Did anyone else experience the 4th axis on the YOOCNC/carving-cnc 6040 to be very weak?
The stepper is much smaller then on the other 3 axis, wich is fine (given it's limited travel distance and thus required speeds).
But it is hardly geared down at all by this tiny belt.
Even the slightest mechanical resistance between cutter and part sends the axis spinning backwards instead of holding it's position.
Did any of you replace this axis or it's stepper?
What could be a good choice?
What settings do you have in MACH3 for this axis? (Maybe my settings are wrong. I had to change it a lot to make it do 360=360° instead of 360=multiple comlete turns.)
I bought one, but haven't used it yet - still coming to terms with using a flat bed.
I am concerned about the lack of holding power - I must say I haven't really thought of a use for it yet - most of what I've seen appears to be rather naff decorative carvings (in my opinion at least!) although I do have the idea of using it to make light fitting bases from some kind of plastic, but if it can't be milled at a respectable rate without deflecting, the whole process could get a bit boring.
Question is: gearbox or stronger stepper motor.
What size of stepper can the line driver card handle?
I asked carving-cnc for the settings to use in MACH3 (they supplied only settings fox X,Y,Z but not A).
RusselK: Did you get any settings to enter for the A axis into MACH3?
What values are others using?(steps per degree, velocity, acceleration, step pulse, dir pulse, ...)
obviously the XYZ-values cannot just be copied since moving the A-axis by 360 must be 1 full turn.
Last edited by MarcusWolschon; 05-06-2013 at 01:48 PM.
I hooked up my 4th axis today just to see what Marcus was on about - I have to agree, it has bugger-all holding power. While I haven't actually tried using it to mill anything, I can't imagine it being of much use for anything but balsa wood or foam.
Also, those velocity and acceleration figures seem ridiculously slow.
I think if I am ever to use it, I'll need to replace the stepper with a bigger one, and perhaps replace the driver board, as it's much smaller than the ones for the other 3 axes, and maybe consider changing the pulleys to increase the mechanical advantage.
I'm having a hard time finding a planetary gearbox for that small NEMA23 stepper.
They are also too long (stepper is 41mm deep, at >=63mm it would collide with larger mounted parts)
Any idea what else to do?
And a larger stepper would probably require a new driver card.
How much of a stepper can the driver card handle?
Maybe we could do something to replace the belt?
2 gears milled out of aluminum stock will probably not gear down enough.
It's not thick enough to add holes for 2x 608 ball bearing supporting an additional axis, so we can use 4 gears.
Maybe an L shaped motor holder and a worm-drive could work.
Would replacing the 24V with a 48V power supply change torque?
(I already gave that water pump it's own power supply as it's electrically extremely noisy and is the cause of lost steps.)
Can I just replace the 1.8A NEMA 23 with any 3A 3Nm(425 oz inch) high torque ones?
The driver card seems to be identical to the other axis that use 3A steppers.
Do I have to be careful about any other values of the stepper?
Since its longer I plan to test it mounted like the current one but finally mount it from the other side using 4 spacers (to new research have stepper body and part collide).