Simple adjustment of the grinding angle

[Dutchman]

I have developed a method for simple adjustment of the grinding angle with the knife jigs SVM-45 and SVM-140.
Coarse adjustment is done by setting the distance of the universal support to the stone in steps of 5mm.
The fine adjustment is done with the adjustable stop of the knife jig.
The required adjustments for a certain grinding angle are listed in tables.
Tables are made for stone diameters from 240-180mm, in steps of 10mm

The method is documented in PDF-files which can be downloaded from Dropbox:
https://www.dropbox.com/sh/zfzeuyyhors8oid/Yyq5S71LxR
• "Grinding angle adjustment Booklet.pdf" should be printed two-sided on A4 paper.
  You can then staple and fold it as an A5-booklet. It should also fit on 'US legal' size.
• "Grinding angle adjustment A5 serial.pdf" , is the A5 serial version, for storing in iBooks on iPad.
  This document is also attached at the end of this message

20180702
At the request of "cbwx34" I developed mathematics for use with its robust "jig-fix" as published on https://forum.tormek.com/index.php?topic=3570.msg22912#msg22912
The new formulas can also be used to choose a different reference point for the distances than the center of the jig's stem, which is unclear and inconvenient.
As a result, the setting of the sharpening angle can be determined more accurately.
Some measurements were also made from which possible sources of error appeared.
The new document is titled "More math for the Tormek grinder"
You will find the documents in the public folder "Tormek-T7 grinder":
https://bit.ly/2lHaR3m on DropBox
https://bit.ly/2KpROFg on OneDrive
The new documents are:
    • "More math for the Tormek grinder A5 serial.pdf", serial version for tablet
    • "More math for the Tormek grinder booklet.pdf", A5 booklet to print on A4
  This document is also attached at the end of this message
    • "USB adjustment table.ods", spreadsheet to generate the new table

20221021
New tables, useful for Knife Jig KJ-45
With the new Self-centering Knife Jig KJ-45, the projection distance can no longer be adjusted, due to the lack of the adjustable stop. My tables, however, were based on coarse adjustment with the USB and fine adjustment with the adjustable stop. These are therefore no longer usable with the KJ-45.

Forum member Perra has created a spreadsheet to generate other tables useful for the KJ-45.
See https://forum.tormek.com/index.php/topic,4885.msg37010.html#msg37010
You measure the projection-distance (between stop and knife edge) and the table gives you then the correct USB distance to the stone for a certain grinding angle.
The stone diameter is one of the parameters to be set

20221031
cbwx34 added the link of available calculators: Knife Sharpening Calculators

20230505
Benjamin Hung "benhung" has made a graphical representation of the relationship between the various parameters. This will give you a good understanding of how it works. The values of the set parameters are displayed and can therefore also be used as a calculator for the grinding angle.
You will find the message on:
https://forum.tormek.com/index.php/topic,5254.msg38240.html#msg38240
and the graphics on
https://www.geogebra.org/m/wwuqbvhh
Finally, Benjamin has posted an extensive and amusing explanation in this topic at https://forum.tormek.com/index.php/topic,1849.msg38339.html#msg38339

20221025
Attached documents

[Rob]

Well that was quite comprehensive.  Well done and thank-you for the introduction of trigonometry to blade sharpening :-)

Out of interest, how long have you been using your method and what results can you report (anecdotally I appreciate)

[Dutchman]

Thanks. 
I started with this method in august 2013. I calculated the settings with a hand-calculator.
It turned out that it was indeed easier than the method described in the handbook, once you know the settings.
Then I made a spreadsheet to generate a table and made some notes for a report.
Last december I made all the tables and the document.
Recently I decided to share it with the Tormek community.

Regarding 'results', there is nothing to show. It works fine.
I can not report on 'efficiency' because I use the grinder only for my own tools and knifes as hobby, not for my profession.

By the way, I added a note to Table 4 (Stone diameter 220mm) that it can also be used for the honing wheel. 
The documents have been updated.

[Herman Trivilino]

Interesting discussion of edge angles for kitchen knives, there.  I have found that with the Tormek there is no need for secondary bevels because knives never get "harder to sharpen" on a Tormek.  As to the perfect edge angle, well, that's elusive.  I've found that it depends on the type of cutting you do with the knife.  For me, I like my paring knives at 30^o (15^o on each side).  Butcher knives 40^o.

If I have a nice pocket knife I usually try to match the manufacturer's original edge angle.

By the way, I know we'll never resolve the terminology issue, but what you're calling the grinding angle is what Tormek calls the bevel angle.  To me, the edge angle is the angle at which the edges meet.  So the edge angle is twice the bevel angle on a typical knife that's ground symmetrically on both sides.

[Ken S]

Excellent work, Dutchman. I downloaded your booklet into the ibook pdf collection on my ipad.  (Quite easy to do.  just tap on the upper right corner of the open document.  "save to ibooks"will appear.  tap that and it is done.  I mention this because it took some trial and error to discover it.)

