Tormek Community Forum

In the Shop => General Tormek Questions => Topic started by: Ken S on May 22, 2019, 06:31:26 PM

Title: flat grinding using the edge of any grinding wheel (early stages)
Post by: Ken S on May 22, 2019, 06:31:26 PM
Quite a while back, someone (Elden, I think) brought up the possibility of flat grinding with the Tormek.This is actually how the Tormek molding cutter jig works. Ever since then, I have been fascinated with the possibility of doing this. I think I have finally discovered a workable method. Unlike using the side of the diamond wheels, this should work with any grinding wheel using the edge of any grinding wheel.

Referring to the SG, the handbook states that the out of true tolerances for the edge of the wheel are tighter than the out of true tolerances for the side faces of the wheel. (The side tolerances for the diamond wheels are presumably tighter.) However, the handbook also states that  the trueness of the SG can be improved by using the truing tool. The initial tighter tolerances of the edge of the wheel, plus the ability of using the TT-50 truing tool with the SG led me to seek a flat grinding solution with the edge of the SG.

Here is my solution:

First we start with a freshly and carefully trued SG.

Next, a Knife Grinders VFB (vertical front base) is placed in the vertical sleeves.

A Tormek MB-100 Multi Base is placed in the Knife Grinders VFB from the front side.

I placed my Extended Support Bar from Robin Bailey into the MB-100. The support bar should be oriented to be level and slightly above and to the outside of the grinding wheel. I set this up using the Torlock platform to sharpen the large Alan Lacer skew. It should work with other jigs as well.

I started out using the standard US-105 support bar. This may work fine. I switched to the larger support bar to have plenty of working room. The newly redesigned Tormek US-400 will also provide this extra working room, as well as a microadjust.

This method should provide accurate flat grind to the Tormek with any grinding wheel. I will post as I progress with it.

Ken
Title: Re: flat grinding using the edge of any grinding wheel (early stages)
Post by: RichColvin on May 23, 2019, 02:17:33 AM
Ken asked me to post these for him.
Title: Re: flat grinding using the edge of any grinding wheel (early stages)
Post by: Ken S on May 23, 2019, 03:52:46 AM
Thanks, Rich.
Ken
Title: Re: flat grinding using the edge of any grinding wheel (early stages)
Post by: RickKrung on May 23, 2019, 05:14:28 AM
Very ingenious, Ken.  Nice going. 

The Tormek is regarded as slow by many.  Grinding on such a small surface area as with this setup will be even slower.  If one has already put the primary bevel on the traditional way, flattening it with your setup looks like a great way for those without the diamond wheels with abrasive on the flat side.

It also occurs to me that you would want to move the platform occasionally to keep from grinding a groove in the stone. 

Rick
Title: Re: flat grinding using the edge of any grinding wheel (early stages)
Post by: Ken S on May 23, 2019, 11:39:10 AM
"Very ingenious, Ken. Nice going." Thanks for the compliment, Rick. I modestly happen to think it is ingenious, too. What I don't know is whether or not it is practical. Frankly, for many (most) tools, I don't see the benefit of a flat grind over the miniscule hollow grind of an eight or ten inch grinding wheel. If this new found hollow grind issue involved any company except Tormek, I would be tempted to call it a marketing ploy. :) In fairness to Tormek, we are still awaiting a good explanation of the benefits of flat grinding.

The reason I doubt the practicality of my set up is that a nearly identical, if somewhat hollow ground, result can be obtained with just the standard issue support bar and Torlock platform. I agree with you, Rick, that this simpler arrangement would probably cut faster. Also, the extra hardware involved can be costly. I happen to already have the pieces/parts. I don't believe I would have purchased them just for this project.

Flat grinding may be essential for some tools. I will probably classify this project as "future possible."

Ken

ps This set up demonstrates the superior holding power of Tormek's patented Torlock.
Title: Re: flat grinding using the edge of any grinding wheel (early stages)
Post by: RichColvin on May 23, 2019, 02:20:11 PM
Quote from: Ken S on May 23, 2019, 11:39:10 AM
I don't see the benefit of a flat grind over the miniscule hollow grind of an eight or ten inch grinding wheel.

Ken,

I also think this is a great demonstration of the Tormek's flexibility; however I also agree with your doubt about the benefit of flat grinding tools. 

I've only encountered one situation where hollow grinding is a not desired, and that is with certain wood carvers' preference for carving knives (I'm not good enough for that to be an issue for me).  But, for them, this may be a really good option.  As their tools are typically high carbon steel, I would expect they will use the SG or SJ grindstone rather than investing in the diamond wheel(s).  So, your exploration of this approach is to be commended.

Kind regards,
Rich
Title: Re: flat grinding using the edge of any grinding wheel (early stages)
Post by: RickKrung on May 23, 2019, 04:40:09 PM
Regardless of its practicality, I really like the thinking and execution of the novel approach and it provides a solution that every Tormek user can use if the flat grind is important and they are willing to take the time.  A flat grind is meaningless to me as I don't have or use any tools for which it would make a difference. 

Rick
Title: Re: flat grinding using the edge of any grinding wheel (early stages)
Post by: Josu V on May 26, 2019, 08:42:34 PM
I think this is agood idea if flat grinding is a priority..

But I think that this configuration is very sensitive at advance velocity of the knive/tool.
With this configuration you must be very constant with the advance speed in order to make a perfect bevel.
if you decrease advance speed at any moment, the grinding wheel will spend more material and the bevel looks no good.

Sorry for my english; perhaps I don“t find the right words to explain that I think.

Regards.
Title: Re: flat grinding using the edge of any grinding wheel (early stages)
Post by: Ken S on May 27, 2019, 02:19:05 PM
Josu,

I agree that this flat grinding method requires skill to work right. However, even conventional knife sharpening requires skill to do a good job.

Never apologize for your English. We are an international forum. English just happens to be our most commonly used language. Many of our best posts have been made by members whose primary language is not English. Your thoughts are more important than linguistic details.

Ken

ps Just out of curiosity, what is your first language?
Title: Re: flat grinding using the edge of any grinding wheel (early stages)
Post by: Josu V on May 28, 2019, 05:57:31 PM
Thank you very much for your words, Ken.


My first language is Spanish. (Basque Country in the North of Spain).

Regards
Title: Re: flat grinding using the edge of any grinding wheel (early stages)
Post by: Ken S on May 29, 2019, 12:32:20 AM
Interesante, Josu. As a student, I lived in Barcelona during the spring of 1969. Spanish was a second language, both for me and the local students, who spoke Catalan.

recuerdos,

Ken
Title: Re: flat grinding using the edge of any grinding wheel (early stages)
Post by: Josu V on May 30, 2019, 06:20:15 PM
Ja, ja, ja... How small is the world. Beautiful city; I have very good friends in Barcelona. (there is about 700Km between Basque Country and Barcelona)

Saludos  :)