Problem with my Z axis

eddymcfly

Today I noticed that my Z axis is not functioning correctly. I connected my printer to Simplify 3D heated the extruder and then tried to raise the extruded on the z axis, but it would not move. The motors are spinning and so are the rods, yet for some reason the extruded wont raise on the z axis. I then decided to home the printer and everything seems to be functioning, the printer moves on all axis and even raises and lowers on the z axis in order to home itself. However every time I attempt to raise the z axis using the jog commands on simplify 3D i still have the same issue. Does anyone know what the problem might be? Please and thank you. 

Samuel Pinches

I don't understand ... the z motor is spinning, the couplers are spinning, the rods are spinning, but the gantry isn't lifting? 

Laser8302

Check your step size you are commanding on the z-axis would be my first though. If you are only moving it 0.01mm you won't see much movement. You say it moves up and down when you send the HOME command? Are you able to use the LCD to move the gantry up and down?

eddymcfly

Correct everything spins but the gantry wont lift. I am also able to use the LCD to move the gantry, and I even went as far as running a test print and everything worked as normal. I then tried to raise the gantry up again using the jog controls on simplify 3D, but I was still having the same issue. The rods and motors would sping but the gentry would not lift, I just don’t understand it. 

cs2000

Theirs literally no way that can happen. The lead screws go through a brass bushing on either side of the gantry with a thread in them. If you’ve verified the gantry does go up and down it means they’re meshing ok and the threads haven’t been ruined , any program that spins the steppers will raise and lower the gantry. A motor spinning is a motor spinning, doesn’t matter what told it to spin, the action is the same

Samuel Pinches

I think we're going to need a video to understand the issue...

eddymcfly

Hey guys I know its been a while since I posted on this issue. But I was out of the country and now I’m back and still having the same issue except now I cant even properly level the bed. So the rods only spin and the arm moves when I apply a 0.1 adjustment on the +Z axis. Anything above that like a 100 adjustment and I only hear the motors try to work but no movement, the -z axis works fine. Anyways i ended up leaving this alone because in the end my prints would still come out fine, however I was trying to print something yesterday and noticed that my extruder was sitting higher than normal. So I decided to level the bed using the bed leveling option on the touchpad. However, every time i hit home or try to print the extruder would still settle way to high. I have tried to level the bed multiple times and also resetting the firmware. I don’t even know what cause the issue. One minute it was level and then on the next print it just started resting higher than usual. 

Laser8302

Sounds like you might need to lube your rails and screws. Get this lube here would be my suggestion.
Also check your Z-endstop block in the right-hand tower. It might be set too high to level the bed properly. You can adjust it down if needed.
One final check would be to make sure your gantry is level. Take a set of calipers to the top edge of the gantry to the top edge of the frame. (Run the Z-axis to ~280mm above the bed for this.) Us the front edge where they rolled the steel over giving you a nice flat surface to measure to.

I found the max speed should be 15mm/s on the Z-axis. If you are running the community firmware, I think this might be set to 25mm/s, try this: (With the gantry near the bed.)

G0 Z150 F600 ;Move gantry up 150mm at 10mm/s
Should be no noise, now send this:
G0 Z10 F15000 ;Move gantry down 140mm at max speed defined in firmware

First move should be no noise other than the usual stepper motor noise. Second move, if your firmware max speed is wrong, will be noisy and the axis probably won't end up a Z=10.

eddymcfly

Thanks for the help, I will definitely give this a try. I also thought about adjusting the Z-endstop block, but I found it odd that it was working fine on the previous print. Which led me to believe that this might be a software issue. 

Laser8302

Try hooking up to your printer with Pronterface and type M851 Z0 then G28. This will reset the Z-offset to 0 and home your printer. Then check your bed. If it fixes your problem, double check your slicer settings for an M851 somewhere.

eddymcfly

okay so I got the lube you mentioned, lubed up my rails, leveled my gantry, reset the z-offset, and now everything thing works properly. Thank you so much for the help! 

Samuel Pinches

@eddymcfly Beautiful! Happy printing!