You have made a major effort and have done the hard work.  I will refer to your booklet several times. The next time I sharpen my kitchen knives I will spend a little extra time and study to incorporate your ideas.  That time will be well rewarded in both efficiency and precision for all future sessions.

Anyone unwilling to learn this new method will remain in the primitive trial and error era.

Your ideas can be applied to sharpening other edges (chisels, plane blades, etc.)

Thank you and keep up the fine work.

Ken

[Dutchman]

Thanks Ken.
I was wondering if my method would attract proper attention.
Your answer completely reassured me.
Ton.

[Ken S]

Ton,

When this forum is really working at its very best, ideas begin, are shared, and grow.  One of the best examples of this is the small knife jigs produced by members (Ionut and Herman).  The original idea for these jigs was my post (#854, Jan 28, 2011).  I described some jig ideas.  Ionut made a working jig from these ideas.  Herman also made another fine jig.  Unfortunately, Ionut has been inactive for quite a while.  Herman has done great things with his small blade jig....everything from small blades to machetes.

You might be interested in some chisel thoughts (with fixed standard distance and blade projection) I posted a while back (post numbers 821 and 822 of February 2011).  They have a similar flavor (on a much simpler level) with your well developed knife sharpening thoughts.

I hope you will continue to post.  You have very good ideas, and the willingness to see them come to fruition.

Ken

[Dutchman]

Hello Ken,
You refer to certain postnumbers which I would like to read.
How do I find or search these posts?
I don't see where and how the posts are numbered.

[Jambe]

 Re: Simple adjustment of the grinding angle
« Reply #7 on: Today at 03:01:53 am »
               ^

[Ken S]

Ton,
I found the post numbers by clicking onto my name and selecting "show posts". 

I did this only after having no luck with the site search function. (I have not had much luck with the site search function.)

I am no computer genius, however, the setup of the numbering system seems flawed.  Individual post number one is the most recent post.  That means by now my post #854 is probably #856.  For someone with half a dozen posts, that's not a problem.  With people like Jeff Farris, Herman, Rob, or me, with plus or minus a thousand posts each, that's very clumsy. 

Just reversing the numbering system to first (oldest) post being #1 would improve the situation greatly.

I propose a better solution.  Instead of quoting post numbers, the poster would make life easier for all of us by copy pasting the post or part of the post.  The poster would need to note who is being quoted and place quotation marks.  Personally, I have found that easier than using the site's quote feature.  Or, for those who prefer to use the quote feature, just use it.  The point is let's provide the reader with the answer rather than a roadmap of how to hopefully reach the answer.

I normally wouldn't post this much, but here is the copy paste of those three posts.  By the way, after bisecting my torlock jig, I realized I did it wrong,  Jeff Farris made an excellent suggestion.  If you are interested, I will share that experience in another post.

Ken

Here is the copy paste:


854
General Tormek Questions / Re: Free hand sharpening
« on: January 28, 2011, 11:31:38 am »
The ideal solution would be to visit your local authorized Tormek dealer and purchase an SVM-15 Small Knife Sharpening Jig.  Unfortunately, that won't work.  Tormek doesn't make such a jig.  So, here's my 'Plan B":

Start with an SVD-110 Tool Rest.  You may already have one. If not, they are inexpensive and versatile.

For clarity, I will refer to the SVD-110 as the "Tormek platform".  The part you make will be the "blade platform".

I suggest you start by making a mock up.  Mine was just three layers of cardboard cut to 2" x 8" and a couple clothespins. Quarter inch plywood or Masonite would be ideal.  Beveling the underside of the mockup piece will let you get closer to the wheel.  I just staggered the cardboard layers.

 Set up your Tormek with the universal support bar in the horizontal position (wheel revolving away from the blade).  Install the Tool Rest jig.  Place the mockup (henceforth referred to as the blade platform) on the tormek platform.  For starters, place it lining up with the left edge of the Tormek platform and protruding about two inches beyond (toward the stone).  Secure with the clothespins.  Set with the angle jig to 20 degrees.  Follow the general Tormek safety practice of allowing 2mm (3/32") clearance between the jig and the grinding wheel.

I used my pocket Swiss Army knife with the prototype.  The small blade rests on the blade platform.  DO NOT TURN ON THE POWER.  With the blade resting on the blade platform, swing it to follow the arc of the edge. Notice the two inch dimension matches the width of the grinding stone.  This lets you position both sides of the blade without moving the jig. 

Using the mockup prototype will let you see how much platform protrusion you want. YOu want it short enough to be rigid and long enough to swing the blade arc. Making the mockup requires very little time and no cost.  It will speed the end result.

Once you have decided to proceed, you will probably want to add some shoulders on the bottom side of the blade platform to register against (rest against) the Tormek platform.  This will keep the platform from shifting.  I would consider an ideal final shape to be wide enough to allow shoulders on both sides of the Tormek platform, with the protrusion notched to two inches (to match the width of the wheel).  I would place a shoulder under the front edge for the shortest protrusion you wish.  The back shoulder could either be placed for this position or moved back to allow a longer protrusion when needed.

