Questions: 3 additional rotational axis



  • Hi there,

    In my current setup I have a delta printer with two extruders and a duet 2. I would like to add a tilting and rotating bed. This would require 2 more steppers and 2 more end stops. Also I would like to add an additional stepper for a tool changing mechanism. From a hardware standpoint this should be doable. I could definitely get a duex5 which would solve all those problems.

    Q1) I'm not sure If I could make the project work with using existing external steppers and the expansion port. I'm not sure If I could connect the additional 3 required end stops.

    But I'm struggling a bit more with how the configuration side would look like and how I would actually control the steppers. All the steppers would control a rotating axis

    Q2) I would like to set the values for the rotational axis in ° (e.g. 125°) is that possible? Or do I have to to adjust the M92 command for setting the axis steps per unit so that for example a full rotation of the bed equals 360mm?

    Let's assume I've got the axis set up (independent of in ° or in mm).

    Q4) How would I control an axis? For example if I wanted to turn the bed to 50 units and the bed stepper is mapped to axis U >> G1 U50 ?

    Q5) The next question then arises for me. Can I control the speed of that axis independently? For example if I wanted to move the effector to Z50 at 1000mm/min and rotate the bed to 50units at 400 mm/unit G1 Z50 F1000 U50 F400?

    I think that sums up my current batch of questions

    Greetings
    Daniel



  • @schpongo said in Questions: 3 additional rotational axis:

    Q2) I would like to set the values for the rotational axis in ° (e.g. 125°) is that possible? Or do I have to to adjust the M92 command for setting the axis steps per unit so that for example a full rotation of the bed equals 360mm?

    the firmware is unitless, as such it is up to you and the CAM package (or slicer) to set the bar for what unit the axis is; and configure the firmware so the number of steps equals 1 of whatever unit is desired, be it millimeters, degrees or furlongs.

    Q4) How would I control an axis? For example if I wanted to turn the bed to 50 units and the bed stepper is mapped to axis U >> G1 U50 ?

    yes, you can choose between absolute or relative moves (G90, G91), but all the moves are done with G0/G1 U50 (where 50 could be go to position 50, or advance by 50 units depending on absolute or relative moves)

    Q5) The next question then arises for me. Can I control the speed of that axis independently? For example if I wanted to move the effector to Z50 at 1000mm/min and rotate the bed to 50units at 400 mm/unit G1 Z50 F1000 U50 F400?

    you cant control the speeds independently, they're always coordinated. so if you need to move Z by 50mm and U by 50 units they will always have to move at the same speed to reach their target position at the same time. (but if you move Z by 50mm and U by 20 you get the desired speed differential ofc when running it at F1000)



  • @bearer

    Sorry for the late reply, but your answer was very helpful.
    Thanks!

    Greetings
    Daniel Kurth


Log in to reply