A small useful 3D printed tool

[aquataur]

Hihi, I learned a new word: 'gewgaws'.

I typically remember the useless, but funny words...

I tested the SE-77 settings in your calculator and it worked. 

Thanks for checking this out. I suspected it may work.

@Perra, thanks for this clarification.

I just realize that my quest was condemned to fail right from the start, since the setting of T-USB to achieve a certain angle hinges on a stable projection distance - i.e. a jig that "locks" the knife´s edge to the USB.

How daft. I have created a lot of commotion for nothing.

[Perra]

I'm pretty sure you can.  I learned it from jvh in this thread that the formula is a bit "generic" (for lack of a better word?). It will calculate the USB height, as long as you can figure out the Jig Diameter, and Projection Distance adjustments.

Thanks cbw..
You are right, as always. Just haven't thought of the possibility myself. 

[aquataur]

Perra,

I just stumbled over a thing...

All T-USB calculation hinges on the fact that the projection line goes (ideally) exactly through the center of the (knife-) jig.

With the T-Cube, the real projection line is offset of the ideal projection line by 1mm up, which is comprised by the thickness of the ruler blade.

I have addressed the offset error above (although we were speaking of amounts 10x higher), and it goes back to Dutchman´s printed manuals.

You were trying to compensate for the offset by introducing the 6mm ridge which adds to the USB, but in combination with the ruler this effects to 7mm.

You could make the ridge smaller by a millimeter, resulting in a total offset of 5+1 mm, but that would not cure the problem down where the ruler meets the stone.

I don´t know how large the error will be in degrees, but there is an error. The digital unit will be insensitive to that, but the anglemaster will show false values. All measurements thereof have to be referred to the exact point where the edge meets the stone and not 1mm higher. You could however grind a sharp edge on the ruler...

Let me know if I am wrong. This may well be.

[ArtOfSharp]

With the T-Cube, the real projection line is offset of the ideal projection line by 1mm up, which is comprised by the thickness of the ruler blade.

The measurement on the top of the ruler is at the same distance as on the bottom of the ruler, so when the USB is raised to the point that the ruler can freely pass, the measurement does not actually have a 1mm offset.

Another way to think about it: imagine you could make the measurement and flip the ruler over, is it not the same distance?

[aquataur]

The measurement on the top of the ruler is at the same distance as on the bottom of the ruler

This is certainly true for an angle cube, or whatever those digital units may call themselves, but not for the angle master. The error may be small, but this whole issue is about improving precision.

[cbwx34]

...
The error may be small, but this whole issue is about improving precision.

For me, the issue is about improving consistency, not necessarily precision.  (If you're using the AngleMaster, precision is probably not a main point anyway.)  Using a flat ruler is arguably more accurate than setting the AngleMaster on the side of a knife with a taper, but it is also more consistent.

When calculators "arrived", too much emphasis was placed on accuracy... most of which was later proven unnecessary.  While I don't know the exact error (if any) in using the T-cube as pictured, a simple test should give you an idea... just set the USB using a calculator, then check it with AngleMaster.  I think you'll find it pretty close, (not degrees) and if all you ever used was the T-cube and AngleMaster... consistent.

I think any method that is decently accurate, say +- a degree, consistent, and repeatable, will give most users the desired result.

[ArtOfSharp]

I have a question about using the T-cube...

In this photo the T-Cube seems to be under/behind the USB (on the same side as the person when looking at the main wheen on the left side of the Tormek) when measuring to the wheel.
https://forum.tormek.com/index.php?action=dlattach;attach=6136

Is this the method for measuring when using the Angle Calculator software?

Or should the T-cube be placed on top of the USB (on the jig side as would be used when sharpening)?

The reason i ask is that the measurements are different from other calculators.

For example, a jig length of 128, and angle of 10 degrees, in the Angle Calculator i get 62.64.
You cannot view this attachment.

But in another calculator the measurement is 61.43.
You cannot view this attachment.

[cbwx34]

I have a question about using the T-cube...

In this photo the T-Cube seems to be under/behind the USB (on the same side as the person when looking at the main wheen on the left side of the Tormek) when measuring to the wheel.
https://forum.tormek.com/index.php?action=dlattach;attach=6136

Is this the method for measuring when using the Angle Calculator software?

Or should the T-cube be placed on top of the USB (on the jig side as would be used when sharpening)?

The reason i ask is that the measurements are different from other calculators.

...

The side doesn't matter.  I believe that's actually a difference in calculators.  The 2nd calculator is Dutchman's?  And I think it was created before the "fix".  If you look at the line above the chart (if it's the same one), I see this...

 You cannot view this attachment.
(Replaced picture with a better one)

... that says USB center to Stone.  (The original calculator made this and some other assumptions that the "fix" fixed.) 

[aquataur]

For me, the issue is about improving consistency, not necessarily precision.  (If you're using the AngleMaster, precision is probably not a main point anyway.)  Using a flat ruler is arguably more accurate than setting the AngleMaster on the side of a knife...

I agree. With the AM the result will be better using the ruler, with a digital cube the offset is not relevant.

[Perra]

I think the question already been answered.