cnc guys start drooling

[tom osselton]

My son just showed me this video..... Just amazing!

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[Arbalist]

I'd really like to see the cutter shape and slow motion to fully appreciate the process! 

[Tony_J]

I'd really like to see the cutter shape and slow motion to fully appreciate the process! 

I want one

[DMIOM]

I'd really like to see the cutter shape and slow motion to fully appreciate the process! 

Well, as a start, have a look at this - is it slow enough?

Then, maybe replace the mechanical master templates with electro-wizardry.

What I did find very interesting was the brief system sketch at the beginning of the original video which appeared to show a cardan shaft betwixt the headstock spindle and the back of the carriage.   I wondered if it could be simplified as effectively a copy lathe or even just a TTA but with a master profile which rotated in exact 1:1 with the workpiece, and then a follower which guided the tool (secondary power spindle?) in & out following the master?

There's probably a patent from the 1800s which has the progenitor for this, just driven from a line shaft!

Dave

[AdeV]

Good grief, that's quite a clever piece of kit...

What I did find very interesting was the brief system sketch at the beginning of the original video which appeared to show a cardan shaft betwixt the headstock spindle and the back of the carriage.   

I think that's just the power drive to the active tooling, isn't it?

[philf]

I'd really like to see the cutter shape and slow motion to fully appreciate the process! 

[Lykle]

Wow

After I saw the first video I thought that they were somehow modifying the cutting bit depth during every rotation.
But now I see that maybe it just moves so fast that in combination with the rotation of the part is produces a flat surface.
So combining the two rotational speeds allows you to change the surface curvature. Clever. At least for the last video.

The other stuff, I must be using a movable cutter, how else can you cut a groove in a cylinder with almost straight sides?

But that gear! That will take some wrapping of brains around.

[NeoTech]

I think that's just the power drive to the active tooling, isn't it?

Been standing up close to a mechanical (not cnc) machine like these on a local machine shop.. The power tooling part is syncronized with the spindle at a gear ratio for most parts. with a shaft that drivs the tooling at an offset.. its basicly a spirograf.

The cnc versions have obvious benefits though.. deargod i want one.

[NeoTech]

after some solidworkd simulation both tool and part is spinning in the same direction. part is spinning in 1:1 and tool is spinning in 2:1 if tool has 3 cutting surfaces if it has one surface it would be spinning 6:1 to generate the hexagonal shape.. angle of cut requires some tinkering with the ratios but that gear can be produced with similar math.. or just use the gcode for it if the machine has a powered spindle in the gang tooling setup.

[philf]

The 'flat' faces produced aren't in fact flat but sections of an ellipse. The bigger the ratio of cutter to workpiece diameters, the nearer you get to a flat.

Unless I ever get many hundreds of hexes to produce I'll stick with my dividing head or a Stevensons Hex ER32 block.

Phil.