Setting accurate grinding angle

[JoeS01]

Hello, is there any way I can set a very accurate angle on my Tormek Supergrind 2000? I prefer to do the hollow grind on this water wheel, and then use the Veritas Mk2 honing jig on my 5000 Japanese water stone for the final hone, but the angles never line up. I know the Veritas jig is quite accurate, having tested the resulting angle, and it is repeatable.
Hoping someone can help

[cbwx34]

Hello, is there any way I can set a very accurate angle on my Tormek Supergrind 2000? I prefer to do the hollow grind on this water wheel, and then use the Veritas Mk2 honing jig on my 5000 Japanese water stone for the final hone, but the angles never line up. I know the Veritas jig is quite accurate, having tested the resulting angle, and it is repeatable.
Hoping someone can help

How are you setting the angle on the Tormek, and how far off is it?

It might have to do with the width of the bevel on chisels...

Take a look at these threads:

Manual touch up of chisels between sharpening and angle issues

Wood chisel sharpening

My .02, it might be easiest to adjust the angle on the Tormek to match what you want on the Veritas at the end... so, for example, if you want the Veritas angle to be 30°, you might have to set the Tormek at 28° or 32°, (or whatever amount it's "off").

Hope that helps... I'm not really a chisel sharpener... just remembered the first thread, (and found the other).

[jeffs55]

I assume that you do not have an angle setter for the Tormek. If it was me and I wanted to duplicate the angle that you get with the water stone this is what I would do. Mark your blade with a marker and sharpen on the stone enough to wear off the marker. Note the amount worn off with the stone. There will be a sharpened area that no longer has marker ink on it. Note the width of this mark with a ruler or caliper even better. Reink the blade and place in the knife jig of the Tormek. Starting with an obviously too steep of an edge place the knife to the wheel and turn the machine on. Note the wear pattern and proceed to lessen the angle of attack till you match the mark made by your water stone. You may even want to turn the wheel by hand to lessen contact with the wheel while it is not in the correct setting. When I say obviously too steep I do not mean 90 degrees to the wheel but just eyeball it so that it is steeper than the angle you are using on the water stone. This should get you within a degree of what you want.

[justonething]

The angle setter is not precise and the setting does not always match that of the MKii honing jig.
Therefore, I think you have to do it by reference. What I mean is that you first need to have a sample plane iron with the exact bevel angle that you want. This plane iron could be something that you have previously ground with your MkII honing jig.
I would use the following steps in first finding the reference measurements.
1. Measure a set distance from the edge of the iron and mark a line on the back of the iron perpendicular to the edge of the blade, as in attached photo No. 1. I choose a 40mm distance from the edge and is marked with a pencil; you can use a different length if you want;
2. Place the blade in the square edge jig SE-77 and line up the front of the jig to the pencil line, and paint the bevel with a felt tip pen, as in photo No.2;
3. Place the jig on the Tormek grinder as you would if you were sharpening, but without turning on the grinder, rotate the wheel by hand while adjusting the height of the UAB, until you see the painted bevel is being rubbed off at the middle. This is when the grinding angle exactly matches that of the existing bevel. You will also notice that the sound changes, as more of the surface of the bevel is in touch with the stone, as in photo No.3;
4. Tighten the UAB first and then test it again to see if nothing has changed, adjust if necessary.
5. Use an outside calliper to capture the distance between the top of the Universal support bar and the top of the adjuster, as in photo No.4. Measure the distance of the opening with the calliper; in my case, it was 40mm. Keep that distance for reference.
6. Measure the circumference of you wheel if it is an SG type or non Diamond wheel;

When you want to get the same exact angle the next time, All you have to do is the mark the pencil line on the back of the blade in the same place (40mm in my case), put it in the jig, and set the height of the USB to the same distance from the adjuster, You will get the same angle as long as the circumference of the stone stays approximately the same.

[Ken S]

Welcome to the forum, Joe.

I bought my Tormek to sharpen my chisels in 2009. Chisels are still my favorite tools to sharpen. Once you get the hang it, the Tormek can sharpen chisels verywell.

For sharpening chisels and plane blades, you really should have a Tormek Anglemaster (WM-200). Although the
Knife People on the forum do not like it, the Anglemaster works very well using the back of a chisel as a reference surface. Here is a good sequence to match your Veritas jig:

Start with a chisel around 3/4" width that you have sharpened with your Veritas jig. Mark the bevel with your Sharpie.
A good starting point is to have the chisel protrude two inches beyond the front of the jig. (This is arbitrary.)
Set the Anglemaster. Match the diameter setting with the diameter of your grinding wheel. Match the angle setting on your Anglemaster with the angle you use with your Veritas jig. with the chisel mounted in your jig and the jig attached to your support bar, turn your grinding wheel by hand enough to grind away a strip of your Sharpie mark.

