Cannot print a bar...ends keep curling up

Wow I`m battling with this print and have given up for now, 15 tries ans no luck, with ALL kinds of settings
I`m trying to print a special bar for my OROD but no luck, the bar is 180x25x8mm
The problem is that after about the 5th layer the ends start to curl up, and it just keep getting worse, eventually by layer 10 I have to stop then both ends are standing up in the air and curling up 2 or 3mm..
The bed temperature is 70 degrees, I`ve tried to print from 180 to 205 degrees
The prints start of perfect, adhering very well to the kapton, but then as the layers progress the ends start to curl up, this is my last attempt
Even placing 5 perimeter lines, then fill in at 25%... I suspect that the ends curl up due to the PLA getting cold, the interior is hotter than the edges and the bed cools down to the edges.... it could also be the way the PLA cools, faster on the edges and less in the middle, I think the desig is also a problem, It is a pure bar and sqare, I will add some feet to the ends just to spread the stresses and see what gives

; avoid_crossing_perimeters = 1
; bed_shape = 0x0,200x0,200x200,0x200
; bed_temperature = 0
; before_layer_gcode =
; bridge_acceleration = 0
; bridge_fan_speed = 100
; brim_width = 0
; complete_objects = 0
; cooling = 1
; default_acceleration = 0
; disable_fan_first_layers = 3
; duplicate_distance = 6
; end_gcode = M104 S0 ; turn off temperature\nG28 X0 ; home X axis\nM84 ; disable motors\n
; extruder_clearance_height = 20
; extruder_clearance_radius = 20
; extruder_offset = 0x0
; extrusion_axis = E
; extrusion_multiplier = 1
; fan_always_on = 0
; fan_below_layer_time = 60
; filament_diameter = 1.75
; first_layer_acceleration = 0
; first_layer_bed_temperature = 0
; first_layer_extrusion_width = 200%
; first_layer_speed = 40%
; first_layer_temperature = 200
; gcode_arcs = 0
; gcode_comments = 0
; gcode_flavor = reprap
; infill_acceleration = 0
; infill_first = 0
; layer_gcode =
; max_fan_speed = 100
; min_fan_speed = 35
; min_print_speed = 10
; min_skirt_length = 0
; notes =
; nozzle_diameter = 0.5
; only_retract_when_crossing_perimeters = 0
; ooze_prevention = 0
; output_filename_format = [input_filename_base].g
; perimeter_acceleration = 0
; post_process =
; pressure_advance = 0
; resolution = 0
; retract_before_travel = 2
; retract_layer_change = 1
; retract_length = 5
; retract_length_toolchange = 10
; retract_lift = 0.5
; retract_restart_extra = 1
; retract_restart_extra_toolchange = 0
; retract_speed = 30
; skirt_distance = 3
; skirt_height = 1
; skirts = 1
; slowdown_below_layer_time = 5
; spiral_vase = 0
; standby_temperature_delta = -5
; start_gcode = ;G28 ; home all axes\nG1 Z5 F5000 ; lift nozzle\nM563 P0 D0 H1
; temperature = 200
; threads = 2
; toolchange_gcode =
; travel_speed = 250
; use_firmware_retraction = 0
; use_relative_e_distances = 0
; use_volumetric_e = 0
; vibration_limit = 0
; wipe = 0
; z_offset = 0
; dont_support_bridges = 0
; extrusion_width = 0
; first_layer_height = 0.15
; infill_only_where_needed = 0
; interface_shells = 0
; layer_height = 0.25
; raft_layers = 0
; seam_position = nearest
; 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 = 0
; support_material_interface_spacing = 0
; support_material_interface_speed = 100%
; support_material_pattern = rectilinear
; support_material_spacing = 2.5
; support_material_speed = 40
; support_material_threshold = 0
; xy_size_compensation = 0
; bottom_solid_layers = 1
; bridge_flow_ratio = 1
; bridge_speed = 45
; external_fill_pattern = rectilinear
; external_perimeter_extrusion_width = 0
; external_perimeter_speed = 45
; external_perimeters_first = 1
; extra_perimeters = 1
; fill_angle = 45
; fill_density = 25%
; fill_pattern = rectilinear
; gap_fill_speed = 10
; infill_every_layers = 1
; infill_extruder = 1
; infill_extrusion_width = 0
; infill_overlap = 5%
; infill_speed = 80
; overhangs = 1
; perimeter_extruder = 1
; perimeter_extrusion_width = 0
; perimeter_speed = 40
; perimeters = 5
; small_perimeter_speed = 32
; solid_infill_below_area = 70
; solid_infill_every_layers = 0
; solid_infill_extruder = 1
; solid_infill_extrusion_width = 0
; solid_infill_speed = 40
; thin_walls = 1
; top_infill_extrusion_width = 0
; top_solid_infill_speed = 40
; top_solid_layers = 3

Yip that solved the issue, I added two bars to the end and voila no more curling, I will cut these off and then the bar will be usable..
I also found that printing the fill slower help as well..

