I started turning some Safari leg chairs with my 40" woodworking lathe and was disappointed with my lack of skill keeping the legs symmetrical. As I was think about how to make repeatable turnings, I thought of adding a cnc above the lathe and only using an x and z axis to make the cuts.
As I started researching it, I see people like Izzy Swan have made a manual version with a router and a frame, and others who have a lot of experience with custom cncs have built full cnc lathes; but I’m just looking to upgrade an existing lathe and that market doesn’t seem to exist.
If I built a box around the turning part of the lathe with a groove/track above the center-line that would only allow the router to move in-line with the turning.
Could I mount the two motors from an original Maslow at the end of the box and use the chaining for the x-axis and use the built-in z axis?
Or could I mount the cable ends of the new maslow at the end or each box and only use the x-axis and built in z -axis?
Any other ideas.
I can’t find the site that gave me th einspiration for this, but here are some other examples.
the maslow parts are probably a bad place to start from, they aren’t drivable by
most common CNC firmware, so you would have to take on a significant programming
task before you could start making chips.
The place I would start is from figuring out how to generate gcode for the machine. That’s going to be the hardest part I think and if you can figure that out the rest should be pretty straight forward
Would it make sense to use a classic cnc setup with a standard XYZ similar to using a laser with a rotary attachment? Instead of the rotary, use the lathe as the y axis.
I want the lathe to spin and have the cnc just go left-and-right and up-and-down.
You could do it with Maslow, but unless you want to make the whole thing really big (like a 10’ lathe) you are probably better off using a leadscrew type setup. No matter how you go about it, it’s going to require a big of work to take any off the shelf parts and make them work that way.
Sounds like you need a z axis and a linear rail x axis. You need the gcode to be made from the cross section of the one edge of the spinning part… Interesting problem to think through. It would basically be a carve operation in estlecam over a 3d surface but only as one line.
Fusion will let me generate the G-code for:
- an x the length of my turning,
- a y as wide as my bit, and
- a normal z for the depth.
I was hoping that you could set the Maslow workspace to be as wide as the bit and calibrate one axis for the length of the turning.
You can absolutely do this, it just isn’t the normal use case so it would require a bit of hacking.
I’d look into a lathe duplicator rather than (gasp) trying to make it a CNC project, repeatable turnings are kind of their thing. I’m guessing the fluting isn’t your issue, since that’s pretty easy with indexing, and I think most powermatics came with one built-in
I have a BobsCNC Revolution, with a pass through kit that will allow flipping parts end for end to get around 2 feet on each end, but that seems like overkill for what you’re trying to do. Plus it’s a little short. There are DIY plans for Phil’s Rotary Demon (I’d use a different controller, theirs is rather overpriced) that you can make larger, but overkill still applies.
I wonder about using templates cut on Maslow to guide a tool?
no, a carve operation assumes that you can rotate the spindle in both
directions. (think a rotary axis on a laser cutter or regular CNC mill that
just swaps the Z motor to rotate the piece instead)
a CNC lathe is a very different beast, the spindle is spinning at a high speed
and for most operations (i.e. anything but threading) you don’t try to time your
cutter movement to the rotation.
trying to use the maslow hardware/firmware for this would be a problem becasue
the maslow firmware doesn’t let you define X to be one motor and Y another, X
and Y are tied together in the chain triangle calculations
That’s why I was saying the the maslow hardware is a bad fit for this use case
Funnily enough, it took three hours of research before the term lathe duplicator came up. Now that I know it exists, I totally agree that this will be a much easier solution unless you were producing a lot of intricate designs.
The rotary demon is exactly what I was envisioning, but with my lathe instead and in a box for dust control. Thanks!