This works best if you have ground your chisel bevel flat or almost flat with your Veritas jig. If your two angles match, the strip of marker removed should be in the middle of the bevel. If it is not centered, you will need to raise or lower the support bar. 

You may think this is too tedious. However, you should only have to do this once. If you take the time to do this right, it will match your two angle settings. If you are lucky, which is very possible, 30° on your Veritas jig may correspond with the 30º degree setting on the Anglemaster (the WM-200). If the two scales do not match directly, make a label for your Anglemaster worded something like Anglemaster reading - 2° = Veritas reading.Be sure to watch (study) the new Tormek online class on sharpening chisels and plane blades. Here is a link:


https://youtu.be/wMATay8ITE8

Keep us posted.

Ken

[cbwx34]

It would be interesting to know the difference between the Tormek angle and the Veritas Jig angle in the original post, (as well as some chisel dimensions)...

Looking at the "Simple Knife Edge" tab in Gilles "Polishing Angle Calc", (and probably in TormekCalc somewhere), it calculates the "Angle of the Chord", which, in looking at the picture (attached below), should be the angle sharpened on the Tormek to match the Veritas?  (While it says "knife edge", I don't see any parameters that would prevent it from working on a chisel.... if someone could input the chisel measurements, seems like it would tell).  TormekCalc appears to have the data needed to sharpen a chisel with the SE-77.

I think the AngleMaster would give the sharpening angle, which is why it may not match the Veritas Jig?  (I know the simplest solution may what others have said, just use whatever angle matches... but am curious why, as well as find a solution that would be easy to calculate).

(Hopefully, not talking to myself here)... 

[justonething]

I think Tormek's angle-master is a brilliant design, it's so easy to use. However, I found that it will sometimes give a steeper bevel than what you set.  This is particularly true when you are reshaping the bevel of your iron (from a higher bevel to a lower bevel). You set the square edge jig to grind at a particular angle with the angle-master at the beginning of your session. As you start grinding, the angle starts to steepen. When you finish, the bevel angle could be 1° steeper, depending on how much re-shaping you were doing . You will have to use the angle master after you finish to re-check and re-grind if necessary.
Now, customarily 1~2° here and there wouldn't be a problem. But if you are being forced to work at a set angle in the MKII jig. It will be a lot of material to remove if it is too steep.
This situation is not nearly as affected when you use the reference method.

[jvh]

Hello, is there any way I can set a very accurate angle on my Tormek Supergrind 2000? I prefer to do the hollow grind on this water wheel, and then use the Veritas Mk2 honing jig on my 5000 Japanese water stone for the final hone, but the angles never line up. I know the Veritas jig is quite accurate, having tested the resulting angle, and it is repeatable.
Hoping someone can help

Hello,

TormekCalc2 can calculate sharpening data for SE-77 jig - see pictures. But you have to check/change constants (HV, VV, HH, VH) for Supergrind 2000 to get exact results. If you are interested, I can help you.

First picture is validation in parametric CAD. You can see measured protrusion X = 20 mm (from front jig face), grinding angle Δ = 35°, wheel diameter D = 250 mm, height of vertical USB (VUSB) = 103,74 mm, constant HV = 50 mm, constant VV = 29 mm and USB diameter U = 12 mm.

Second one is screenshot of TormekCalc2 , inputs as above, calculated height VUSB is the same as in validation = 103,74 mm.

Third one is SE-77 jig specification. Data is valid for my piece, others may differ by about a tenth of a mm, but it is not so important.


jvh

[cbwx34]

I think, even if the AngleMaster and Veritas were both accurate... the two still wouldn't "match" since, as indicated in the diagrams (this is Jan's)...



... the line of the straight 25°, wouldn't match the grind left by the wheel.  (Might be a good arguement for grinding on the side of the wheel, or just doing all the work on the Tormek?...). 

So, you would have to pick a method of some sort to match the two to your satisfaction (reference method, Sharpie, etc.).

p.s.   Since the bevel is wide enough, it should be easy to match on the stone... wouldn't it be easier just to freehand it?

[Ken S]

The problem is not in the design of the Anglemaster; it is in the way it is used. You could produce the same error using the Veritas jig (no criticism of the jig intended).

