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[TormekCalc]

Hello everyone,

let me introduce essential tool for all knife-sharpeners – TormekCalc.

TormekCalc is an Excel^* spreadsheet that offers exact calculations and many advanced functions related to knife or tool grinding. It is new generation of the original spreadsheet TormekCalc. Although it may seem more complicated at first glance, for basic calculations you have to enter exactly the same values as in other calculators - Projection distance, Wheel diameter, Grinding angle (and measured machine-dependent constants).


Current version contains these sheets:

• 
  TormekCalc
  
  It allows to calculate the exact distances/angles of different types of support bars from the grinding wheels or machines housing and thus obtain accurate grinder setting data to get desired angle after sharpening knives or tools. Although the name implies use with Tormek grinders only, TormekCalc can be used with any type of grinder.
  
  Main features:
  - Calculation of the Universal support bar (USB) height adjustment for all their types (Vertical, Horizontal, Frontal)
  - Calculation of angle between Universal support bars (USB) and grinding wheel surface which allows setting heigth of USBs with an inclinometer or angle meter
  - Calculation of the USB distance from the wheel surface
  - Grinding angle shift (e.g. for deburring where higher angle than initial is required)
  - Calculations are performed at the same time for all used grinding wheels!
  - Knife / Tool selection - loading stored Knife / Tool grinding data
  - Calculations can be made for different machines, machine selection is under grinding wheels
  - Database selection - loading data from different sheets (Knives or Tools)
  - Jig selection - loading stored jig specification
  - Visible height limits for universal supports US-105 and US-430
  - Knife / Tool info section – shows additional info for selected Knife / Tool
  - Blade material info section – shows additional material info for selected Knife / Tool
  
  
  


• 
  BatchCalc [Non-public module]
  
  Allows calculations for batch sharpening of multiple knives or tools without the need of repeated measuring because it calculates USB height difference between each steps and recalculates it to required Tormek Micro adjust nut turns. However all calculated heights are still available for USB setting or checking. For batch sharpening, of course, you need to have each knife or tool clamped in a separate jig. This version BatchCalc supports batch grinding up to 6 knives/tools in one go but it can be easily increased.
  
  Using and capabilities can be found in this video: https://www.youtube.com/watch?v=9qtyTKqQb1g
  
  Attention: For several different reasons, I have decided that Non-public modules will be freely available only to contributors and donors. Therefore shared public version of TormekCalc contains screenshot and the link to the presentation video only! There is a lot of work, time and know-how behind the development. If in doubt, please compare what the public version of TormekCalc (even the oldest) offers compared to commercially available applications. If you have further questions, you can send me a private message or e-mail message (see FAQ sheet in TormekCalc³).
  
  
  



• 
  Knives and Tools
  
  It allows storing data about sharpened Knives or Tools including used jig, clamping, grinding procedure etc.
  
  - "Picture" column automatically generates jpeg file name + link. To view a picture copy it to subfolder "Knives"  or "Tools" with generated name.
  
  
  


• 
  BevelCalc
  
  Allows reverse calculation of Bevel (grinded) angle through "marker method". USB height measurement can be taken from the surface of the grinding wheel or on any type of USB, it is also possible to enter angle between grinding wheel surface and USB.
  
  Jig selection - loading stored jig specification.
  Machine selection - loading stored machine constants.
  
  
  
• 
  EdgeCalc
  
  Allows calculation of the height and length of the grinded edge which depends on the edge thickness. Calculations are made for flat (ideal) grind and for grind on a wheel, which allows to show deviations caused by roundness of grinding wheels and compare ideal vs real grind. Stored grinding data can be loaded from database.
  
  
  
• 
  CompCalc [Non-public module]
  
  Allows calculation of the grinding angle compensation if wheels with different diameters are used for grinding.
  It is a problem which, as far as I know, was first described by Gilles in this post and calculated using the Polishing angle calc, which is still available there. CompCalc is based on Polishing angle calc, all credit belongs to Gilles.
  
  
  
• 
  Materials
  
  The sheet which allows storing and showing information about various materials used for knife or tool making and material related sharpening procedures or notes.
  
  Basic material information and material related sharpening procedures/notes are also displayed in TormekCalc sheet if the knife/tool is selected through drop down list and blade material is stored in the Knives/Tools sheet. If an exact match isn't found in the Materials table, program tries to find first match in the material Aliases, if the search is successful, offers the matching material, if not, it tries to find the match in the Proprietary equivalents.
  
  
  
• 
  Hardness
  
  A new sheet containing information/convert tables for different hardness scales.
  