Vise grip makes a nice small plier type of clamp which allows for the back of the Tormek platform not being parallel.  This clamp can be pre adjusted and popped on and off as needed.  A regular C clamp ("G cramp" for those of you who still speak English) would do fine.

I use Baltic Birch Ply  for lots of stuff.  Unless you use metal, the water from the wheel will create a harsh environment for your jig.  Paint it, or otherwise seal it.  It probably won't last "forever", but should give good service.

This simple jig will not give the ease of use the regular Tormek knife jigs do.  It should give you more control over the angle of the bevel.  You must lay the blade flat on the platform; the jig does not actually hold the knife.

I would suggest starting very gingerly with the stone fully graded fine, or, as mentioned by Gary, on the leather honing wheel if the knife is not very dull.  The coarse stone can be used to rapidly create "nano knives" which may not please your customers.

I hope this helps.

Ken
      Reply
      Quote
      Notify



821
General Tormek Questions / Re: switching between wheels
« on: February 12, 2011, 04:36:00 pm »
Steve,

I don't do movies.  However, the movies on this website can help you.  Watch the movie associated with the TTS-100.  It will show you how to set the distance from the stone to the universal support bar using the TTS-100.  (I suggest using the thirty degree setting.)

With the distance set, switch to the WM-200 setter.  Watch the film on the site associated with this jig.  Set the protrusion of the blade for the angle you want.  Do not change the distance of the bar; change the length of the protrusion to achieve the angle you want.

The back of the TTS-100 has three protrusion lengths for turning tools.  One of these may happen to fit the length you want for your blade.  If so, use it and note it for future reference.  If not, you may make a sharpie line on one of the lengths to correspond with the length you want.  Making a kine of a piece of cardboard or plywood would also work.  Be sure to label it.

When you switch wheels, just set the new wheel to the same TTS-100 setting as the original wheel.  The two point design of the TTS-100 automatically calibrates the universal support bar to the same angle.

The same method works with the leather honing wheel.

Good luck.

Ken 

822
General Tormek Questions / switching between wheels
« on: February 12, 2011, 12:17:53 pm »
In the Woodworking post ("a note to Steve", Jeff made this comment regarding changing the grinding wheel from the general wheel to the 4000 grit wheel:

"If the diameters are different (and they are) you will have to readjust the Universal Support height, but there's no reason to make any adjustments to the jig."

I have been investigating the possibility of using the TTS-100 for setting the height of the universal support bar when sharpening chisels and planes.  Its two point design automatically self corrects for wheel diameter differences.  When using just one wheel, this seemed overkill.  However, it might simplify switching back and forth between different grit (and diameter) wheels, and also with the honing wheel.

Here is how the procedure works"

1)  Using the TTS=100, set the universal support bar to the lower setting (the thirty degree setting).

2)  Set the length of the tool projection from the SE-76 to the correct angle, using either the Angle Master or black marker.  Note this length and make a gage block or cardboard marker.

3) After switching grinding wheels, set the new wheel with the TTS-100 just as you set the first wheel.  The two point alignment system should automatically realign the tool at the original projection length.

Ken
      Reply
      Quote
      Notify

[Ken S]

Jambe,
I know it is frustrating not to get replies about the Multi Tool.  I have never thought it is forbidden to discuss it on this forum.  The forum is Tormek based, and Tormek foots the bill.  However, in my opinion, the Tormek and the MultiTool do different functions, albeit with some crossover.

You are the first person in my limited memory on this forum to mention actually owning a Multi Tool.  Persons posting about the Tormek drill bit jig have the same lack of coverage problem. I don't own a Multi tool.  It looks like a very useful tool. 

In my case, I found an ancient Dayton belt grinder at a nearby yard sale for $25.  The disc sander was missing (still missing); the motor had been rewired with lamp cord; and the pulleys and belt were a basket case.  I rewired the motor and for another $25 replaced the pulleys and belt.  It is no match for a Multi Tool, but is adequate for my needs.

I have found it to be a very useful tool.  The wider belt on the Multi Tool would seem even more useful.  I especially like being able to quickly and easily change belt grits.

I don't think you will find much experienced advice on this forum, but I hope you will post your thoughts on using it.

When Rob was purchasing a dry grinder to augment his Tormek, I recommended a NOrton 3X 40 grit wheel, or similar.  The Tormek excels at sharpening. The dry grinder can remove more metal easily.  I would not cripple the dry grinder by using a fine wheel.  Use the Tormek for the fine stuff.

Do keep us posted.

Ken

[RustD]

Thanks Ton. This really helps a lot. Thank you for doing so much work.

RustD (Steven) 

[wootz]

Hi Ton,

Since I first read your booklet, I couldn't stop admiring your work...
Your application of the cosine rule to Tormek is immaculate.

[Dutchman]

Thanks for the praise 
Ken told me about your post after an e-mail about wooden shoes 

[Lausts]

Thank you Dutchman

As a matematician I can confirm your method and formulas, and as a new owner of my Tormek I can confirm that the method makes a lot of sense. Quick and easy.

Thanks
Laust