Small Detail Extruder

Hi-

I recently switched out my .35mm hotend for a .25mm one.

Its generally working well, but small details (<~5mm) isnt the best. My printer can move to accuracies within 0.05-0.1mm accuracy, but small details come out dirty. How can I fix this.

CONFIG File for Slic3r:

layer_height = .15
max_fan_speed = 100
min_fan_speed = 35
min_print_speed = 10
min_skirt_length = 0
notes =
nozzle_diameter = .25
only_retract_when_crossing_perimeters = 0
output_filename_format = [input_filename_base].gcode
perimeter_acceleration = 25
perimeter_extruder = 1
perimeter_extrusion_width = 0
perimeter_speed = 30
perimeters = 2
post_process =
print_center = 75,75
randomize_start = 1
retract_before_travel = 2
retract_length = 1
retract_length_toolchange = 3
retract_lift = 0
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 = 15
small_perimeter_speed = 30
solid_fill_pattern = rectilinear
solid_infill_below_area = 75
solid_infill_every_layers = 0
solid_infill_speed = 60
start_gcode = G28 ; home all axes
support_material = 1
support_material_angle = 0
support_material_extruder = 1
support_material_extrusion_width = 0
support_material_pattern = rectilinear
support_material_spacing = 2
support_material_speed = 60
support_material_threshold = 45
temperature = 188
threads = 2
top_solid_infill_speed = 50
top_solid_layers = 3
travel_speed = 130
use_relative_e_distances = 0
vibration_limit = 0
z_offset = 0

Any advice or ideas are greatly appreciated.

-Nick

Edited 1 time(s). Last edit at 01/13/2013 12:54PM by N314.

Have any pics? I'm running a .25mm nozzle, .1mm layer, and getting pretty good detail. The fingers in this image are about .6-.75mm.

What height:width ratio are you running (or are you allowing Slic3r to decide?) ?

Dirty Steve Wrote:
-------------------------------------------------------
> Have any pics? I'm running a .25mm nozzle, .1mm
> layer, and getting pretty good detail. The fingers
> in this image are about .6-.75mm.


wow. Now I want a .25 nozzle on my next build.... Nice.
Curious if that's ABS or PLA and 1.75 or 3mm filament?

There is a limit to the level of detail that can be acheived using FDM. It has a lot to do with the viscosity of the material when it is being laid down. As you print, and the nozzle moves around, it tugs at the plastic, causing the details to blur.

Yes, you can go to a finer layer height, but you have the bed, and each previous solidified layer to help keep everything in place. There is no such mechanisim for X and Y, so you are looking at something around 0.3mm as the smallest identifiable feature, regardless of the nozzle size. YMMV.

@xclusive585

ABS print

@ Dirty Steve

Can you send me the STL or a link to that hand so I can print a comparison?

-Nick

hand.stl

ABS/PLA quality is also a very important factor when printing small parts.
Cooling too!

---

Frédéric

Well ive been too busy to print the hand, but im starting to think small defects are more an entire print problem, not just small features.

I hot you can tell from the photos below that im not getting perfect nice faces, theres tiny defects that make it kook sorta messy in general.

What is causing this/can be done about said issue?

-Nick

Looks like Z-wobble.

Oh boy... ive been through that. Any suggestions you have for that... Ive tried every [somewhat easy] way in the book.

-Nick

I did have a set of helical cut aluminum couplers. They were designed for 5mm motor shaft and 8mm rod, but being in the US, I'm using 5/16" rod, so the couplers would not correctly center the rod to the motor shaft.

I ended up printing a rigid set of couplers and that almost completely removed Z-wobble on my machine.

It's a little hard to see in the first photo but are you getting an offset in the middle of your horizontal holes, but not dropping stepps during printing? If so that would be backlash.

//It's a little hard to see in the first photo but are you getting an offset in the middle of your horizontal holes, but not dropping stepps during printing? If //so that would be backlash.

If it is back lash ill find out soon. This weekend i was planning on replacing my 5mm belts with GT2's.

Also what about those tiny stringy defects. Would those be possibly caused by backlash?

-Nick

The GT2 belts will help. I recently switched from T5 as well.

Stringing is usually caused noozle ooze. Maybe lower your temperature a little. One thing that would help Slic3r would be if they added a wipe function. KISSlicer and Skeinforge that will wipe the nozzle inside the print before moving to another print area. Maybe if your extruder gears have a lot of play between each other it could be some extruder backlash, but I've not read or seen anywhere of extruder backlash being an issue for anyone.

Stringing issues vary by materials and hot end designs.