Slic3r settings for high quality, low-warp, high-strength printing of polycarbonate without an enclosure on a Prusa i3 MK2S

Polycarbonate.ini

# generated by Slic3r 1.37.2-prusa3d on Thu Dec  7 09:48:20 2017
# Figured out by trial and error engineer metacollin
# Released as public domain.	
# USE GLUESTICK FOR PRINT BED ADHESION
avoid_crossing_perimeters = 0
bed_shape = 0x0,250x0,250x210,0x210
bed_temperature = 110
before_layer_gcode = ;BEFORE_LAYER_CHANGE\n;[layer_z]\n\n
bottom_solid_layers = 8
bridge_acceleration = 1000
bridge_angle = 0
bridge_fan_speed = 40
bridge_flow_ratio = 0.8
bridge_speed = 20
brim_width = 0
clip_multipart_objects = 1
complete_objects = 0
cooling = 1
default_acceleration = 1000
deretract_speed = 30
disable_fan_first_layers = 3
dont_support_bridges = 1
duplicate_distance = 6
elefant_foot_compensation = 0
end_filament_gcode = "; Filament-specific end gcode"
end_gcode = G4 ; wait\nM104 S0 ; turn off temperature\nM140 S0 ; turn off heatbed\nM107 ; turn off fan\nG1 X0 Y200; home X axis\nM84 ; disable motors
ensure_vertical_shell_thickness = 0
external_fill_pattern = rectilinear
external_perimeter_extrusion_width = 0.6
external_perimeter_speed = 50
external_perimeters_first = 0
extra_perimeters = 0
extruder_clearance_height = 20
extruder_clearance_radius = 20
extruder_colour = #F8CE09
extruder_offset = 0x0
extrusion_axis = E
extrusion_multiplier = .93 ; You will probably need to adjust this.
extrusion_width = 0.9
fan_always_on = 0
fan_below_layer_time = 10
filament_colour = #3A80CA
filament_cost = 0
filament_density = 0
filament_diameter = 1.75
filament_max_volumetric_speed = 13
filament_notes = "Tested on eSun ePC and Priline Polycarbonate filaments.  Use gluestick for printbed adhesion."
filament_settings_id = Polycarbonate
filament_soluble = 0
filament_type = ABS
fill_angle = 45
fill_density = 40%
fill_pattern = honeycomb
first_layer_acceleration = 1000
first_layer_bed_temperature = 100
first_layer_extrusion_width = 0.6
first_layer_height = 0.2
first_layer_speed = 40
first_layer_temperature = 260
gap_fill_speed = 40
gcode_comments = 0
gcode_flavor = reprap
infill_acceleration = 2000
infill_every_layers = 1
infill_extruder = 1
infill_extrusion_width = 0.9
infill_first = 0
infill_only_where_needed = 0
infill_overlap = 7%
infill_speed = 75
interface_shells = 0
layer_gcode = ;AFTER_LAYER_CHANGE\n;[layer_z]
layer_height = 0.2
max_fan_= 20
max_layer_height = 0.25
max_print_speed = 100
max_volumetric_extrusion_rate_slope_negative = 0
max_volumetric_extrusion_rate_slope_positive = 0
max_volumetric_speed = 12
min_fan_speed = 20
min_layer_height = 0.07
min_print_speed = 3
min_skirt_length = 4
notes = "Tested on eSun ePC and Priline Polycarbonate filaments. Use gluestick for printbed adhesion."
nozzle_diameter = 0.4
octoprint_apikey = 
octoprint_host = 
only_retract_when_crossing_perimeters = 0
ooze_prevention = 0
output_filename_format = [input_filename_base].gcode
overhangs = 1
perimeter_acceleration = 800
perimeter_extruder = 1
perimeter_extrusion_width = 0.9
perimeter_speed = 65
perimeters = 4
post_process = 
print_settings_id = 0.200mm FAST LA Polycarbonate
printer_notes = "Tested on eSun ePC and Priline Polycarbonate filaments.  Use gluestick for printbed adhesion."
printer_settings_id = Original Prusa i3 MK2 - PC
raft_layers = 0
resolution = 0
retract_before_travel = 1
retract_before_wipe = 0%
retract_layer_change = 1
retract_length = 1
retract_length_toolchange = 3
retract_lift = 0.5
retract_lift_above = 1
retract_lift_below = 199
retract_restart_extra = 0
retract_restart_extra_toolchange = 0
retract_speed = 35
seam_position = random
serial_port = 
serial_speed = 115000
single_extruder_multi_material = 0
skirt_distance = 3
skirt_height = 2
skirts = 2
slowdown_below_layer_time = 15
small_perimeter_speed = 30
solid_infill_below_area = 0
solid_infill_every_layers = 0
solid_infill_extruder = 1
solid_infill_extrusion_width = 0
solid_infill_speed = 70
spiral_vase = 0
standby_temperature_delta = -5
start_filament_gcode = "M900 K50 ; Filament gcode"
start_gcode = M115 U3.1.0 ; tell printer latest fw version\nM83  ; extruder relative mode\nM104 S[first_layer_temperature] ; set extruder temp\nM140 S[first_layer_bed_temperature] ; set bed temp\nM190 S[first_layer_bed_temperature] ; wait for bed temp\nM109 S[first_layer_temperature] ; wait for extruder temp\nG28 W ; home all without mesh bed level\nG80 ; mesh bed leveling\nG1 Y-3.0 F1000.0 ; go outside print area\nG92 E0.0\nG1 X60.0 E9.0  F1000.0 ; intro line\nG1 X100.0 E12.5  F1000.0 ; intro line\nG92 E0.0
support_material = 0
support_material_angle = 0
support_material_buildplate_only = 0
support_material_contact_distance = 0.2
support_material_enforce_layers = 0
support_material_extruder = 0
support_material_extrusion_width = 0.35
support_material_interface_contact_loops = 0
support_material_interface_extruder = 0
support_material_interface_layers = 2
support_material_interface_spacing = 3
support_material_interface_speed = 100%
support_material_pattern = rectilinear
support_material_spacing = 4
support_material_speed = 60
support_material_synchronize_layers = 0
support_material_threshold = 1
support_material_with_sheath = 0
support_material_xy_spacing = 60%
temperature = 260
thin_walls = 0
threads = 56
toolchange_gcode = 
top_infill_extrusion_width = 0.44
top_solid_infill_speed = 50
top_solid_layers = 8
travel_speed = 120
use_firmware_retraction = 0
use_relative_e_distances = 1
use_volumetric_e = 0
variable_layer_height = 0
wipe = 1
wipe_tower = 0
wipe_tower_per_color_wipe = 15
wipe_tower_width = 60
wipe_tower_x = 180
wipe_tower_y = 140
xy_size_compensation = 0
z_offset = 0

Did you use these settings on a stock printer or did you make mods to it?

Incredible! this works with my printer, a Prusa MK3s, with a 0,4 mm nozzle. I did not changed anything on the settings. Just loaded the ini and print. I made several tests before and all warped. I was already thinking of building an enclosure. I could not find a solution and it is desperately that I tested this ini file. I do not understant what you put in it, but it works. The printing is very fast. Thank's a lot Metacollin.