Z-Axis loosing steps?

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Legion 2.3
Posts: 84
Joined: Sun Apr 20, 2014 6:23 pm

Z-Axis loosing steps?

Post by Legion 2.3 »

Hello guys

I´ve been printing for a few days now with my Felix 3.0 DIY-kit.
I noticed that i got vertical stripes all over my prints. First, i thought it could be a bad filament, but the objects are too tall! That means, 32 mm in CAD but 33,2 mm at the print! The x - and y - dimensions are correct, but Z is definitely wrong !

Could it be that the Z-axis-stepper-motor is loosing steps?
If that´s true, what can I do to fix that?
More power for the motor?

I use Slic3r at the moment, but the same happens with Sfact.
Attachments
20140507_222711.jpg
20140507_222647.jpg

Saamec
Posts: 157
Joined: Fri Jun 21, 2013 9:28 am

Post by Saamec »

Mechanics broken down, drag out all the screws, make sure that there is no backlash. However console design is not able to completely get rid of such lines.

Legion 2.3
Posts: 84
Joined: Sun Apr 20, 2014 6:23 pm

Post by Legion 2.3 »

Are you sure that it has to be the mechanics? I can't believe that that the screws can become loose after 1 print. I had this problem from the beginning.
Should I disassemble the entire printer?

Legion 2.3
Posts: 84
Joined: Sun Apr 20, 2014 6:23 pm

Post by Legion 2.3 »

Maybe you´re right, i discovered that the spindle wasn´t mounted correctly on the stepper because the M3-thread of the spindle was crossthreaded. I´ve recut the thread and mounted everything back.

While removing the spindle from the motor, the Z-axis jumped up and i got 2 small bumps on the kapton tape :oops:

The other screws also lost much tension.

However, I´ll try my next print tomorrow, i hope it´s better now.

Legion 2.3
Posts: 84
Joined: Sun Apr 20, 2014 6:23 pm

Post by Legion 2.3 »

It was still the same after i double-checked all the screws, still bad quality.


Than, I tried to increase the power for the Z-axis (turning the pot counter-clockwise ). Before, i was able to stop the moving spindle with a small force. Now, it has more power, and it looks like it really worked.

The next print was absolutely clean, no gaps or lines, almost perfect.

Does anybody know what is the temperature-limit of the steppers? My motors were about 35°C after 1 h printing.

Saamec
Posts: 157
Joined: Fri Jun 21, 2013 9:28 am

Post by Saamec »

35 degrees is perfect!!!

seaton
Posts: 291
Joined: Tue May 14, 2013 9:04 am
Location: Bunbury, Western Australia
Contact:

Post by seaton »

You could have a problem with you're belts.

Try printing at a different location on your bed and see if there is any difference. I had a problem similar and quite by chance i ran a calibration print in a different location and found it was printing ok. It was the belts had stretched or worn at the place I was doing most of my printing. Once replaced it was back to normal.
Stephen...

Felix 2.0 -> Felix 3.0 dual
Simplify3D Slicer, Kisslicer
Have you added your Felix to the Map? http://goo.gl/maps/HajnZ

http://blog.strobotics.com.au

Legion 2.3
Posts: 84
Joined: Sun Apr 20, 2014 6:23 pm

Post by Legion 2.3 »

It´s getting better but i´ts still not perfect.
As you see at the image, there is still 1 line.

I did everything i could (more power to Z, more tension for the extruder, all screws checked).

That´s just so annoying because it weakens the part at this spot, so it breaks faster.

I got less then 20 printing hours (almost new), so i don´t think that the belts are already worn, and I can´t imagine how the x- and y-belts should affect the Z-axis.

Is that printing-quality normal? Do i just have to deal with it? Can you upload some of your printing results?

Could it be the slicer? I use Slic3r with these settings:

