A Faster, More Repeatable Way to Set Up USB Height?

[Fluehue]

You're correct, there will obviously be variances between individual Tormeks. Only Tormek knows what tolerances their machines are built to (I vaguely recall a Tormek factory video showing it using Mitutoyo measuring equipment). Tormek also claims their T8's zinc body casting is "more accurate" than their T7, although I have a feeling that is more about the old XB-100 possibly being mounted skewed.

So we are forced to assume all machine measurements are the same, and that the machine top is perfectly parallel with the drive shaft. But errors are often cumulative (if you're really lucky, they could cancel each other out). So it's best to be as accurate as possible.

Some of KnifeGrinder's protocols involves decreasing the honing angle by .1 degree. That's why I analyzed whether a 1/64" step variation in drill bit sizes is sufficiently "fine" enough for that. I showed that it isn't. (For the record, I don't bother with the minus .1 degree step either).

It's a compromise between time, sharpness/edge retention, and equipment cost. I'm just trying to show a compromise between the three that fitted MY needs (under 5 minutes per knife / long edge retention (not ultimate sharpness)/ $50 investment).

Thank you for your answer
I have been wondering, what country are you based in. I would like to come in contact with other Scandinavian knife sharpeners that do this for a living. I have started my own company and thought it would be nice to share ideas and other stuff with each other. I have many hunder hours with different tests in my workshop and I'm sure you others do aswell. Together we could become even better and talk more regulary. I alreaddy have contact with a very nice and humble fellow sharpener in Denmark.

[BeSharp]

I'm in Vancouver, B.C., Canada 🇨🇦

[jvh]

Everyone's needs are different. I picked a path that I felt best suits my business needs. What I chose may well be totally wrong for others. There is no best path for everyone.

Thanks for the reply, it is true and I have no problem with that. I asked because the reasons for the development of TormekCalc, among other things, were limitations in applets - the need to repeat calculations, the inability to save settings, a separate applet for each machine etc. And all these missing features mean more time needed...

I really love to see that it's not just me that are completely hung up on 1/100mm. But my question is this. If you use the software from KnifeGrinders. The machine measurements are preloaded into the software. We know that not all Tormeks are manufactured within 1/10mm of each other. So even if you get every measurement 100% it is probably wrong since your machine is not the same as Knife Grinders machines.
So my question is this. How important is 0.1mm?

That's a good question and I usually try to be as precise as possible, because accuracy is my hobby. 
I have to agree with cbwx34 that consistency is a basic prerequisite for sharpness but I have to add that accuracy of setting (if you sharpen on different stones), is one the key how to get burrless and exceptional sharp edge even before honing.

How to reach the USB setting accuracy ±0.1 mm or better between different stones?
Using a caliper is one option but it requires precise measurement. BeSharp's spacer method is other option, easy and precise. KenJig is next easy and precise method.
But what about to calculate number of required Micro Adjust turns between two stones? Micro Adjust is graduated for each 0.25 mm, it is not so difficult to set it ot the half of graduation which is 0.125 mm. For me it's easy and precise enough...
Yes, there still remain deviations in protrusion measurement, USB height measurement, constants measurement which affect final angle but not final sharpness. Deviations which has impact to final results you can minimimize - if you want.


jvh

[cbwx34]

...

That's a good question and I usually try to be as precise as possible, because accuracy is my hobby. 
I have to agree with cbwx34 that consistency is a basic prerequisite for sharpness but I have to add that accuracy of setting (if you sharpen on different stones), is one the key how to get burrless and exceptional sharp edge even before honing.

How to reach the USB setting accuracy ±0.1 mm or better between different stones?
Using a caliper is one option but it requires precise measurement. BeSharp's spacer method is other option, easy and precise. KenJig is next easy and precise method.
But what about to calculate number of required Micro Adjust turns between two stones? Micro Adjust is graduated for each 0.25 mm, it is not so difficult to set it ot the half of graduation which is 0.125 mm. For me it's easy and precise enough...
Yes, there still remain deviations in protrusion measurement, USB height measurement, constants measurement which affect final angle but not final sharpness. Deviations which has impact to final results you can minimimize - if you want.

jvh

I agree with this, but I was specifically referring to not worrying about the claimed .1mm or .1° accuracy.  It's simply not there... in particular switching between Knifegrinder's apps. ( I'm pretty sure the argument could also be made that the original study wasn't actually setting angles with that level of accuracy either, so the "need" to make .x changes isn't necessary for that reason also).  The apps don't do it... so there's no need to worry about the .x accuracy.  But you get consistency... so nothing wrong with following it.  I think the process makes the knife sharp... not the accuracy... i.e. just creating a burr and honing it off (often in multiple stages).

Even using just one app or calculator, I would question the ability to set angles to that degree (pun intended).  For example, the recent discussion of angle changes just switching between stone sizes... the basic calculators don't account for that... it takes additional calculations.  NOT significant in most cases... but .x accurate???

The reality, you/anyone could probably come up with a variety of processes of sharpening and honing that would give the same results, without the "need" of such small adjustments.

[jvh]

Even using just one app or calculator, I would question the ability to set angles to that degree (pun intended).  For example, the recent discussion of angle changes just switching between stone sizes... the basic calculators don't account for that... it takes additional calculations.  NOT significant in most cases... but .x accurate???

