentioned earlier, it is not meant to be a precision tool, so I have chosen to set the ruler to a fixed measurement in the middle 0.58/2=0.29mm. That is sufficient to reduce the margin of error to an acceptable value. There is a built-in option, settings ability between 23.7 and 24.3, to adjust this in the tool. Measured from the tip of the ruler to a specific point. I have set, and use, 24mm for all wheel sizes. The same thing with the wheel dimension on the scale, there is a very small adjustment between 200 - 250 wheels (only 1 degree) so to adjust for example a 240mm wheel, you hardly move the scale at all. After a while you learn when you need to move the scale to be within the tolerance you want. As few settings as possible is a goal.

Hi Dutchman You can slide the scale up or down to set the wheel size between 200 to 250mm. It is approx. 1 degree between 200 and 250

I understand and agree with your views Ken. However, this tool is not intended to be a precision tool, it is intended to simplify and speed up the setting and to avoid measuring and keeping track of various measurements and calculations.

A little update on what became of this project. Now the tool is ready and printed on my 3d printer. We are happy with the result and my friend uses it in his workshop.
The scale is now adjustable for different wheel diameters, 200 - 250 and also the length of the ruler's protrusion if you want to be even more precise. You can easily set the length of the jig with a knife directly on the tool. All the parts fit together and you can lock the setting with locking screws on the back, if you want, after making a setting. We find it easy and fast to work with and the accuracy meets the requirements we had, within approx. 0.5 degrees. End of this project.

Thanks a lot CBW I will definitely read through your suggested threads.
Yes, maybe Kenjig is a good solution for him too. Yes, I admit, I cheated a little. Technically, I measure projection distance but without noting any values. I just physically copy the length to the T-cube. Think it is technically impossible to try to solve this without having at least one fixed value to start from.
My goal is to avoid both calculators and measuring tools such as calipers etc.

And he knows the marker pen method. I told him the black one is 18 degrees and the blue one is 16... but he didn't believe me!

He has tried it a bit and is not satisfied with the handling. There are too many loose parts to handle at the same time as he has to read the scale and raise the usb support.
I am now looking at version 1.1, where the parts should fit together and make it easier to handle with one hand.

That's why I'm waiting with tables of measurements that still have to be measured somehow.
Hope that it is possible to find an acceptable level of the deviation in some way. The tests I do show that I hit very close to 0.5 degrees when I countermeasure with other methods.

Don't know what deviation Tormek's Anglemaster has.

What deviation do you think is acceptable on a tool like this to use it?

Hi Dutchman
I have the same result as you have. So that's good.
But I have calculated wheels from dia 200 to 250 and that gave me 2mm variation, then I moved up the center point of the scale 1mm to halve that error. Maybe it's not quite right to do that? but as you point out, there are more parameters to consider. It is also a bit difficult to hit the right spot with the ruler. Do you have any other solution to reduce the margins of error on?

I have collected some pictures and user information about my latest project, WAT-prototype, in a pdf file. Attached below. Happy to receive thoughts and ideas about how a finished jig could look like! Or thoughts about function and precision. Have tested it on different wheels and with varying degree numbers and jig lengths and so far I am positively surprised by the result. The T-cube has already been presented before.

With this two tools you can set the grinding angle for knives on a grinding machine with rotating grinding wheels or honing wheels from Dia 200mm and up without using a calculator. There is no need to measure wheel size, usb height or projection length. It is possible to set degrees with an accuracy of 0.5 degrees.

There is already a small thought with me to produce a template for a 3d printer if it works well and if someone wants it. However, it is quite easy to make it yourself if you want.