Jump to content
Ultimaker Community of 3D Printing Experts
Sign in to follow this  
bingobob

ABS printing settings

Recommended Posts

Thanks to mrjohnk's post of his ABS printing parameters in this thread:

 

http://umforum.ultimaker.com/index.php?/topic/1789-retraction-and-blobs/

 

I was able to print an object in ABS that is the most successful that I have so far achieved.

 

I think it's worth repeating those parameters here for anyone struggling to print in ABS. I was experiencing a lot of blobbing, cracking and warping and thanks to those parameters, the first 2 at least are greatly improved.

 

I was getting a lot of failed prints from the first layer coming unstuck, but by not using the Cura raft and printing a solid 0.3mm base instead they seem to be sticking better.

 

Most of my problems come from Cura's support structure which I don't like. Here is an example:

 

photo1aue.jpg

 

Anyone know what causes this?

 

Sometimes this causes the print to fail (head picks up on the print and wipes it out). I don't really see a solution to this other than provide my own support structures in CAD.

 

 

Print looking good now. Updated to latest Marlin and changed settings. Thanks for the help. Link to pic below. Also changed the order of print to Perimeter > Infill > Loops in order to drop any potential blobs in the infill instead.

 

http://www.flickr.com/photos/8465641@N07/8581931440/in/photostream

 

[profile]

layer_height = 0.2

nozzle_size = 0.4

wall_thickness = .4

solid_layer_thickness = 0.4

fill_density = 20

skirt_line_count = 6

skirt_gap = 0

print_speed = 50

print_temperature = 255

support = Everywhere

enable_raft = False

filament_diameter = 2.97

filament_density = .92

machine_center_x = 100

machine_center_y = 100

retraction_min_travel = 2

retraction_speed = 30

retraction_amount = 3

retraction_extra = 0

travel_speed = 150

max_z_speed = 3.0

bottom_layer_speed = 40

cool_min_layer_time = 15

fan_enabled = True

bottom_thickness = 0

enable_skin = True

model_scale = 1.0

model_rotate_base = 0

flip_x = False

flip_y = False

flip_z = False

swap_xz = False

swap_yz = False

extra_base_wall_thickness = 0.0

cool_min_feedrate = 20

fan_layer = 1

fan_speed = 17

fan_speed_max = 75

raft_margin = 5

raft_base_material_amount = 100

raft_interface_material_amount = 100

support_rate = 25

support_distance = 0.5

infill_type = Line

solid_top = True

fill_overlap = 12

bridge_speed = 100

sequence = Perimeter > Infill > Loops

force_first_layer_sequence = False

joris = False

retract_on_jumps_only = True

enable_dwindle = False

dwindle_pent_up_volume = 0.4

dwindle_slowdown_volume = 5.0

retraction_enable = True

plugin_config =

hop_on_move = False

model_matrix = 1.0,0.0,0.0,0.0,1.0,0.0,0.0,0.0,1.0

object_sink = 0.0

 

Share this post


Link to post
Share on other sites

OK, that print above turned out like this:

photo1bst.jpg

The warping in the support structure wasn't limited to the support structure, but you can see where the wall of the cylinder has pulled in.

I printed this part again but instead of having a fill ratio of 20% I used 100% and the the print was MUCH better. Much less deformation. Even on the support structure which is a bit odd.

I realised that the support structure on the right was more deformed than on the left and I realised it was due to the standard fan ducting which blows more air to that side of the print (the nozzle not being centered on the fan) so I have printed out a new duct that is much more directional to see if that helps:

photo2rd.jpg

Share this post


Link to post
Share on other sites

a good way to make an ABS print stick better is taking some wasted ABS prints, cut it into small parts an solute it in acetone.

bring this solution onto your print surface with a brush an let it dry, now your first layer has a ABS bottom to stick on.

worked well for me with prints which kept refusing to stick to the heated bed

 

Share this post


Link to post
Share on other sites

Thanks for that, but my problem is not getting the parts to stick to the bed. In fact with the heated bed, the Kapton tape and the ABS goo the problem is getting the part off the bed afterwards!

