Bevel Angle accuracy

[Hugh Proudman]

Hi,

I am writing to ask for some help. I am sharpening a batch of woodworking chisels for a school - using whichever Tormek is free that day. Sometimes a T4 and sometimes a T7.

I am able to produce nice sharp bevels that are square. The chisels are suitable for the students to use.

However, the bevel angle that I have produced does not match the angle that I set on the AngleMaster. I am aiming to create a 25 degree bevel, but am consistently creating one at 30 degrees. In order to grind a 25 degree bevel, I find that I need to set the AngleMaster to 20 degrees.

This is a repeatable process, so in a sense this doesn't matter that much; just do what works.

However, as this is in a school I would like to understand what I am doing wrong so we can ensure the students don't learn my mistakes.

I have been careful to set the stone diameter on the AngleMaster, and have had other people watch my approach - to see if they can spot something that I'm doing wrong. Nothing stands out.

I have also watched the excellent Tormek Chisel sharpening class - part 3. I can't spot anything obvious that I'm doing wrong. One difference in my approach is that I tend not to use the Micro Adjust on the Universal Support. Instead I just edge the chisel backwards or forwards in the Square Edge Jig - till it matches the Angle Setter on the AngleMaster.

I will try using the Micro Adjust next time but would be grateful for any tips and suggestions on what I'm doing wrong - particularly if anyone else has experienced this problem.

Many thanks, Hugh

[Dutchman]

From the first use I also had problems with the anglemaster. Clumsy and inaccurate.
Therefore, I designed a simple and accurate method to set the angle, based on measurement of distances.
See https://forum.tormek.com/index.php/topic,1849.0.html
Various spreadsheets were then developed, based on that method.
However, Tormek has finally responded with the development of a new angle adjuster, the KS-123.
See my testreport on https://forum.tormek.com/index.php?msg=40399

[tgbto]

Although I concur with @Dutchman wrt the tool's clumsiness, the AngleMaster should be well suited to setting/measuring an angle on chisels. A systematic 5° difference is especially intriguing.

Can you maybe post a picture of :
- How you set your angle using the WM 200, taken from the side so we can see the markings on the WM-200, where the plastic contact the wheel and if there is any gap between tool and the back of the chisel ?
- How you measure your angle ?

Cheers,

Nick.

[Ken S]

Welcome to the forum, Hugh.

Let me take two guesses, hopefully favoring the scientific portion of SWAG (Scientific Wild Ass Guesses).

First: When you use the Anglemaster, is the angle pointer positioned so that the bottom touches the grinding wheel?

Second: Since the 5° error seems consistent, especially since these are school machines, is it possible that your pointers may be worn. We have had a few posts where these are the problem. I suspect that this wear occurs from measuring while the machine is still running, but that's just a guess.

Third, I would suggest that you email support (support@tormek.com) The two pointers are both available as replacement parts. I do not speak for Tormek; however, I would not be at all surprised if Tormek gifted you the spare parts. Support is very experienced and dedicated.

Please keep us posted.

Ken

[Dan]

.....How you measure your angle ?

Cheers,

Nick.

To me, this question is very important. it may be a good part of getting to solve your angle problem. It took me a while (mentally!) to get what was happening with the finished angle. What confused me was the curve on the bevel.

In order to measure correctly, we need to measure just the angle at the bevel tip (even though it is not easy) as that is where the cutting edge is.
If we measure over the whole bevel, the angle will be greater as the concave curve sweeps up away from the tip. Not sure if it is 5° difference or not but that will also change if you are using a T8 or T4 due to the wheel diameter difference.

The second picture in this post shows what I mean.
https://forum.tormek.com/index.php?msg=31650

I know you are using the anglemaster now but I must say that I ended up using the Calcapp to get the desired angle and I have to say I use it for all knives, chisels and planes now. It is extremely accurate. I haven't used the AngleMaster for a very long time.

https://connect.calcapp.net/?app=qq0pg0#/

Big thanks to member cbwx34n for this.

Danny