waves in the Z axis

[krauli 0]

Hello,

I have a printer Prusa.

I made the change of the filament 3 mm by 1.75 mm but I have a problem I can not solve, the model have waves in the Z axis. The layers more "extrude" the other layers. As shown in the picture attached.

I use the Cura as slicing and settings are as follows:

layer_height = 0.075

wall_thickness = 1.2

retraction_enable = True

solid_layer_thickness = 0.6

fill_density = 30

nozzle_size = 0.4

print_speed = 10

print_temperature = 230

print_temperature2 = 0

print_temperature3 = 0

print_temperature4 = 0

print_bed_temperature = 110

support = None

platform_adhesion = None

support_dual_extrusion = False

wipe_tower = False

wipe_tower_volume = 15

ooze_shield = False

filament_diameter = 1.75

filament_diameter2 = 0

filament_diameter3 = 0

filament_diameter4 = 0

filament_flow = 100

retraction_speed = 40

retraction_amount = 5.0

retraction_dual_amount = 16.5

retraction_min_travel = 1

retraction_combing = True

retraction_minimal_extrusion = 0.01

retraction_hop = 0.0

bottom_thickness = 0.0

layer0_width_factor = 100

object_sink = 0.0

overlap_dual = 0.15

travel_speed = 100

bottom_layer_speed = 10

infill_speed = 30

inset0_speed = 0.0

insetx_speed = 0.0

cool_min_layer_time = 0

fan_enabled = True

skirt_line_count = 3

skirt_gap = 3.0

skirt_minimal_length = 150.0

fan_full_height = 0.5

fan_speed = 100

fan_speed_max = 100

cool_min_feedrate = 10

cool_head_lift = False

solid_top = True

solid_bottom = True

fill_overlap = 15

support_type = Grid

support_angle = 60

support_fill_rate = 15

support_xy_distance = 0.7

support_z_distance = 0.15

spiralize = False

simple_mode = False

brim_line_count = 15

raft_margin = 5

raft_line_spacing = 1.0

raft_base_thickness = 0.3

raft_base_linewidth = 0.7

raft_interface_thickness = 0.2

raft_interface_linewidth = 0.2

raft_airgap = 0.22

raft_surface_layers = 2

fix_horrible_union_all_type_a = True

fix_horrible_union_all_type_b = False

fix_horrible_use_open_bits = False

fix_horrible_extensive_stitching = False

plugin_config = (lp1

By the printer settings I use:

Acceleration: 200 in the X and Y and Z in 100

Steps / mm: 95

Jerk: 16.0

Z-Jerk: 0.2

Sorry my bad english

Klaus Maximilian

 

[gr5 2,067]

It could be either bad Z screw but if you didn't change the Z screw it is much more likely a temperature issue. Watch the temperature carefully while it prints. See if the temperature varies. It should be consistent within 1C.

The pattern you show is what I would expect with 10C to 15C swings in temperature.

 

[krauli 0]

Thank gr5

The temperature does not change much during printing.

Believes it may be something related to the steps / mm? because he changed the value after the exchange of 3mm filament to 1.75 mm

If yes, so how can I know the right value? today i use 95

 

[gr5 2,067]

I doubt it's steps per mm. You can calibrate it by marking the filament with a permanent marker, then moving the filament slowly forward (though a hot nozzle I guess) for 100mm. Then measuring how far the filament moved exactly. Adjust steps/mm to be = current value * ( 100mm / actual-distance-moved)

Then power cycle your machine to make sure the value was saved and repeat the test.

 

[gr5 2,067]

The pattern you are seeing is usually either Z screw or nozzle temp. I don't think it's possible to be anything else. I guess maybe on a delta.... but you said you had a Prusa.

So you say you watched the temperature carefully during one of those cycles (looks like maybe 10 layers)?

If it didn't change by more than 2C then it must be the Z screw. I don't remember how the prusa works - does the base move up and down? Or the nozzle? How many lead screws? Maybe the nut is loose? Try moving the bed up and down by 30mm repeatedly (maybe using pronterface) and feel the bed - see if the movement is smooth or wobbly. Look for horizontal movement *and* vertical speed up/slow down changes. What is the vertical spacing on your bands? What is the vertical spacing on the threads on your Z screw(s)?