Code: Select all

# generated by Slic3r 1.0.0RC3 on Sat May 10 14:50:48 2014
avoid_crossing_perimeters = 0
bed_size = 255,205
bed_temperature = 55
bottom_solid_layers = 3
bridge_acceleration = 0
bridge_fan_speed = 100
bridge_flow_ratio = 1
bridge_speed = 50
brim_width = 0
complete_objects = 0
cooling = 1
default_acceleration = 300
disable_fan_first_layers = 1
duplicate = 1
duplicate_distance = 6
duplicate_grid = 1,1
end_gcode = M104 S0 ; turn off temperature\nG28 X0  ; home X axis\nM84     ; disable motors
external_perimeter_speed = 60%
external_perimeters_first = 0
extra_perimeters = 1
extruder_clearance_height = 20
extruder_clearance_radius = 20
extruder_offset = 0x0
extrusion_axis = E
extrusion_multiplier = 1.0
extrusion_width = 0
fan_always_on = 0
fan_below_layer_time = 60
filament_diameter = 1.75
fill_angle = 45
fill_density = 0.25
fill_pattern = honeycomb
first_layer_acceleration = 0
first_layer_bed_temperature = 55
first_layer_extrusion_width = 200%
first_layer_height = 0.2
first_layer_speed = 60%
first_layer_temperature = 200
g0 = 0
gap_fill_speed = 40
gcode_arcs = 0
gcode_comments = 0
gcode_flavor = reprap
infill_acceleration = 0
infill_every_layers = 1
infill_extruder = 1
infill_extrusion_width = 0
infill_first = 0
infill_only_where_needed = 0
infill_speed = 70
layer_gcode = 
layer_height = 0.2
max_fan_speed = 100
min_fan_speed = 35
min_print_speed = 10
min_skirt_length = 0
notes = 
nozzle_diameter = 0.35
only_retract_when_crossing_perimeters = 1
ooze_prevention = 0
output_filename_format = [input_filename_base].gcode
overhangs = 1
perimeter_acceleration = 50
perimeter_extruder = 1
perimeter_extrusion_width = 0
perimeter_speed = 60
perimeters = 4
post_process = 
print_center = 127.5,102.5
raft_layers = 0
randomize_start = 0
resolution = 0
retract_before_travel = 2
retract_layer_change = 1
retract_length = 1
retract_length_toolchange = 10
retract_lift = 0.15
retract_restart_extra = 0
retract_restart_extra_toolchange = 0
retract_speed = 30
rotate = 0
scale = 1
skirt_distance = 6
skirt_height = 1
skirts = 1
slowdown_below_layer_time = 30
small_perimeter_speed = 30
solid_fill_pattern = rectilinear
solid_infill_below_area = 70
solid_infill_every_layers = 0
solid_infill_extrusion_width = 0
solid_infill_speed = 70
spiral_vase = 0
standby_temperature_delta = -5
start_gcode = G28 ; home all axes\nG1 Z5 F5000 ; lift nozzle
start_perimeters_at_concave_points = 0
start_perimeters_at_non_overhang = 0
support_material = 
support_material_angle = 0
support_material_enforce_layers = 0
support_material_extruder = 1
support_material_extrusion_width = 0
support_material_interface_extruder = 1
support_material_interface_layers = 3
support_material_interface_spacing = 0
support_material_pattern = honeycomb
support_material_spacing = 10
support_material_speed = 120
support_material_threshold = 0
temperature = 195
thin_walls = 1
threads = 4
toolchange_gcode = 
top_infill_extrusion_width = 0
top_solid_infill_speed = 60
top_solid_layers = 3
travel_speed = 130
use_firmware_retraction = 0
use_relative_e_distances = 0
vibration_limit = 10
wipe = 0
z_offset = 0
Anything wrong with these settings?



*Update :

I noticed some play between the spindle and the copper nut of the Z-axis. The Nut itself sits definitely play-free inside the z-axle-carrier, but I can move the spindle about 0,1 - 0,2 mm in every direction. Maybe the tolerances are too high? Does it have to be play-free?
Attachments
20140510_143414.jpg

Legion 2.3
Posts: 84
Joined: Sun Apr 20, 2014 6:23 pm

Post by Legion 2.3 »

Now i`m sure that the z-axis-stepper is loosing steps: after a print, i manually turned the z-axis to 0mm with Repetier Host, but the nozzle was about 1 mm above the the printbed.
20140523_222217.jpg
It also happens with different materials:
20140523_222244.jpg
I´ve already done the following:

- checking the m3-set-screw of the Z-axis
- cleaning the linear bearings with alcohol and applying teflon-spray on them
- cleanining the Z-axis-spindle with alcohol and applying long-life-grease on it (Liqui Moly LM47 MoS2)
- readjusting the spindle
- setting the maximum Z - speed down to 60 %
- setting the Z-axis-current up and down ( currently set to about 150 %, motor is at 40 - 50 °C))
- printing with different filaments
- setting the retraction up to 0.2 mm (otherwise, it scrapes over the printed part )

So it´s definitely a problem with the z-axis and only with the z-axis, i got no drift of the X- or Y-axes. If i print multiple parts at once, the horizontal lines appear at every part at the same height, so it´s not a problem with the extruder.

I really don´t know what i can do anymore.

Anybody out there with ideas? :|

Dreide
Posts: 176
Joined: Sun Sep 29, 2013 12:32 am
Location: Lausanne, Switzerland

Post by Dreide »

First check, while the printer is switched off, if the spindle can be rotated by hand without effort. Assuming that is the case, reconnect the wires at the PCB (in order to be sure that they are firmly connected), visually inspect the PCB for conductive debris, especially around the Z motor driver, noddle a little bit at the wires, especially where they go into the motor. If all this does not help, it will be getting complicated. Obviously, the problem is hard to debug because of its intermittent occurrence. You might need to contact support at FelixPrinters and see what can be done to get it fixed.
Felix 2.0->3.0dual * Repetier (host+firmware) * KISSlicer Pro, Simplify3D * Cubify Design

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