wavy prints

This topic contains 18 replies, has 5 voices, and was last updated by  80486 6 months, 2 weeks ago.

Viewing 19 posts - 1 through 19 (of 19 total)
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  • #35003

    80486
    Participant

    I’m having really good adhesion, but my prints are coming out wavy. does anyone have an idea as to why? I currently don’t have a computer controlled fan hooked up, perhaps that why or part of the reason.

    Material: PLA
    Hotend Temp: 210 first layer, 205 other layers
    Bed temp: 60
    firmware: Marlin 1.1.0-1
    link to model printed: http://www.thingiverse.com/thing:1711753

    Slic3r settings:
    $ cat filament/HatchBox\ PLA\ 1.75\ Black.ini

    # generated by Slic3r 1.2.9 on Sat Apr 22 23:48:03 2017
    bed_temperature = 60
    bridge_fan_speed = 90
    cooling = 1
    disable_fan_first_layers = 1
    extrusion_multiplier = 1
    fan_always_on = 0
    fan_below_layer_time = 55
    filament_colour = #FFFFFF
    filament_diameter = 1.75
    first_layer_bed_temperature = 60
    first_layer_temperature = 210
    max_fan_speed = 100
    min_fan_speed = 60
    min_print_speed = 12
    slowdown_below_layer_time = 18
    temperature = 205

    $ cat print/MPCNC.ini

    # generated by Slic3r 1.2.9 on Mon Mar 6 00:23:55 2017
    avoid_crossing_perimeters = 1
    bottom_solid_layers = 3
    bridge_acceleration = 0
    bridge_flow_ratio = 1
    bridge_speed = 25
    brim_width = 0
    complete_objects = 0
    default_acceleration = 0
    dont_support_bridges = 1
    external_fill_pattern = rectilinear
    external_perimeter_extrusion_width = 0
    external_perimeter_speed = 80%
    external_perimeters_first = 0
    extra_perimeters = 1
    extruder_clearance_height = 20
    extruder_clearance_radius = 20
    extrusion_width = 0
    fill_angle = 45
    fill_density = 40%
    fill_pattern = rectilinear
    first_layer_acceleration = 0
    first_layer_extrusion_width = 100%
    first_layer_height = 0.32
    first_layer_speed = 35%
    gap_fill_speed = 18
    gcode_comments = 0
    infill_acceleration = 0
    infill_every_layers = 1
    infill_extruder = 1
    infill_extrusion_width = 0
    infill_first = 0
    infill_only_where_needed = 0
    infill_overlap = 15%
    infill_speed = 26
    interface_shells = 0
    layer_height = 0.2752
    max_print_speed = 80
    max_volumetric_speed = 0
    min_skirt_length = 4
    notes =
    only_retract_when_crossing_perimeters = 0
    ooze_prevention = 0
    output_filename_format = [input_filename_base].gcode
    overhangs = 1
    perimeter_acceleration = 0
    perimeter_extruder = 1
    perimeter_extrusion_width = 0
    perimeter_speed = 25
    perimeters = 3
    post_process =
    raft_layers = 0
    resolution = 0
    seam_position = nearest
    skirt_distance = 4
    skirt_height = 1
    skirts = 2
    small_perimeter_speed = 100%
    solid_infill_below_area = 70
    solid_infill_every_layers = 0
    solid_infill_extruder = 1
    solid_infill_extrusion_width = 0
    solid_infill_speed = 95%
    spiral_vase = 0
    standby_temperature_delta = -5
    support_material = 0
    support_material_angle = 0
    support_material_contact_distance = 0.2
    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_interface_speed = 100%
    support_material_pattern = pillars
    support_material_spacing = 2.5
    support_material_speed = 22
    support_material_threshold = 0
    thin_walls = 1
    threads = 4
    top_infill_extrusion_width = 0
    top_solid_infill_speed = 90%
    top_solid_layers = 3
    travel_speed = 48
    xy_size_compensation = 0

    $ cat printer/Simple\ Mode.ini

    # generated by Slic3r 1.2.9 on Fri Mar 3 13:51:39 2017
    bed_shape = 0x0,200x0,200x200,0x200
    before_layer_gcode =
    end_gcode = G91\nG1 E-5 ;retract\nG1 Z10 ;lift up 10mm\nG90\nM104 S0 ; turn off temperature\nM84 ; disable motors
    extruder_offset = 0x0
    gcode_flavor = reprap
    layer_gcode =
    nozzle_diameter = 0.4
    octoprint_apikey =
    octoprint_host =
    pressure_advance = 0
    retract_before_travel = 2
    retract_layer_change = 0
    retract_length = 1
    retract_length_toolchange = 10
    retract_lift = 0
    retract_restart_extra = 0
    retract_restart_extra_toolchange = 0
    retract_speed = 30
    start_gcode =
    toolchange_gcode =
    use_firmware_retraction = 0
    use_relative_e_distances = 0
    use_volumetric_e = 0
    vibration_limit = 0
    wipe = 0
    z_offset = 0

