Angle setting on thin knives

[RickKrung]

Reading the manual section on "Thin Knives", diagrams on angle setting using the Angle Master depict the thin knife as having parallel sides, except for the cutting edge.  That is not what my knives have.  Instead they are angled.  A statement attributed to Leatherman, regarding their multi-tool knives stated the angle of the main blade is 9 deg. and the cutting edge 32 deg. (IIRC).  The manual seems to indicate that the bevel angle (cutting edge) can be set directly off of the blade side, but that ignores the angle of the blade sides.  Doesn't one have to subtract half the angle of the blade in order to get the correct angle for setting on the Angle Master? 

In the case above, it would be half of 32 deg. (16) and half of the blade angle (4.5) for a setting angle for the Angle master of 11.5 deg.?

Thanks,

Rick

[cbwx34]

Reading the manual section on "Thin Knives", diagrams on angle setting using the Angle Master depict the thin knife as having parallel sides, except for the cutting edge.  That is not what my knives have.  Instead they are angled.  A statement attributed to Leatherman, regarding their multi-tool knives stated the angle of the main blade is 9 deg. and the cutting edge 32 deg. (IIRC).  The manual seems to indicate that the bevel angle (cutting edge) can be set directly off of the blade side, but that ignores the angle of the blade sides.  Doesn't one have to subtract half the angle of the blade in order to get the correct angle for setting on the Angle Master? 

In the case above, it would be half of 32 deg. (16) and half of the blade angle (4.5) for a setting angle for the Angle master of 11.5 deg.?

Thanks,

Rick

You're correct that you need to make the adjustment... but you need to adjust the other way.  So, in your example, if you want to sharpen at 16 deg. per side, and the blade is tapered 4.5 deg., I would set it at 20 or 21 deg. (I wouldn't worry about the 1/2 deg.... just document what you use for future reference).

I would also mark the edge with a Sharpie marker, and make sure you're removing metal where you want.  (Manufacturer numbers and reality are often two different things).

[Ken S]

Rick,

The marker method works well. I recommend a different procedure with the Anglemaster for all knives.

First, place your knife in the jig with the adjustable stop set screwed about in the middle (not critical).

Lay the jig on a piece of cardboard with the adjustable stop butted against one edge of the cardboard.

Mark a pencil line at the edge of the blade. This will give you the Projection of the knife blade in the jig.

Remove the knife from the jig. Place two thicknesses of gift cards or something similar in the jig. You want a flat surface approximately .060" (1.25mm) thick. Adjust the jig so that the Projection of the gift cards equals the line drawn by the knife Projection. I call this a Substitute Target. The thickness automatically centers it for the thickness of the Tormek knife jigs. It also provides a much needed flat (and parallel) platform for the Anglemaster.

While this technique is not in the handbook, it is part of the forum moderator's playbook. Try it.

Ken

[RickKrung]

You're correct that you need to make the adjustment... but you need to adjust the other way.  ...

I would also mark the edge with a Sharpie marker, and make sure you're removing metal where you want.  (Manufacturer numbers and reality are often two different things).

Wow.  I struggled with this one, about increasing the angle.  Took me a while.  Went to my CAD program and drew it out, but that didn't make it for me.  It was in staring at the diagram and visualizing the blade angle and imagining aligning the Angle Master flat to the blade.  It is elevated relative to a parallel line, making the AM move to a high angle position.  Thanks.

I do use a Sharpie on all the edges, including drills.  Really helps. 

Rick

[cbwx34]

You're correct that you need to make the adjustment... but you need to adjust the other way.  ...

I would also mark the edge with a Sharpie marker, and make sure you're removing metal where you want.  (Manufacturer numbers and reality are often two different things).

Wow.  I struggled with this one, about increasing the angle.  Took me a while.  Went to my CAD program and drew it out, but that didn't make it for me.  It was in staring at the diagram and visualizing the blade angle and imagining aligning the Angle Master flat to the blade.  It is elevated relative to a parallel line, making the AM move to a high angle position.  Thanks.

I do use a Sharpie on all the edges, including drills.  Really helps. 

