Difference between two methods for angle adjustment

[Sharpco]

There are two ways to adjust the knife grinding angle.

1. Turn the stop of the jig.
2. Turn the Micro Adjust

Do the two produce exactly the same result?

For example, when creating a double bevel(grinding at two angles per side) on a knife with heavy curves, both of them make a constant grinding surface?

[Jan]

Yes, both ways will produce the same result.

Jan

[cbwx34]

Yes, both ways will produce the same result.

Jan

Jan...

Do you have the specifics of how much difference in angle change there is for a rotation (or how much rotation to make a 1° change) for each method?  I think you've posted it before... be nice to have in one convenient location.

(I think you have this info... if not nevermind).   

Edit to add:  In thinking about it... they may produce a different result... since changing the distance of the stop on the jig... will change the pivot distance?  (May not matter if the change is small).   Hadn't thought about it until now....

[Jan]

In a typical Kenjig configuration (stone diameter 250 mm, projection length 139 mm and bevel angle 15°) one turn of the adjustable stop will change the bevel angle by circa 1.5°.

One turn of the micro-adjust will change the bevel angle by circa 1°.

The thread pitch at the knife jig is 2.5 mm while at the micro-adjust only 1.5 mm.

For the bevel angle setting it does not matter what way we use.

Jan

P.S.: CB, you are correct, when sharpening the belly or tip, than the bevel angle may slightly depend on the USB – stone distance.

[cbwx34]

In a typical Kenjig configuration (stone diameter 250 mm, projection length 139 mm and bevel angle 15°) one turn of the adjustable stop will change the bevel angle by circa 1.5°.

One turn of the micro-adjust will change the bevel angle by circa 1°.

The thread pitch at the knife jig is 2.5 mm while at the micro-adjust only 1.5 mm.

For the bevel angle setting it does not matter what way we use.

Jan

P.S.: CB, you are correct, when sharpening the belly or tip, than the bevel angle may slightly depend on the USB – stone distance.

Thank you!

[Sharpco]

P.S.: CB, you are correct, when sharpening the belly or tip, than the bevel angle may slightly depend on the USB – stone distance.

If I turn the stop of the jig instead of the Micro Adjust to change the 2 degrees, is the difference in the bevel angles of the belly & tip compared to when using Micro Adjust?

[Ken S]

Excellent question. I agree completely with the replies. I would add that when I was developing the kenjig concept I originally used chisels and planes. (The concept works well with many kinds of tools.The limits are our imaginations.) I set the Distance between the universal support and the grinding wheel using the TTS-100. It gave me a fixed distance. I set the tool projection using the Anglemaster. It was slower than just spinning the microadjust. The advantage is that it is only done one time. I marked the Projection on a piece of tape in one of the slots of the TTS-100. Every blade set to thst angle since then has bern fast to set and accurate. Tormek has an outstanding tool in the TTS-100. I could never understand why they did not expsnd the idea beyond turning tools.

I use whichever variable is easiest in the situation.

Ken

[cbwx34]

If I turn the stop of the jig instead of the Micro Adjust to change the 2 degrees, is the difference in the bevel angles of the belly & tip compared to when using Micro Adjust?

This is an interesting question.  Initially, I would think there's no difference, until I thought of the pivot distance changing.

I did a bit of a dry run, just to see what popped up.  I set an angle of a knife at 17 deg. (all angles set/checked with the AngleMaster), and drew a LOC (Line of Contact) on the stone.  Then I adjusted the angle to 20 deg with both methods (3 turns with the MicroAdjust / 2 turns with the Jig Stop adjust), and drew a 2nd LOC for each.

With both methods the AngleMaster showed 20 deg.  But, there was about a 4mm difference between the 2 LOC drawn at the 2 20 deg. settings.  I could also see a slight difference in how the knife tracked in relation to their respective LOCs.

My thought is, it's not significant.  A good check would be to compare Sharpie marker removal, (but ran out of time... you might consider giving it a try).

Practically, probably not going to matter much.   

[RickKrung]

If I turn the stop of the jig instead of the Micro Adjust to change the 2 degrees, is the difference in the bevel angles of the belly & tip compared to when using Micro Adjust?

This is an interesting question.  Initially, I would think there's no difference, until I thought of the pivot distance changing.