I also cleaned the Kapton with FLUX CLEANER, it seems to become more sticky E191/1 flux cleaner. HANDLE WITH CARE, its poisonous

90% Alcohol seems to make it very slippery and toooo clean.

Thx Ben

A few suggestions:

1. 70C bed temperature is rather high for printing PLA. I use 65C when printing direct on glass, and 55C on other surfaces.

2. Depending on what fan and ducting you have on the hot end (which has changed more than once since the Ormerod was introduced), there may be a lot of backwash from the fan. So put your hand behind the fan, and if you can feel a draught coming from the fan, print and fit a fan inlet duct to eliminate the backwash. The backwash is known to cause warping of that part of the print behind the fan.

3. Also shield the printer from any draughts in the room.

---

Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

yes indeed LOTs of backwash! !
I actually thought the fan was blowing the wrong direction, turned it around once.
Never thought it had such a big impact on prints.
What is the purpose of the fan? I can suppose to cool the head to maintain a steady temp; but is it used to cool the printed parts' pla As it is printed?
Where can I get a fan duct inlet, not sure what they are supposed to look like
Thanks for the info it really help.... things are coming together. Thanks for sharing with us rookies
*cleaning the kapton with pcb FLuX REALY worked. Boy I battled to get that part from the kapton. The Acid in the flux seems to make the kapton quite sticky, I got the 50mm wide type, the 20mm is to narrow... I'm still looking for the 200mm rolls. Not available in RSA though. ..
tx Ben

The most important function of the fan is to keep the top end of the nozzle assembly cool. Otherwise, the filament melts too far up and jams the nozzle.

A secondary purpose of the fan is to cool the print area immediately below the nozzle when you are printing PLA. This helps with bridging and overhangs. The older Ormerod designs have ducting to direct air at the tip of the nozzle for this purpose.

The fan inlet duct design I use is here [www.thingiverse.com].

---

Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

I haven't used Kapton tape for more than a year now - I use 'extreme hold' hairspray straight on the glass for PLA and haven't needed anything else since I started that. I found the Kapton was difficult to source, expensive when you could, was difficult to apply nicely and caused artifacts on the print - pieces dislodging and sticking to the print, or causing little lines from accidental overlaps.

Quote
VortyZA
I haven't used Kapton tape for more than a year now - I use 'extreme hold' hairspray straight on the glass for PLA and haven't needed anything else since I started that. I found the Kapton was difficult to source, expensive when you could, was difficult to apply nicely and caused artifacts on the print - pieces dislodging and sticking to the print, or causing little lines from accidental overlaps.

I am considering this, how much hairspray do you apply? A thin mist/film or do you make the glass quite 'wet'? Secondly do you do this when the bed is hot or cold? Lastly do you clean off and reapply the hairspray after every print?

Quote
VortyZA
I haven't used Kapton tape for more than a year now - I use 'extreme hold' hairspray straight on the glass for PLA and haven't needed anything else since I started that. I found the Kapton was difficult to source, expensive when you could, was difficult to apply nicely and caused artifacts on the print - pieces dislodging and sticking to the print, or causing little lines from accidental overlaps.

I used to find applying the 25mm Kapton tape a pain, with my shaky hands overlaps were a for gone conclusion. It was also quite expensive,
but then I found it in 200mm wide rolls on ebay and bought one for about £17
I have since found it here [www.ebay.co.uk]
for only £12.75 for a 100 foot roll Thats less than 13 pence per application ( I change it about once every 3 weeks so thats 6 years worth for £12.75 , great value)

As for applying it , thats a piece of cake , Firstly because of its width there is no need for overlaps or gaps , it goes on in one piece,
Just wet the glass with soapy water and the film will go on completely flat and smooth . Get it wrong and it lifts off easily to try again
Once its in place squeegy out the water with an old credit card . You will find while its wet it want to curl up at the edges so place a sheet of copy paper on the ally heat spreader and place the glass on top ( kapton side down)
and set the bed to about 40 degrees . The weight of the glass holds the edges down and the bed dries the water out .
You can change the Kapton and be up and running again in less than an hour .

It works for me

Don

Hi All
Some more ways to print on KAPTON TAPE
I battled for an hour to get the PLA to stick to the KAPTON, BUT NO GO !!
The I decided to try something else, I sprayed the KAPTON with Urethane Seal Coat (USC), on the hot surface, 56 degreesC, it is the stuff that is used to coat PCB`s against corrosion, we simply call it con formal coating
VOILA the PLA sticks like crazy !!
I really battle to pull the print off afterward, so good news there !! I suppose once then bed gets cold it would be easier
*The USC dries in a matter of seconds, 10 seconds and you are ready to go....
Hope this helps someone out there

Ps. the KAPTON soapy water application method ROCKs, it is really smooth and it gives me something to so with my old Credit Cards )) they seconds as REALLY good squeegees !!

Tx Ben