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.
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.
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.
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
as-is.
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!
