Sturges turning system for mills

[cyclestart]

this thing looks sweet:
Turn any CNC mill into a precision CNC lathe with the Sturges Turning Head

Many of us have the poor man's version of the head but the tool holder is interesting. Rotate it and it simply stays in place, no need to lock the spindle. Much tidier than hanging a tool post off the head. Anyone had a chance to try this or have an idea what the holders go for ?

A pic of my (much) cheaper turning head

[lerman]

this thing looks sweet:
Turn any CNC mill into a precision CNC lathe with the Sturges Turning Head

Many of us have the poor man's version of the head but the tool holder is interesting. Rotate it and it simply stays in place, no need to lock the spindle. Much tidier than hanging a tool post off the head. Anyone had a chance to try this or have an idea what the holders go for ?

A pic of my (much) cheaper turning head

Looks good.

I disagree about the holders, though. Instead of that or hanging a tool post off the head, hand multiple tool holders off the head. That gives you gang tooling, and you can use multiple tools without a tool change.

Ken

[ninefinger]

From the looks of it and the lack of mention in the FAQs and elsewhere you can't do threading, plus the indexing is "manual" by 15 degree increments. I take that to mean you lock a pin in after you turn it by hand.

Neat idea but not complete in my books.

Mike

[hoss2006]

The lathe attachment is nothing new, I did mine back in '07 but the tool holders are very cool.
Still, $4700 is a bit of a shock.
Hoss

[cyclestart]

It's the tool holder that's interesting.
Judging by the video it should be possible to build one that uses a threading insert ??

[ninefinger]

It's the tool holder that's interesting.
Judging by the video it should be possible to build one that uses a threading insert ??

You could make a holder that holds a threading insert - but by their definition the spindle is not locked so that it can pivot about the cutting point.

A threading insert needs to maintain the proper angle to make a good thread, if it pivots you might end up with a thread with a 60 included angle but one side will be lets say 25 degrees and the other 35 degrees. So you need to lock the spindle - defeating the whole idea behind their custom tool holder.

Mike

[hoss2006]

It's the tool holder that's interesting.
Judging by the video it should be possible to build one that uses a threading insert ??

Yeah and TTS versions that could be used with an ATC might be worth contemplating, hmmm.
I'd lock the spindle though.
Hoss

[steamboatmodel]

When I was working we used the cnc mill as a lathe a number of times, chucked the material in the spindle and mounted the tools on the bead on angle plates. Never got a chance to film it though. With the one showen I would definatly have the spindle locked.
Regards,
Gerald.

[bogiestl]

I've been using a Hardinge indexer (and occasionally a Hardinge lathe...).

If the thing doesn't have the torque for CNC milling, then it's only "sort of" useful. If they could set it up to also operate like a rotary table (transmission?), that could be interesting.

I've also done vertical CNC lathe work, chucking the tools into the vise, and swinging the part...

What goes into the "homemade" type? I figure I could mount a tool off the side of a head...

[wizard]

Actually worth a patent as I've not seen anything like them. It would be very nice to see the tool holders marketed separately.

As to the spindle, it is a nice start but a bit pricy. Then again it looks like they put some sound engineering and quality into it. The little detail about the drive accepting either 120 or 240 volts in shows they where thinking. On the other hand it would have been nice to see a servo option that allows for fourth axis use.

[cyclestart]

In response to a PM (better late than never edition)

The ingredients of my little turning head:
7x mini lathe headstock assembly
mini lathe motor pulley and belt
mini mill motor and control
4" 4 jaw chuck w/adapter plate for mini lathe
all parts from the good people @ littlemachineshop

It wasn't a planned thing, more a result of ass dragging on a small lathe project. Future mods may include a small disk brake with integral encoder disk for manual indexing and thread cutting, (waiting for the right dumpster find )

[bogiestl]

Do you think it might be possible to take that basic setup, and do a two-motor version, set up so that you could run a "plain" motor for turning, and a stepper or servo for using it as a vertical fourth axis? Is the minilathe spindle rigid enough to allow that sort of thing?