Welcome! Log In Create A New Profile

Advanced

[SOLVED] Lead screw synchronisation problem

Posted by isolt 
[SOLVED] Lead screw synchronisation problem
June 26, 2013 06:11AM
I've assembled a Mendel90 but am using a RAMPS 1.4 and the standard fork of Marlin.
NEMA17 78 Oz-in CNC stepper motor stepping motor/1.8A on the lead screws - Model Number:17HS8401
I've wired them in series as in the assembly instructions (2 wires from the board go to one motor, 2 to the other then they're connected together)

In pronterface I can home the z axis as well as move it up and down as much as I like. If the motors are off I can easily turn the lead screws with my fingers.
When I try and centre them with "G1X0Y0Z100F30000" the left hand leadscrew drives down but the right sticks and the motor makes a grating noise (I can see that the motor drive shaft is not turning, it is not just that the coupler is slipping).
I have an lcd controller hooked that I can control the axies with. If I use the LCD to move the Z axis I get the same jamming problem, but it seems to alternate from one leadscrew to the other.

Any ideas?
I'm stumped... I tried turning up the pot on the Z stepper driver but no change. The Z stepper driver isn't hot to the touch either.

Edited 1 time(s). Last edit at 06/27/2013 04:29PM by isolt.
Re: Lead screw synchronisation problem
June 26, 2013 06:27AM
Looks like the max Z speed is set too high in the firmware.


[www.hydraraptor.blogspot.com]
Re: Lead screw synchronisation problem
June 27, 2013 04:28PM
Thanks! That was exactly the problem. I had my max Z speed set to 5 rather than 4 like in the Mendel90 fork.
Apparently trying to turn those z screws at 300RPM was asking too much.

Cheers
Sorry, only registered users may post in this forum.

Click here to login