The reality, you/anyone could probably come up with a variety of processes of sharpening and honing that would give the same results, without the "need" of such small adjustments.

Hello,

reach the accuracy about 0.1 mm between the stones isn't so difficult. USB has thread pitch 1,5 mm and Micro adjust nut is graduated by 0,25 mm. If you take a half division you have 0,125 mm. It would not be difficult to achieve a quarter division (and I tried it), but it is not too practical. If you know this, just measure the height of the USB at the first stone and then adjust it just by turning the Micro adjust nut. Of course, you have to calculate difference between stones and... you are right, basic calculators don't account for that, so you have to calculate difference between stones manually. I am to lazy to do this way... 

jvh

Note: The examples are not from actual grinding procedures, they are only used to give you an idea...

[cbwx34]

Hello,

reach the accuracy about 0.1 mm between the stones isn't so difficult. USB has thread pitch 1,5 mm and Micro adjust nut is graduated by 0,25 mm. If you take a half division you have 0,125 mm. It would not be difficult to achieve a quarter division (and I tried it), but it is not too practical. If you know this, just measure the height of the USB at the first stone and then adjust it just by turning the Micro adjust nut. Of course, you have to calculate difference between stones and... you are right, basic calculators don't account for that, so you have to calculate difference between stones manually. I am to lazy to do this way... 

jvh

Note: The examples are not from actual grinding procedures, they are only used to give you an idea...

Theoretically... maybe... practically, I say... no way.  Heck, I doubt a stone is accurate to that level. 

Open a caliper .1mm... you can barely see light thru it.

We don't even have the (practical) ability to measure such a change... let alone say it makes a difference in "sharp".

[Dutchman]

... snip
We don't even have the (practical) ability to measure such a change... let alone say it makes a difference in "sharp".

Agree!
Moreover, you have the best accuracy if you allow as few variables as possible to determine the tolerance in the accuracy. Hence your app "Calcapp calculator" at https://connect.calcapp.net/?app=qq0pg0#/ is the best app for this topic imho. 

[RickKrung]

... snip
We don't even have the (practical) ability to measure such a change... let alone say it makes a difference in "sharp".

Agree!
Moreover, you have the best accuracy if you allow as few variables as possible to determine the tolerance in the accuracy. Hence your app "Calcapp calculator" at https://connect.calcapp.net/?app=qq0pg0#/ is the best app for this topic imho. 

I'm curious about this statement, Dutchman.  I would think that the direct measurement of the distance to the stone from the USB would be the method with the fewest variables, which more than "Calcapp" offer, do they not?  I haven't followed or looked to check, but I thought the spreadsheet one does also.  I use GoCalc, but it is just another platform of CB's Calcapp, if I'm not mistaken.

Rick

[cbwx34]

... snip
We don't even have the (practical) ability to measure such a change... let alone say it makes a difference in "sharp".

Agree!
Moreover, you have the best accuracy if you allow as few variables as possible to determine the tolerance in the accuracy. Hence your app "Calcapp calculator" at https://connect.calcapp.net/?app=qq0pg0#/ is the best app for this topic imho. 

I'm curious about this statement, Dutchman.  I would think that the direct measurement of the distance to the stone from the USB would be the method with the fewest variables, which more than "Calcapp" offer, do they not?  I haven't followed or looked to check, but I thought the spreadsheet one does also.  I use GoCalc, but it is just another platform of CB's Calcapp, if I'm not mistaken.

Rick

Thanks Dutchman...

Rick, you are correct, more than Calcapp give the "USB to Wheel" measurement.  For example, in jvh's TormekCalc spreadsheet, it's given as "T USB", as seen in the picture (I also show the related "help" notes)...



I think you may be the only one using the GoCalc app.   

[RickKrung]

...snip...
I think you may be the only one using the GoCalc app.   

Fine by me.  I just hope it stays available.  Simple, easy to use and lives on my iPhone and is with me continuously. 

Rick

[jvh]

Hello,

O.K., I try it once more because this topic name is "A Faster, More Repeatable Way to Set Up USB Height" and I think it doesn't mean repeat calculations and measurement of USB heigth over and over again between stones and knives when it's not really needed.

Agree!
Moreover, you have the best accuracy if you allow as few variables as possible to determine the tolerance in the accuracy. Hence your app "Calcapp calculator" at https://connect.calcapp.net/?app=qq0pg0#/ is the best app for this topic imho. 

IMHO it depends on accuracy of the constants measurement. If you do it precisely and/or check results via distance from USB to the stone surface and make the corrections the deviation between measurement to the stone surface or Tormek's body is neglible. Personally, I consider both methods to be completely comparable.

I would like to add again that all calculators are nearly the same in "basic" mode because you have to enter the same values - Projection distance, Grinded angle and Stone diameter (and constants if you want to measure from Tormek's body.)



Now example from batch grinding of three knives on the same machine. Only two measurement of USB height are needed - one time for vertical USB and one time for horizontal USB. All other settings was done by turning of micro adjust nut because height difference between each step is calculated, thread pitch is 1,5 mm and Micro Adjust nut is graduated for each 0,25 mm. Calculation is precise, results are rounded to 1/12 (double graduation of Micro Adjust nut), showed value is halved (eg 0,5/6 turns), which correspond to 0,125 mm. More description you can find in the picture.

All values are calculated in one go and, of course, you can check heights at any moment...


jvh