Rick

The easiest way I figured it out... was to take a knife that had a taper, but had a flat near the heel, set it up on the Tormek at XX deg. on the flat part, then moved it to a tapered portion of the knife... to see that the AngleMaster went to the higher setting to maintain the same angle.  (Like you, in my head, it seems it should go the other way). 

[RickKrung]

Rick,

The marker method works well. I recommend a different procedure with the Anglemaster for all knives.

First, place your knife in the jig with the adjustable stop set screwed about in the middle (not critical).

Lay the jig on a piece of cardboard with the adjustable stop butted against one edge of the cardboard.

Mark a pencil line at the edge of the blade. This will give you the Projection of the knife blade in the jig.

Remove the knife from the jig. Place two thicknesses of gift cards or something similar in the jig. You want a flat surface approximately .060" (1.25mm) thick. Adjust the jig so that the Projection of the gift cards equals the line drawn by the knife Projection. I call this a Substitute Target. The thickness automatically centers it for the thickness of the Tormek knife jigs. It also provides a much needed flat (and parallel) platform for the Anglemaster.

While this technique is not in the handbook, it is part of the forum moderator's playbook. Try it.

Ken

Thanks Ken.  That is a very nice, straight forward and fast way of dealing with it.  I found the scale from a mini-Starret adjustable square to be almost exactly the width of the blade I wanted to sharpen (the one with the bevel edge at 32 deg) and inserted it to the same extent that the blade would be held (first photo).  Then I set the Angle Master and use it to set the angle for the blade, at 16 deg.  (second photo).  I am wondering if the lack of a point on the scale changes the angle much.  If so, it might be good to add a degree or two to compensate. 

Great method.

Thanks,

Rick

[cbwx34]

I am wondering if the lack of a point on the scale changes the angle much.  If so, it might be good to add a degree or two to compensate.

If you mean lack of a tip?... shouldn't make a difference... you're just measuring the straight part of the blade.  You do have to position the blade properly in the clamp to correctly sharpen the tip (as shown in the manual).

The thickness of your square might make a difference though... not sure how much.  Also, the measurement should be taken as close to the stone as possible... in your picture it looks like you're ½ way up the side of the scale.  (Measuring on a curve sorta changes the rules of what I was used to, if that makes sense... my experience anyway).

[Ken S]

Rick,

Clever use of your Starrett mini square. As an aside, I have a hobby curiosity in measurement and have collected Starrett tools. I still enjoy them, but have stopped collecting.

My original Substitute Target is a flat piece of 1/16" steel. (That's US big box hardware store measurement). I thinned it to 1.25mm (.050") and ground a bevel on one edge. I posted it, including a photo, on the forum. I found the plastic gift cards work well enough and are easier to trim. They are also less expensive than anything Starrett.

Ken

[RickKrung]

I am wondering if the lack of a point on the scale changes the angle much.  If so, it might be good to add a degree or two to compensate.

If you mean lack of a tip?... shouldn't make a difference... you're just measuring the straight part of the blade.  You do have to position the blade properly in the clamp to correctly sharpen the tip (as shown in the manual).

The thickness of your square might make a difference though... not sure how much.  Also, the measurement should be taken as close to the stone as possible... in your picture it looks like you're ½ way up the side of the scale.  (Measuring on a curve sorta changes the rules of what I was used to, if that makes sense... my experience anyway).

Sorry, improper use of lingo.  By tip I meant edge or bevel.  I plan to secure a piece of metal closer to the thickness of the knife blade and put a bevel on it for future sharpening. Thanks for the tip about positioning the Angle Master.

Rick

[RickKrung]

Rick,

Clever use of your Starrett mini square. As an aside, I have a hobby curiosity in measurement and have collected Starrett tools. I still enjoy them, but have stopped collecting.

My original Substitute Target is a flat piece of 1/16" steel. (That's US big box hardware store measurement). I thinned it to 1.25mm (.050") and ground a bevel on one edge. I posted it, including a photo, on the forum. I found the plastic gift cards work well enough and are easier to trim. They are also less expensive than anything Starrett.

Ken

The Starret mini scale came from my father's machine shop.  Also have the inside 90 deg. center head, which I find very useful.

I plan to do the same with a dedicated piece of metal.  I have a lot of metal stock in various sizes, so should be able to find something suitable.

Rick