I did a bit of a dry run, just to see what popped up.  I set an angle of a knife at 17 deg. (all angles set/checked with the AngleMaster), and drew a LOC (Line of Contact) on the stone.  Then I adjusted the angle to 20 deg with both methods (3 turns with the MicroAdjust / 2 turns with the Jig Stop adjust), and drew a 2nd LOC for each.

With both methods the AngleMaster showed 20 deg.  But, there was about a 4mm difference between the 2 LOC drawn at the 2 20 deg. settings.  I could also see a slight difference in how the knife tracked in relation to their respective LOCs.

My thought is, it's not significant.  A good check would be to compare Sharpie marker removal, (but ran out of time... you might consider giving it a try).

Practically, probably not going to matter much.   

This makes sense to me.  By changing the stop or microadjust, you are changing the orientation and position of the USB and jig, but maintaining the bevel angle.  It makes sense that the LOC would change on the wheel.  If it didn't, you wouldn't have the same bevel angle.

Rick

[cbwx34]

This makes sense to me.  By changing the stop or microadjust, you are changing the orientation and position of the USB and jig, but maintaining the bevel angle.  It makes sense that the LOC would change on the wheel.  If it didn't, you wouldn't have the same bevel angle.

Rick

My writing wasn't very clear... what I meant was, there was a difference between the 2 20° LOCs lines.  (See attached pic.)

[RickKrung]

This makes sense to me.  By changing the stop or microadjust, you are changing the orientation and position of the USB and jig, but maintaining the bevel angle.  It makes sense that the LOC would change on the wheel.  If it didn't, you wouldn't have the same bevel angle.

Rick

My writing wasn't very clear... what I meant was, there was a difference between the 2 20° LOCs lines.  (See attached pic.)

That is how I took your statement(s). It still makes sense to me, IF, you are saying even thought the LOC differs for the two 20 deg knives, their angles are in fact still both 20 deg. 

Rick

[wootz]

There are two ways to adjust the knife grinding angle.

1. Turn the stop of the jig.
2. Turn the Micro Adjust

Do the two produce exactly the same result?

For example, when creating a double bevel(grinding at two angles per side) on a knife with heavy curves, both of them make a constant grinding surface?

Maybe the way I do similar butcher knives with widened tip will help you - https://forum.tormek.com/index.php?topic=2589.msg20501#msg20501

[Sharpco]

Maybe the way I do similar butcher knives with widened tip will help you - https://forum.tormek.com/index.php?topic=2589.msg20501#msg20501

Thank you Wootz.

How about using the following template?
https://forum.tormek.com/index.php?topic=2654.msg14154#msg14154

[cbwx34]

This makes sense to me.  By changing the stop or microadjust, you are changing the orientation and position of the USB and jig, but maintaining the bevel angle.  It makes sense that the LOC would change on the wheel.  If it didn't, you wouldn't have the same bevel angle.

Rick

My writing wasn't very clear... what I meant was, there was a difference between the 2 20° LOCs lines.  (See attached pic.)

That is how I took your statement(s). It still makes sense to me, IF, you are saying even thought the LOC differs for the two 20 deg knives, their angles are in fact still both 20 deg. 

Rick

In my thinking, if I'm making the same distance adjustment with each method... I should end up at the same location on the stone (at least on the straight portion of the blade)... so not ending up there, may mean there's a slight difference in how the blade would track, especially in the belly to tip area.  (But I'm not sure if Jan's answer is resulting in the same distance change... or if he calculated how much change is needed for a 1° change, separately with each method).

[cbwx34]

Maybe the way I do similar butcher knives with widened tip will help you - https://forum.tormek.com/index.php?topic=2589.msg20501#msg20501

Thank you Wootz.

How about using the following template?
https://forum.tormek.com/index.php?topic=2654.msg14154#msg14154

If you're trying to match the "belly to tip" area with the rest of the blade, the easiest way I've found, (currently anyway), if you're using the SVM-45... is to just draw a line on the stone, set the angle on the flat part, then, with the stone not moving, move the knife across like you would sharpen it, and make sure all parts stay near the line.  After a bit of practice, you can get an idea of where most knives should be clamped without any aid... and quickly do this for knives that may need it (for example have a more pronounced belly).  This assumes you "lift and pivot" the knife, keeping the edge approximately perpendicular to the stone, and are not just lifting the handle... which requires more attention placed on the location of the knife in the jig.

And as always... Sharpie marker is your friend.