I wrote to Ruida expressing the interest and need for a dedicated rotary axis on the RDC6445G . According to the the work and effort the good folks at LightBurn have put into exploring the possibility, I remember reading that their conclusion was that the firmware does not allow for control of the U axis for a rotary. Commands to move this axis cannot be combined with commands to pulse the laser.
Today I received the following from Cyan Liang Overseas sales manager, Shenzhen Ruida Science Technology Limited:
“Thank you for your email.
RDC6445G has rotary fundtion,but it is the apecila firmware,if you have to inofrom me you need this firmware bedore you place the order.