  
  
• 
  Jigs
  
  Allows storing properties of various jigs (even own or from other producers) and consequently using them for the calculations and for quick jigs selection through drop-down list. It includes Projection length correction X+ which is intended for cases where it's imposible accurately measure the projection length (measuring point inside the jig). Correction X+ is then automatically added to the length that was measured at another point on the jig (e.g. SE-77).
  
  
  
• 
  Wheels [New]
  
  New sheet which contains a list of available wheels for various Tormek grinders (T-8, T-4, etc.) and possibly for other ones. On the TormekCalc sheet, the wheels in use are selected from this list.
  
  
  
• 
  Settings
  
  Allows setting default values for all sheets in one place.
  
  Allows specifying dimensional constants for different grinding machines. Defined machine setting can be used for calculation in TormekCalc and BevelCalc sheets and it helps in all situations when grinding on multiple machines. The machine selection allows automatic calculations without the need to manually enter dimensional corrections.
  Specification is universal and is not limited to Tormek machines only, it works virtually with any grinder.
  
  
  
• 
  FAQ
  
  Just a few answers to Frequently Asked Questions. (Single bevel knives, FVB, etc.)
  
  
  
• 
  Languages
  
  Multilanguage support. Currently available languages: English, Czech, French (thanks Gilles!) and German (thanks Stephan!)
  
  
  
• 
  VB [New]
  
  New sheet which contains VBA tools - Backup and Data Import from previous TormekCalc versions.
  
  

Ideas for improvement are welcome as well as feedback. Please feel free to contact me if you need any further information.


Enjoy!


jvh

*) Tested with versions Excel 2010, Excel 2013, Excel 2016, Excel 2019, Excel 2021. Not compatible with Excel 365 since version 3.10.
    Not compatible with Google Sheets and others which don't support Structured references.


Attention!

Due file size and forum restrictions (maximum individual size is 256 KB) is TormekCalc version 2.1+ available only via external web storage.

Download HERE (WebShare.cz, click Download File and then Download slowly, PM me for the password).

Current version 3.10
(TormekCalc_Public_v310.zip, packed size 2 859 167 bytes, TormekCalc_Public_v310.xlsm, unpacked size 3 000 289 bytes + sample pictures in the Knives and Tools folders.)

I have now tried to make a spreadsheet again. But I can't seem to get it to work.
I want it to calculate the height of the USB, vertically from the top of my Tormek T8. The same way as Knifegrinders App is working. The reason why i just don't buy the app is because i would like to be able to get the measurements for both the vertical USB stand and the horisontal at the same time, and over time also the FVB. So i don't need to use the program more than once, if I want to use both (all tree) USB stands.

Hi BennyJ,

did you try TormekCalc?



TormekCalc 2 comming soon...

[HAIM]

Hi,

I vote for a belt grinder if there is a lot of grinding. I haven't got it for a long time, still learning, but it's a really time saver. 

jvh

Who makes this grinder?

It's HAIM H01 with mounted contact wheel 250x50 mm and knife sharpening support. Very versatile machine with a lot of accessories available.

jvh

My problem is how to to or use when there is alot of grinding to remove a nick or when the blade has lost a small shard.

Do you use a beltgrinder or how do you do in these cases?

//Thomas

Hi,

I vote for a belt grinder if there is a lot of grinding. I haven't got it for a long time, still learning, but it's a really time saver. 

jvh

Hi Peter,

I take the FVB as an extension to horizontal universal support bar (USB). It offers possibility of grinding wide knives, choppers etc. if the jig projection lenght exceeds ca 150 mm.

In addition, grinding with FVB gives me better control and is more ergonomic for me due its position while grinding away from the edge or honing.

jvh

[In both cases, the distance from the usb to the center of the stone must be the same.]

Have you tested whether "grinding with the wheel rotation is different to grinding into the wheel"?
In both cases, the distance from the usb to the center of the stone must be the same.

There is no difference in the grinded angle if you use correct calculations and well measured constants for your Tormek machine.

Photos...

Hello everyone,

there is my version of Frontal vertical base, see enclosed drawings for details.

My first version had one threaded rod but I found it unnecessary because usually is FVB located on the stops or on defined steps. Therefore I made small notches on the surface with pipe cutter and I can replicate defined lenght easily.

Some notices:
- Adjusting rings are located 24,5 mm from the FVB body and it is minimum distance to avoid contact FVB with the Tormek's body (untouched painting). This distance can vary little bit on other machines.
- You can use round bar with drilled hole and internal thread instead of seamless tube.
- A little problem is with counter-nut's M5 tightening - there is not much place for the spanner. Something like Bahco 1931M-5 comes handy.
- Washers M8, ISO 7093 give enough support between tube and FVB body, the design is rigid. No problem after 6 months using.
- The dimension 30,85 (and 30,15 mm) can vary little bit too but it is exact distance to have my piece of Tormek Horicontal Base XB-100 centered with FVB body.