A simple experiment will demonstrate this. Set up chisels with both your Veritas jig and the Anglemaster to the same angle. Use a very coarse bench stone with the Veritas jig, say 220. Use your Tormek stone graded coarse. Grind with each for ten minutes. This is removing much more metal than is normally necessary for sharpening. Your original angles , say 25°, will change, perhaps to 28° or 30°. Why is this? If you measure the starting and ending Projection, it is no longer the same.

We do this routinely in other areas. Navigating a boat or a plane, one must compensate for the current or wind.

In your set up doing the sharpening with the Tormek and the polishing with the flat stone, the Tormek is removing the bulk of the metal. The change in Projection occurs in this part of the operation. The Anglemaster does not know if you want to set it for the beginning or final Projection angle. With your 5000 grit polishing stone and Veritas jig, verylittle metal is removed. The Projection remains essentially the same.

Using your Tormek for sharpening (the initial "heavy lifting" of grinding out nicks or resetting bevel angles) is quite logical. Whether you finish with bench stones or the Tormek is a personal preference. Both methods work. My Veritas jig is over twenty five years old. It is the original model, and it served me well. (The newer models are much improved, although the old guy is still quite capable.) It and my Norton water stones have sat on my shelf for ten years. If I needed to sharpen a chisel during a power outage, I would recall them to active duty.

As a practical start, if you want to end up at 25°, try setting your Anglemaster at 23° or 24°. Some initial trial and error may be necessary.

Ken

[micha]

I sometimes also use the Veritas MKII after the Tormek.
It is my understanding that we are talking about adding some sort of (maybe a very slight) microbevel with the Veritas jig, rather than absolutely matching the Tormek angle. For that, the micro-bevel knob on the MKII usually allows for enough adjustment to get there. Am I missing something?

While I like the clarifying theory behind all this (thanks CB and jvh), I would never struggle to use a waterstone for 'repeating' the Tormek's angle exactly. That being said, I know that there are a lot of different personal concepts and that such thoughts can be also considered as heresy. (Hope they won't.)

Mike

[jvh]

I sometimes also use the Veritas MKII after the Tormek.
It is my understanding that we are talking about adding some sort of (maybe a very slight) microbevel with the Veritas jig, rather than absolutely matching the Tormek angle. For that, the micro-bevel knob on the MKII usually allows for enough adjustment to get there. Am I missing something?

Hello,

I think we are talking about deviations in the grinding angle caused by the roundness of the wheel.
This means that if you grind the exact angle at the apex (eg. 20°), the angle at the edge heel will be higher and it depends on the blade thickness. For single bevel grind done with wheel dia 250 mm and 3 mm blade thickness is the angle at edge heel 23.7°.
This can cause the problem with Veritas MKII because it is designed for flat grind and if you set 20° you will grind the edge heel only, because there stays ungrinded material due "wheel roundness". Pictures from Gilles "Polishing Angle Calc" and other posted by cbwx34 illustrate this.

Part of TormekCalc2 is EdgeCalc where you can calculate and see deviations caused by the roundness of the wheel vs flat grind.

The most important is that you get exact angle at the apex but you have to count with ungrinded edge heel material which interferes if you want to grind or hone on flat stones.
You can grind off edge heel, you can start with sharper angle, hone at higher angle or something between.

IMHO generally hollow grind isn't disadvantage because there is no material in the middle and therefore is easier to maintain the edge even on flat stones because you have to grind/hone very few material to get fresh apex.

jvh

[micha]

jvh,

thanks for the explanation, I guess now I've seen the light, or at least some of it.

Am I right in thinking this is a problem especially before applying a hollow grind for the first time? And that a first grind at a slightly more acute angle would give enough clearance on the heel to allow the apex to make contact with the wheel? Then subsequent measuring might be done with the very apex touching the stone and should thus be more precise, possibly reducing the inconsistencies with the MK II.

Mike

[Ken S]

As a follow up to my earlier post, I watched the Tormek online chisel sharpening class again. (I have actually watched it several times and continue to learn more each time.) Tonight was different. Almost all of my screen time is with my ipad. Tonight my grandson "liberated" my ipad. Several years ago I replaced my photo darkroom with a macbook pro.
I watched the Tormek online class on the macbook. What a difference! The larger screen was tack sharp. The video was well shot, so the larger screen really showed the information.

If you guys have not yet watched the online classes, they are must see.

Ken

[JoeS01]

Many thanks to all for this incredible discussion. Well done!
I  have found the Tormek online chisel sharpening class referred to above, and noticed that the AngleMaster has a flat base that sits on the chisel back when setting the angle. On my old Supergrind 2000 the bottom of the piece that sits on the back of the chisel is curved, and I  am never sure of the exact position where it should sit on the chisel.
Should I  get a new AngleMaster to start with?