    $ cat printer/Simple\ Mode.ini

    # generated by Slic3r 1.2.9 on Fri Mar 3 13:51:39 2017
    bed_shape = 0x0,200x0,200x200,0x200
    before_layer_gcode =
    end_gcode = G91\nG1 E-5 ;retract\nG1 Z10 ;lift up 10mm\nG90\nM104 S0 ; turn off temperature\nM84 ; disable motors
    extruder_offset = 0x0
    gcode_flavor = reprap
    layer_gcode =
    nozzle_diameter = 0.4
    octoprint_apikey =
    octoprint_host =
    pressure_advance = 0
    retract_before_travel = 2
    retract_layer_change = 0
    retract_length = 1
    retract_length_toolchange = 10
    retract_lift = 0
    retract_restart_extra = 0
    retract_restart_extra_toolchange = 0
    retract_speed = 30
    start_gcode =
    toolchange_gcode =
    use_firmware_retraction = 0
    use_relative_e_distances = 0
    use_volumetric_e = 0
    vibration_limit = 0
    wipe = 0
    z_offset = 0

    #35010

    Barry
    Participant

    Lets see a picture of the cnc. Looks like you’re running too fast.

    1 user thanked author for this post.
    #35014

    Ryan
    Keymaster

    I agree 70-80 is pretty fast.

    Try 30mm/s to get everything dialed in then see how far you can go, depending on the size of your machine. PLA really needs a fan for parts this small. and Those temps might be too high as well, depends on your filament but I use 196 for hatchbox.

    1 user thanked author for this post.
    #35017

    Kevin Lopez
    Participant

    I agree with everyone else it does look too fast. My mpcnc begins to sound like it is going to disassemble itself any faster than 45mm/s. If you’re using an mk8 extruder, not only can the mpcnc not move that fast, it also has a somewhat lack luster flow rate. By this, I mean it can only extrude so much plastic at once. With my 1mm nozzle I have to print at 20mm/s because the extruder begins to under extrude severely any faster.

    #35019

    Ryan
    Keymaster

    Kevin you should swap out the throat and try 3mm filament. That will give you the pressure and volume you need for such a large nozzle.

    #35026

    Kevin Lopez
    Participant

    Hmm, I learned from many others that a smaller diameter is better for high volume. Something about more surface area per volume of plastic, so it is able to be brought up to heat faster. I was thinking of getting an e3d volcano or a clone to try out one day. With my black PLA, the more time the plastic has to “heat up”, the shinier the layers look. On my thick nozzle prints, the plastic is more matte. I counteract a little w/ higher temp.

    #35031

    80486
    Participant

    because Barry asked for a picture of the printer itself, I’ve included a couple. I’ve brought down the speed to 30 first and we’ll see how much that improves it. I’ll report back with pictures when it’s done.

    #35039

    Barry
    Participant

    Yea, slowing down will help. There’s some diagonal braces on thingiverse that may help too. Though with the mass of the extruder hanging down that low, you’re not going to be able to print too fast.

    #35049

    80486
    Participant

    OK, here’s the latest.

    I reran the print, but changed the max_print_speed option in Slic3r from 80 to 30. This didn’t seam to change the movement of the machine much, and the print came out about the same. Did I change the wrong setting perhaps? in the image I’ve included, the part pictured before is on the left, the new on after the change is on right.

    I’m going to try the same print again, only this time attach the fan and bring the temp down to 196 and see if that has an effect. I’ll update again when it’s done.

    #35056

    Barry
    Participant

    Yea, you changed the wrong setting. Here’s my slow settings for my rostock max delta, should work for you as well. The Max speed setting is only if you’re using percentages for print speeds. It’s kind of a weird setting. Use my settings, then you can adjust up as you print other things until you start getting crappy prints again, then go back to the last good setting.

    Attachments:
    #35078

    80486
    Participant

    OK, I’ve run 2 new prints now.

    the first, all I did was hook up the print fan, and bring the extruder temp down to 196. this didn’t seam to change the print at all. I didn’t bother taking a picture. strangely, the fan never did kick on throughout the print. I know it’s hooked up right however, as running the gcode M106 S255 does kick the fan on.

    in the second print, I left the changes above and included the settings Barry gave above (see screenshot). this actually increased the print speed by a significant amount. however, the total print time was increased by about 8 minutes too, but it’s not clear where that extra time is from. the print is still in progress, but it appears it hasn’t changed the quality much if at all, except for some new stringing in between travels. I included a picture of the print as it looks now, at about 1/3 of the way through.

