Feature suggestion: Kellering function

[MidniteMachinist]

I'm sure I'm far from the only one who watched Stefan Gotteswinter on YT. I just finished watching his latest video, which all about cutting radii on a manual mill using the DRO, using a technique called Kellering. I think this could be a super useful addition to the TouchDRO toolbox, sometime in the future.

I know that one can use the bolt hole circle function for this, which he does show... It's particularly useful for cutting curved slots, where the tool centerline is coincident with the centerline of the arc.

However, I think the radius milling function he demonstrates is more suited to external radii, than the bolt hole circle function. Because the tool centerline is no longer coincident with the centerline of the arc, the bolt hole circle method requires you to account for the radius of the tool. The dedicated radius function accounts for this inherently, which mitigates one possible avenue of error. Second, it provides the ability to machine a radius in the XZ plane using a ball endmill, whereas the bolt hole circle function only works in XY.

That second ability is what prompted me to suggest this here. That, and It could also be useful in the lathe configuration, for radius/ball turning using a round-nosed tool.

Further, it could also have an "slope function", to be able to cut angled straight surfaces... In XY with a standard endmill, or in XZ with a ball endmill (or XZ on a lathe, with a round-nosed tool)

Anyway, saw the video, and was inspired to post.

 

[twhite]

Used that process many times years back. I have a book on radii and one someplace on angles.
Use the formula and create any size you want.

Cutting oil is my blood.

 

[RJSakowski]

My Grizzly DRO has an arc function that lets you cut an arc in the xz, xz, or yz plane. The function calculates points on the arc and enters them in as subdatum coordinates. When you enter the next point on the arc, it displays how far you have to go to that point. You are essentially cutting the arc in steps. The quality of the cut is determined by the number of points you select. The more points, the finer the steps. However, more points adds to the tedium of the process and increases the possibility of error. The arc is finished by hand sanding or filing.

 

[ycroosh]

I haven't watched that particular video (yet).
That said, I use bolt hole function for this all the time.
Hole Circle and Hole Grid functions have "advanced" mode (long-press the button) that brings up these dialogs:

You can change the projection plane to do vertical radii.
To account for the tool radius, you can type "1.75+.365/2" into the "Circle Radius" field, and the sub-datum coordinates will be at the right places.

Hope this makes sense
Yuriy

 

[MidniteMachinist]

Huh. Neat! Didn't know those dialogs existed. That's on me... Guess I should RTFM.

As for the math... I'm assuming that's an example? Am I correct in thinking that for a desired radius (rD) using a tool with a diameter of (T), the formula would be rD=rD+(T/2) for a convex radius, and rD=rD-(T/2) for a concave radius?

ETA: It also looks like I wouldn't have to account for the radius if I'm using radius compensation with the tool library, correct? At least, in the XY plane.

 

[Ischgl99]

I watched his video yesterday too, before I realized my DRO could do this, a few weeks ago I wrote an Excel spreadsheet to do the calculations in a table for a cove I wanted to machine. Much simpler to have the DRO do it for you. It was nice seeing other ways of using the DRO for arcs, I never even thought of using it for an arced slot. Curiosity question, would it make a difference doing it Stefan's way by leaving the cutter in the work while moving it, or using the quill to down feed into the curve at each step? I'm thinking having the cutter clear of the work while positioning could minimize cutting too deep if you overshoot the numbers while changing positions.

 

[ycroosh]

I'm sure I'm far from the only one who watched Stefan Gotteswinter on YT. I just finished watching his latest video, which all about cutting radii on a manual mill using the DRO, using a technique called Kellering. I think this could be a super useful addition to the TouchDRO toolbox, sometime in the future.

I know that one can use the bolt hole circle function for this, which he does show... It's particularly useful for cutting curved slots, where the tool centerline is coincident with the centerline of the arc.

However, I think the radius milling function he demonstrates is more suited to external radii, than the bolt hole circle function. Because the tool centerline is no longer coincident with the centerline of the arc, the bolt hole circle method requires you to account for the radius of the tool. The dedicated radius function accounts for this inherently, which mitigates one possible avenue of error. Second, it provides the ability to machine a radius in the XZ plane using a ball endmill, whereas the bolt hole circle function only works in XY.

That second ability is what prompted me to suggest this here. That, and It could also be useful in the lathe configuration, for radius/ball turning using a round-nosed tool.

Further, it could also have an "slope function", to be able to cut angled straight surfaces... In XY with a standard endmill, or in XZ with a ball endmill (or XZ on a lathe, with a round-nosed tool)

Anyway, saw the video, and was inspired to post.

How does this look:

On a related note, I'm probably going to redo all sub-datum dialogs to always show the projection plane and center/starting position. I have a sneaky suspicion that most people don't know that majority of buttons in TouchDRO have secondary (and often ternary) functions...

Regards
Yuriy

 

[ChazzC]

I have a sneaky suspicion that most people don't know that majority of buttons in TouchDRO have secondary (and often ternary) functions...

Regards
Yuriy

First off, I’m not questioning you, just need clarification: ternary or tertiary? I could see either, but I know how “reliable” auto-complete & auto-correction can be.

 

[ycroosh]

First off, I’m not questioning you, just need clarification: ternary or tertiary? I could see either, but I know how “reliable” auto-complete & auto-correction can be.

Tertiary
Hey, English is my 5th language, and the only language I learned as an adult, so the brain wiring is not perfect (my coworkers recognize my code by presence of "Yuriysms", like "Lable", "avaliable". etc.).
Plus, in my defense, I was just reading about parsing "ternary" operators in a compiler...

 

[MidniteMachinist]

Holy crap, Yuriy, that's awesome! Super intuitive.

On another note, I'm gonna go long-press all the buttons now.