I have a 100W CO2 laser with the Ruida RDC6442S-B(EC) controller and M415DRV 2 phase stepper controllers from Lihniyu Studio Labs. I am about to try some rotary work for the first time and will likely either build my own rotary or buy one. I contacted the guy I bought the laser from about using the rotary and with my laser his solution is swap out the Y axis plug in the controller and add the rotary plug. I figured that was crazy since this controller has the outputs for more axis. When disconnecting the Y axis I am worried that while etching the Y axis will drift from vibration and think its best to have the Y axis energized for holding torque and let the X & A axis do their thing.
I read a few similar posts on here where it seem my controller uses the U axis instead of A. Or I can use the Z axis I think since my bed is manually driven with momentary up and down switches so Z is an available option.
Has anyone done this successfully? Any links you can point me to for upgrading?
Will I need a password on my controller to update it or let the machine know I have added an axis?
Does lightburn keep the Y axis energized when the X and Rotary are used?
I imagine any Nema 23 Stepper driver will work and no need to find a matching driver. Also those drivers are Nema 17 anyway.
Most people that have these and rotaries use the Y axes, so the gantry is not powered.
Most of the stock machines have a 4pin plug where you can unplug the Y axes motor and plug in the rotary… much like the original owner advised.
I think you might have an issue with the Z/U axes with a 6442… I understand some people have them working on 6445, but not the 6442… The axes have different purposes and are not like most cnc machines where you can change their operation much…
I’ve had a motor driver, but after hunting around, it didn’t seem to be a functional add on with the Z/U axes… on a 6442
There are lots of discussions about it on this board…
I did a bit ore digging after the post and found that form my model RD controller I am stuck with X&Y axis only for coordinated movement. Also my needs are not big enough to warrant buying the newer controller to use the U axis as a rotary. I may have a simple mechanical workaround and curious if anyone has done this:
My machine does not have the rotary connection socket so I will need to add one. Since I will be doing that I thought about going one step further. My machines X & Y are nema 17 and thus the drivers are also smaller amp drives paired to NEMA 17. So far all the rotaries I have seen are Nema 23 and using a lower amp Nema 17 driver on a Nema 23 does not make sense so I am leaning toward adding a separate NEMA 23 stepper drive to the electronics case. My thought is to run the 5V, Step & Direction wires that come out of the main controller and run them to a n ON/OFF/ON switch with 3 legs. Then run the same 3 wires from the Y Axis and Rotary axis driver into the other 2 sides of the switch. This way I can sort of hijack the step and direction signal and then decide which of the two drivers they go to. Also I am curios if the driver that is not selected since it likely will still have power but not receive any motion commands if that motor (ie the dsiabled Y axis) will still be energized and possibly hold its position wherever it is when I switch over to the Nema 23 driver.
I think what you propose should work… Of course, you’ll have to handle the floating inputs of the unused motor driver… along with what happens when you switch it with a mechanical switch…if you’re an engineer type, then use the KISS principle… There’s enough things to go wrong without complicating things…
Can you confirm that your machine, almost twice the size of mine and much more expensive, has smaller motors I would think it’s gantry must have more mass than mine.
Many just use the same motors and swap the Y cable or have a switch that redirects the Y motor driver to the rotary…
Let me add that having the Y axes energized may turn out to be more trouble than it’s worth… The motors are magnetic field, so it take work to move them (you’re generating power.) You will have to set the Y to the proper place before engaging the rotary.
The torque applied to the Y axes is very minimal, the major torque will be from the X axes at 90 deg, so there is no effect on the Y axes, no matter how fast you run the X axes.
It’s very convenient to be able to push the Y gantry out of the way to move or adjust the rotary… I would not want my Y gantry locked when I run a rotary and I’ve done a lot of mugs,cups and acrylic tubing…
Thanks for the reply. Im 90% sure they are nema 17 and will verify when I am at the hangar where my laser is kept. So it seems like a non issue with the gantry moving when the Y axis is powered down. I will just try the swap out the connector method first. With a rotary likely a Nema 17 is fine so could find one or build one with a Nema 17 so it can use the same driver I already have.
In regards to how lightburn sees the rotary instead of Y axis: Is it just a direct swapping of the wires, or do I need to set up some sort of new configuration so that the rotary does not run too fast.
Here is the rotary I am considering: I could easily make this and make a better version, but for now I am too busy and want to buy one first. Any thoughts on this rotary?
Do you have a rotary you recommend for cups and tumblers?
Thanks for the reply. I saw the Piburn 3 and 4 and if I were to make one I would likely do something similar with the rotary offset so longer items could be done.
sorry for my late reply, I had been sick. Ok so I had a chance to look at my machine and despite being 600 x 900 it does have Nema 17 motors which is nuts. However, I have never had an issue with it and it runs just fine that way. Not a lot of load on a cutting system that does not have drag from the workpiece I guess. Anyhow, is there a rotary people recommend that has a Nema 17 option? I am sure I could make motor plate adapter if needed. Or my idea to have a dedicated 3rd stepper driver for the rotary could work. I just swap the step direction cable from one driver to the other and then I can stay with a Nema 23 if the rotary I buy has that.
The drag on your motors are mostly that of accelerating the mass on that axes. I have a China Blue that was originally 5030 in size, it uses NEMA23, as does my PiBurn.
The D80 rotary that came with my fiber also has a NEMA23 motor on it…
Before I changed a bunch of stuff, I’d see if the NEMA23 can be driven by the setup for a NEMA17… it’s just smaller… There is much less torque required on a rotary than driving the other axes…
It might just work…
On my machine, I noticed the motors got so hot I couldn’t put my finger on them… I check they motor driver and they had them set to twice what the NEMA23 motor current limit… I lowered it to the correct value… they run warm now… had to lower the X acceleration values a little… but I was really applying a lot of acceleration…
You could run another motor driver and a pair of double pole switches to just switch it to the other motor driver… add another 4 pin connector to plug the rotary into…
Does yours have a place to plug in the rotary now?
I would think it’s gantry must have more mass than mine.