    #35092

    Ryan
    Keymaster

    All three jumpers are under your extruder stepper driver? You set the stepper driver voltage to 0.6V?

    I have attached a small test print.

    #35102
    I agree with everyone else it does look too fast. My mpcnc begins to sound like it is going to disassemble itself any faster than 45mm/s. If you’re using an mk8 extruder, not only can the mpcnc not move that fast, it also has a somewhat lack luster flow rate. By this, I mean it can only extrude so much plastic at once. With my 1mm nozzle I have to print at 20mm/s because the extruder begins to under extrude severely any faster.

    An easy fix for that is to change the stepper motor for a bigger one and to crank up a bit the stepper driver current. Also, you can set a higher temperature. I’ve done both on my machine, it works great even at high speeds.

    1.75mm filament works pretty well with 1.0 or 1.2mm nozzles. I never actually tried 3mm but I would worry that the extruder would have to push with way more force to get it through the nozzle, despite the lowest speed. Anyway, your problem is not due to that, I second what Ryan just said , check your jumpers, it looks like you may not be in 1/32 step mode.

    I suggest you to watch closely whenever your machine prints. If you stare at whatever it is doing the whole time, you will end up to find out the cause eventually.

    #35118

    80486
    Participant
    All three jumpers are under your extruder stepper driver? You set the stepper driver voltage to 0.6V?

    I have attached a small test print.

    I printed the test and put some pictures up. print looks awesome, except for the large flat surface, it has minor waving it looks like. certainly not as pronounced as it is in the strap from before.

    I have 3 jumpers in (pretty sure. it’s been a while since I put the stepper controllers in) I also set the stepper driver voltage.

    I do have one idea myself. When I put together the bed, I put 3 screws in with a spring and let the bed rest on the table using the screws as legs (some pictures of the bed before: http://imgur.com/a/JbQn5). this caused the prints to lean on the Y axis. to address this, I got some longer screws (about 2 inches) and drilled all the way through the table and put a nut on the underside. this is how the bed is anchored currently. pictures of the setup: http://imgur.com/a/hLAdS it feels stable when you grab it, but the bed might vibrate differently than the table or machine. perhaps I should put threaded inserts or wood glue into the holes I drilled, instead of letting it hang loose. the nuts are also not locknuts, but I suspect that will just affect my leveling, not allow the bed to move.

    #35123

    Well on the pictures the waving looks more major than minor…

    Your build plate could be the reason, since it is not secured in place. For now, try to isolate the cause, I suggest you to remove it and replace it by some random mirror or glass plate, directly secured to the table with no adjustment.
    Then try to print on this and see if you still have the issue. With PLA you don’t need a hot plate anyway as long as it is a relatively small part, glue stick is enough.
    Trust me on this, I’ve printed fairly big stuff with PLA without any hot plate, it works fine.

    #35124

    Ryan
    Keymaster

    After seeing the machine, My best guess is too tall, loose belts, and the filament pulling on the head.

    Sorry but that build is huge in every direction. You would have a much more enjoyably time with a more manageable size. There are things you can do to make a big build work but it is much easier to learn on something much smaller.

    If you are going to stick with that size, brace the legs, and use a bowden tube to feed the filament top eliminate pulling torque, probably slow down a bit more on the print speed as well..

    #35149

    80486
    Participant
    Well on the pictures the waving looks more major than minor…

    Your build plate could be the reason, since it is not secured in place. For now, try to isolate the cause, I suggest you to remove it and replace it by some random mirror or glass plate, directly secured to the table with no adjustment.
    Then try to print on this and see if you still have the issue. With PLA you don’t need a hot plate anyway as long as it is a relatively small part, glue stick is enough.
    Trust me on this, I’ve printed fairly big stuff with PLA without any hot plate, it works fine.

    yeah I think this is the best idea for now. at least it’s the least drastic. shrinking the size of the printer is a pretty big project. for the record, I know the machine is on the big side of things. it’s 20″ x 20″ x 8″.

    #35151

    Ryan
    Keymaster

    All my build plates float really loosely, I do this in case I crash the head. I don’t see how this could be the issue, there should be very little force on the bed in any direction, even more so since it doesn’t move.

    #35154

    80486
    Participant

    I’m not concerned with wobble in the z axis, but in the x/y. If you grab it with your hand and wiggle it does move a little, but it’s pretty stable and requires a decent amount of force. Certainly better than it was before I actually bolted it to the table.

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