measuring reference points

[Ken S]

 When I first developed the kenjig, I used the distance between the top of the universal support bar and the grinding wheel as my reference for determining the Distance. At the time, I used my T7. When I acquired my T4, I just made a new kenjig with the Distance groove cut for 200mm diameter. When I added my T8, I just used my original T8 kenjig as is.

Some of the more recent programs use the distance between the top of the universal support bar and the frame instead of the grinding wheel. As such, the T7,T4, and T8 require separate measurements.

My question, and it is just an honest question rather than advocating one method, is what is the reason for measuring using the frame rather than the grinding wheel?

Ken

[cbwx34]

When I first developed the kenjig, I used the distance between the top of the universal support bar and the grinding wheel as my reference for determining the Distance. At the time, I used my T7. When I acquired my T4, I just made a new kenjig with the Distance groove cut for 200mm diameter. When I added my T8, I just used my original T8 kenjig as is.

Some of the more recent programs use the distance between the top of the universal support bar and the frame instead of the grinding wheel. As such, the T7,T4, and T8 require separate measurements.

My question, and it is just an honest question rather than advocating one method, is what is the reason for measuring using the frame rather than the grinding wheel?

Ken

I think Dutchman has said several times that measuring to the wheel is the best, most accurate option.  I think measuring to the frame may be a bit easier to learn and teach others, but as you pointed out, it makes the calculator "machine specific" and also opens up more points for error to occur.  (Still more than sufficient for the process in most cases though).  So, personal preference plays a part I suppose.

I've worked with both... I prefer measuring to the wheel, mainly because it's the most "universal"... I can use it in a variety of positions or machines... no additional measurements needed.

[Hannsi1957]

Thats easy to answer Ken.......
Only another way to measure, at the end if u measure correct u get the same Toolbarhight.
So what 

Cheers Hanns

[Dutchman]

Thats easy to answer Ken.......
Only another way to measure, at the end if u measure correct u get the same Toolbarhight.
...

"another method" is not a "reason"! Why would you use a different measure if it only adds sources of error?

[jvh]

"another method" is not a "reason"! Why would you use a different measure if it only adds sources of error?

Hello,

measuring and setting "KenJig" dimension is IMHO not very user friendly (I mean measuring and setting any value with caliper or similar standard tool. Setting a fixed value using a distance pad (KenJig), on the other hand, is very easy.

Measuring height of the USB from defined measuring point is very easy, quick and precise with standard caliper.

And now we are back again on setting of constants as I wrote in TormekCalc² topic. You can set them very precisely using "KenJig" - use measured distance pads (low range / high range), check the calculated height of USBs and make constants correction to get calculated values as close as possible to measured values (see also FAQ in TormekCalc²). Warning! You will need decimals to be succesful.   It can take some time but, again, this is one time job only (for each machine).

If you do it right, you will supress sources of errors. Not completely, I know, but IMHO USB's hight measurement provides better accuracy/consistency which balances mentioned disadvantages. Another question is, of course, how accurate you work with and what is enough for you.

Last but not least, I work with both systems and both have pros and cons for me. I'm glad we can use both, let the user choose the one which is more suitable for him...


jvh

[Gilles]

Hello
As a beginner, I have tried both methodologies: distance to stone and USB height, measured with a caliper. I have found that it was easier with the USB height.
At that time, i did not realize that the distance to stone was more universal.
What I found difficult with the distance to stone is to have the caliper in the direction of the stone center. On this forum, I have found good ideas with elastic strap between the USB and the center of the stone.
Sorry Ken, I have not already try your Kenjig, due to lack of time but I will.

Gilles

[Ken S]

Interesting answers.Thank you.

"There are many roads going to Dublin." I suppose many cultures have a saying to express the concept that many things can be done in multiple ways. In my case, Dutchman has always been my mentor in this. I have used his method for long enough that it has become second nature. It is fast and accurate, and it suits my needs.

I am aware that my needs are less stringent than some other forum members. I sharpen my own primarily kitchen knives. I can choose my own bevel angles without having to please a customer. I have standardized on 15° per side, although I am gradually moving toward switching to 12°. I make no effort to achieve sub 50 BESS.

I would not impose my preferences on other sharpeners.

lf, as Hanns states, using the frame instead of the wheel as the reference point is "another method", the measure to the grinding wheel method seems more simple and direct, at least for my needs.

JVH, I agree with you that initial set up of a kenjig is not especially user friendly. Initial modification of my TTS-100 for the initial chisels and plane irons is also not especially user friendly, either. As you correctly note, after the kenjig is set up, operation is fast and easy. A digital caliper is definitely the go to tool for making different readings. The kenjig is designed to work like a gage block. IMHO, for repeating the same measurement, my simple "gage block" kenjig is my go to tool.

Gilles, please read the linked pdf. It explains how the kenjig works. I find it much easier to use for repeated same readings against the grinding wheel. Sorry, I tried to just copy the link, but copied all eight pages. Do a google search for "kenjig instructions". You will find it.

Interesting discussion, everyone.

Ken

[wootz]

4-5 years ago when developing our software, we chose measuring to the Tormek housing rather than to the wheel for 2 reasons:
- dropping a perpendicular from the universal support to the flat of the Tormek housing is more easy and accurate than to the wheel;
- we use a depth probe for measuring the distance, and poking the calipers' depth probe into the grinding wheel damages the probe.

And when later we developed our Frontal Vertical Base and extended our software to the Tormek honing wheel, felt wheels, and to paper wheels, we saw that ours was the right approach.
It would be even more difficult to accurately measure a perpendicular to the honing wheel.