Enjoy!

jvh

Hello everyone.
The following comment is not to solve the "problem" about the thread of discussion, but I think all points of view are interesting.

I have no advanced mathematical knowledge and it is impossible for me to offer a qualified point of view, but I have the other part of the equation: the practice.

I received the actualizated app of Wootz and I have used it in (about) 40 knives including the day of today.
This knives been between 0,4mm to 2,5mm thicknes behind the edge.
Absolutly all the knives finished in target angle. The comprobation of the angle was with Catra Laser Protractor.
I know the Catra have a tolerance, but the ressults have been clarifiers in my opinion.

Nothing more. I would like to have enough level in order to clarify this problem, but only can offer this.

Regards

Hello,

thank you for your report. Can you give us more information to get a better overview?

Did you check angles also when you were using previous version of app and did you notice some difference between old and new results?

Which angle did you grind typically and what was overal range of angles which you grinded on last 40 knives?

Regards
jvh

Just one thing though. I don't think it is correct to describe the angle variations that occur along the bevel as 'errors caused by roundness'. To me this terminology suggests the angle calculations are wrong or approximate which is not the case as the maths is precise.

That's true, "errors" has been changed to "deviations". Thank you.

[X]

... and measure the projection distance, I am measuring the total projection distance (Ke).  I'm never measuring to "Kb".  So, the calculator/formula automatically is set for the angle I want to end up at.  While it is obvious that at the start of the grind, the angle of the knife/wood in relation to the stone is different, at the end, I'm getting the angle the calculator provided.  That's the way I see it anyway.  (I actually did it to see if I was missing something).

I explained this partially in my previous post (Reply #33 on: November 04, 2019, 07:24:36 pm).

We can say that that total projection distance X is always right. The dimension starts at the edge tip and this is also the first point of our axis.

If you have symmetrical double bevel knife and you center it well in the jig SVM-45 then the second point of axis lays in the axis of the jig and goes through point J.

Now it depends on used math because you can suppress this "thickness error" from the beginning with the correct calculation.

TormekCalc calculations are made in the axis of the knife (point at edge tip) and the jig (point J), so results are valid for all symmetrical double bevel knives with defined angle at the edge tip. Error given by material thickness is suppressed there completely.

For single bevel knives or non-symmetric bevel knives is a correction necessary to get the "right" axis.

1. You can put some distance pad to the jig clamp to get "virtual symmetrical" edge - then the edge tip will shift to the axis of the jig.
2. In TormekCalc you can change diameter of USB or jig diameter value and "virtually" move the jig axis to the right place by change the JC dimension. Then you get exact results for single bevel or non-symmetric knives. Error given by material thickness is suppressed by the jig axis shift.
3. You can change USB height too but there isn't exact calculation for this at the moment.

jvh

Screenshots...

[EdgeCalc]

Hello everyone,

for precise outputs and for an idea what's happening on the knife-edge during grinding I made EdgeCalc - Excel spreadsheet which lets you calculate deviations caused by roundness of grinding wheels. I plan to add this functionality to TormekCalc in the future but this solution is much faster.

EdgeCalc contains drawings with dimensions for better visualization and it will help you if you want to validate used math in formulas. I tried to describe all, but there can be problems with used terminology. If you have better idea please write it here and I will release updated version. Any ideas for improvement are welcome as well as questions.

Table is locked by default (without password), only three green input cells are editable. Feel free to unlock it if you know what you are doing.

Enjoy!


jvh

Note: File is compressed to zip format (forum restriction), you have to unzip it before using.

[a good method to set the USB gives the "KenJig"]

However, a good method to set the USB gives the "KenJig".
There is no better way. 

Excellent advice for verification! 

I would like to add that this "KenJig" dimension ("T" in my drawing) stays the same for all types of universal supports (on the same wheel for the same grinding angle and jig projection length).

jvh

[quantify the overall error]

We then made another round of the above 100 sharpening sessions to confirm the new algorithm on 2 Tormek-8 and 2 Tormek-7 machines, as detailed in the Software Testing on our website http://knifegrinders.com.au/software_testing.htm

Our computer algorithm is the most accurate and the best tested.

Sorry, with all respect to you I have to say that it's just your statement without any evidence. Your test results looks like from ideal world, at least you should quantify the overall error (systematic + random) that occurs during your measuring and grinding. Otherwise your results looks suspicious.

I cannot verify your testing procedure but I saw in your videos (in production run!) some problematic parts with length and angle measurement which I pointed in my previous post.

In my opinion, these errors and used equipment do not allow you to work with the accuracy you declare.

That's all, have a nice day.

jvh