i wish you all a healthy new year!
I made the decision to "cnc" my chinese lathe, an Optimum D280x700 (today model TU2807), an "slightly above average quality" 11x27,5inch lathe.
But before starting the build-thread for it, i have to make some detailed decisions, that i want to discuss with you here, if you are willing to help me with this.
I will give numbers, so you don't have to quote for answering only individual questions
1.
As there are already glass-scales mounted, i am planning to buy an AcornSix.
The three encoder-ports should cover the two scales and the spindle-encoder, right?
This SubD-Ports understand RS422, right?
2.
I want to use JMC, Leadshine, Stepperonline or the like AC-Servo-systems. 200W in X, 400W in Z. There is very little room for the ballscrew, and a stronger servo would kill such small ballscrews like i have to use there (seems to become a 1002-ball-screw, still CADding)
TTL step/dir should be fine for such short distances in the cabinet, right? No need for the RS422-Diff-Drive-Output, if my servos can use TTL directly?
Any objections here?
3.
I am not sure if i should go for fixed-encoders for manual control of the axis (via USB-BOB), or if i should buy the wireless-pendant...
The USB-BOB seems to be a NICE gadget, unfortunately it's not that cheap. But I have some MPG-encoders laying around, they wouldn't cost me additional money. And i think i would like the rapid-feed-override, and i would love to use a joystick for rough positioning...
Only drawback, it will have to be fixed because of the size and cables.
The wireless pendant is slightly cheaper, ultra-mobile, but only one axis at a time/one handwheel, no rapid-feed-override there, and i don't know if i have enough free inputs for integrating such a "joystick" without the BOB...
I don't think i can afford both, so i'll have to make a decision here. Any thoughts/hints you can give me regarding this topic?
4.
Does the USB-BOB also have such a miiiinimal delay, like the wireless-pendant? Is it just like with the WMPG, or is the BOB maybe even faster?
Directly connected MPGs (like with the encoder expansion kit) would be slightly more direct/less delay, right? The USB-route will eat some microseconds?
Not that the minimum delay of the WMPG would ever have been annoying me, just asking for technical details here.
5. Is there any way to integrate an analogue-joystick? Just like in RC-controls, Joysticks and so on, with potentiometers.
That would be REALLY nice for rough positioning of a lathe...
I'd be glad, if you would share your thoughts with me here. And because i know you LOVE pics, here are the first three for you:
Best regards,
Marc