Machining long lengths with dual x axis - lead screw and belt drive
I'm starting to build a new machine from maker store - c beam xl kit and want to machine long lengths. I was thinking of adding a linear rail with a belt drive to move long lengths quicker in the x axis, hold it at a the centre position of where it needs to be milled and then use the main lead screw to do the finer milling/ movements.
Is something like this possible or just too hard to program? I have the uccnc uc300eth controller and software.
Re: Machining long lengths with dual x axis - lead screw and belt drive
Are you planning to cut aluminum with this? I'm sorry, but IMO, this maker store gives people unrealistic expectations. V-Slot aluminum and plastic wheels are OK for 3d printers. Not for cutting aluminum. Prepare to be very frustrated.
Looking at this C-Beam XL kit, it appears to be a fixed gantry, moving table design.
So you would be making the gantry longer? Just curious, how much?
The UCCNC software is 6 axis software. Yes, you can add another axis. You would need to home both axis at the start of the program, so another limit switch too.
Then for your G-Code, you would need to manually edit the text to move the belt driven axis to the start position of where you want cut. I'm not aware of a CAM software that has this built in, but it may be configurable in some high end CAM software, but I doubt it.
For a moving gantry design, you would need to add two motors and two limit switches, then you would have 4 motors and 4 limit switches, all of which would need to be homed independently to keep the gantry from being skewed. I don't know if UCCNC or your board can handle this number of independent limit switches, and idependent motor homings, even though it could handle the number of axis.
Again, you'd have to manually edit the g-code to move the axis to the start position.
If you had a 30foot long tube that you wanted to cut in someway at the start, middle, and end, and do this over and over quickly, with a moving gantry, this concept might work. But it would be better to add some automatic clamps to hold everything steady when in position, and not rely on the belt. Like in a factory setting that does the same long tubes over and over and needs it done fast.
You could also just manually move it there and tighten the clamps. Or come up with some better work holding and move the long piece under the machine.
Rack and pinion, or rotating ballnut, or very high lead ballscrews with gear reduction to a servo motor can all be appropriate choices for long machines.
So to answer your question, it depends on how many limit switches your board can handle and whether or not it supports independent motor homing on multiple axis if you're going with a moving gantry. I know the older board that I have running mach 3 can not do this, and that is a drawback of the physical break out board.
In general, not knowing much about your design or what you want to accomplish, I think this is a really bad idea, and that your expectations may be unrealistic. Relying on a belt to hold everything steady over a long axis (and this is probably a small 10mm or less belt?) is not going to work well at all. Also, this C-Beam stuff in general is low end, don't expect good results. For better comments, please provide some screenshots of a CAD file.
Re: Machining long lengths with dual x axis - lead screw and belt drive
Hi Ralphie- Not sure what's in your head, a sketch or CAD file would be good. But sounds complex and what do you mean by long? 500mm or 6m? . Registering moves with that sort of machine is not easy if I'm imagining it correctly. Since you have the space to support the "long" length you may as well make a machine that does the full length...Peter
Machining long lengths with dual x axis - lead screw and belt drive
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