All that said, without Dutchman's genius nothing would be possible. Even though prof. Verhoeven gave first formulas for setting grinding angle on Tormek, it was Ton Nillesen from Netherlands, who gave us all the detailed trigonometry of Tormek. We only computerised our version of it.
Ton showed everyone the way.

[Jan]

Five years ago I have modified the Starrett combination square for easy setting of the USB. I use it mainly for setting the top USB – stone distance, but it can be used also for setting the USB height above the Tormek housing.

The 12 mm Al sleeve is attached to the body of the combination square. The sleeve offsets the position of the universal support with respect to the zero on the ruler. This offset is compensated by the contact block made of two Al plates of trapezoidal shape attached to the square head.

I use it every day.

Jan

[cbwx34]

4-5 years ago when developing our software, we chose measuring to the Tormek housing rather than to the wheel for 2 reasons:
- dropping a perpendicular from the universal support to the flat of the Tormek housing is more easy and accurate than to the wheel;
- we use a depth probe for measuring the distance, and poking the calipers' depth probe into the grinding wheel damages the probe.

And when later we developed our Frontal Vertical Base and extended our software to the Tormek honing wheel, felt wheels, and to paper wheels, we saw that ours was the right approach.
It would be even more difficult to accurately measure a perpendicular to the honing wheel.

All that said, without Dutchman's genius nothing would be possible. Even though prof. Verhoeven gave first formulas for setting grinding angle on Tormek, it was Ton Nillesen from Netherlands, who gave us all the detailed trigonometry of Tormek. We only computerised our version of it.

Your posts should now come with a warning... like the ones in an infomercial.  They are simply marketing.  I doubt you can prove that it is "more accurate"... only that it works better for you.  (But I digress...).


I "flipped" the caliper... instead of using the "depth probe", used it like this...



... I found it worked better for me, and actually was more accurate measuring to the wheel than the point of the other end. Studies have shown this was the right approach.   

[RickKrung]

...snip...
At that time, i did not realize that the distance to stone was more universal.
What I found difficult with the distance to stone is to have the caliper in the direction of the stone center. On this forum, I have found good ideas with elastic strap between the USB and the center of the stone.
...snip...
Gilles

I also found it inconvenient to measure the distance to the stone - until turned on to the use of a rubber band (elastic strap) stretched between the USB and wheel axle.  While I am extremely facile with calipers, I find them awkward to use in measuring to the stone, for at least two reasons: 1) the length and weight of the caliper body/head above/beyond the USB makes aligning the depth rod awkward and 2) the relatively narrow width of the main scale/beam barely reaches the centerline of the USB bar.  Plus, I do not like touching grindstones with parts of my precision measuring tools due to the risk of "altering" their dimensions. 

I prefer the use of a woodworker's "marking gauge" for this purpose, both when measuring to the stone and to the machine case.  It has a wide head that easily spans the USB bar and when in full extension to reach the stone or case, nearly all the weight is at or between the USB and measurement point, so the balance is much more within the working area.  I use two, however, one for setting projection distance and one for setting the USB distance.  I replaced the marking knife discs that come on these sorts of marking gauges, in both cases, I replaced the rod (5/16" dia. stainless steel).  In the case of the gauge for setting projections, I added a fender washer on the end of the rod for better alignment with the jig collar.  (Note that the brass base plate of the gauge is what contacts the knife edge, not the SS washer.)

I use calipers to set the distances for these modified marking gauges, which is easier to do "free-hand", away from the machine and then use the gauge to set the USB distance.  I use this same procedure when setting these marking gauges when using them a intended, for making wood pieces during woodworking.

Kinda got to rambling about the use of these gauges.  My main point was I like using the rubber band as a guide for setting the distance to the stone, regardless of the tool used to set the distance. 

Rick

[Jan]

Rick, CB, I like your solutions!

Sometimes I use my knife setter inspired by the Tormek jig TTS-100. It is designed for projection distance 139 mm and different grinding angles. The shown jig is made of two Al plates and four small ball bearings.

It works for all wheel diameters and both grinding directions. All that is needed is to generalize this concept to variable projection distance.

Jan

[wootz]

Your posts should now come with a warning... like the ones in an infomercial.  They are simply marketing.  I doubt you can prove that it is "more accurate"... only that it works better for you.  (But I digress...).

I've had enough of this gentleman. Unless cbwx34 is banned from the Tormek forum, I am not posting any more.

[cbwx34]

I've had enough of this gentleman. Unless cbwx34 is banned from the Tormek forum, I am not posting any more.

Why, does the truth hurt?

You're posting info that's unsupported, a software calculator that many say is "broken", and you won't respond to anyone's questions.... claiming it's proprietary (even though it's really not anymore, or you could answer without giving the details)... instead just telling people to see for themselves and that you're right and they're wrong, or just ignoring it.

A forum is for an exchange of ideas, not to come and make statements stating or implying that your way is "right", others are wrong, and providing nothing for proof, or to just make posts that now basically just support your business.  I think it's fair to point it out... (I'm just blunt about it). 

Why not just respond to the questions that come up, with more of a response than, I tested and it's right, or ignoring it?  That's what a forum is for, (and you use to do it).  (And I'm not the only one asking....).

p.s.  And to be fair, I've tried several times to address some of this privately, and you wouldn't respond to that either.

[Ken S]

I am aware of this unfortunate situation. I had no idea this would turn ugly; I regret starting the topic. I will be locking the topic and make a decision within a day or two.

Ken Schroeder, Moderator