My problem was the deformation at different levels.

I have made significant progress in this and the other problems I was having printing ABS and I am now much more confident about printing in ABS. More so than PLA which I have noticed also shows similar deformation, albeit less significant that in ABS.

Here is the above part printing correctly now:

correctlyprinting.jpg

The finished print:

finishedbrut.jpg

And the smoothed finished product:

finishedsmoothed.jpg

This is a PLA print showing deformation:

photo2cftb.jpg

Share this post


Link to post
Share on other sites

I'm still experimenting, but the best results I have had so far are with these parameters:

 


[profile]
filament_diameter = 2.97
nozzle_size = 0.4
wall_thickness = 0.8
retraction_enable = True
layer_height = 0.1
solid_layer_thickness = 0.8
fill_density = 100
print_speed = 50
print_temperature = 255
print_bed_temperature = 70
support = None
enable_raft = False
filament_density = 0.88
skirt_line_count = 2
skirt_gap = 4
retraction_min_travel = 2
retraction_speed = 30
retraction_amount = 2
retraction_extra = 0.0
travel_speed = 100
max_z_speed = 3
bottom_layer_speed = 30
cool_min_layer_time = 15
fan_enabled = True
bottom_thickness = 0
object_sink = 0.0
enable_skin = False
plugin_config = (lp1
.
model_matrix = 3.74939945666e-33,1.0,-1.22464679915e-16,1.0,3.74939945666e-33,6.12323399574e-17,6.12323399574e-17,-1.22464679915e-16,-1.0
extra_base_wall_thickness = 0.0
cool_min_feedrate = 10
fan_layer = 1
fan_speed = 20
fan_speed_max = 40
raft_margin = 5
raft_base_material_amount = 100
raft_interface_material_amount = 100
support_rate = 100
support_distance = 0.5
infill_type = Line
solid_top = True
fill_overlap = 15
bridge_speed = 80
sequence = Infill > Loops > Perimeter
force_first_layer_sequence = True
joris = False
retract_on_jumps_only = True
hop_on_move = False
Crucially, the preliminary process is this:

1. Paint kapton tape with ABS goo

2. Let dry

3. Preheat platform

4. Start printing the first layer (this is the solid raft that I add in CAD - see above)

5. As soon as the raft has finished printing (sooner even, if possible) turn the heating off

Let the printer print.

And most importantly - no cooling fan.

Share this post


Link to post
Share on other sites

>no cooling fan

It looks like it's on but set to a low value? This is from your printer settings:

fan_enabled = True

fan_speed = 20

fan_speed_max = 40

 

Share this post


Link to post
Share on other sites

It's physically unplugged.

Even with very low fan speeds, there is a large amount of warping and cracking between layers.

I think by not cooling and printing relatively slowly the material remains at its glass transition temp longer and kind of self-anneals if that makes any sense.

I think the cooling depends a lot of what kind of part you are printing. When I printed the thin-shelled ABS fan duct (see above) I used cooling and that printed just fine.

I still haven't really got my head around the science of it. The only thing I can think of left to try is enclosing the print volume and heating it to keep the temp inside at 70°C+. Not sure how the motors and belts will like that, though.

Share this post


Link to post
Share on other sites

Many people have done just that. They also usually move the x and y motors *outside* the box so they don't get hot. Other people seem to do the opposite with ABS I think maybe? They turn the heated bed off as soon as the first layer is done (like you).

The ones who "enclose" usually lower the heated bed by 10C after the first layer. The higher temp to get it to stick well, the lower temp so that it is solid where touching the bed but they keep it at the lower temp for the whole print. For PLA this is 70C and then 60C. I'm not sure what the values are for ABS.

I have a heated bed but haven't printed ABS yet. For PLA there is a *huge* difference between 60C and 70C (for me). There is a sudden change where suddenly the PLA sticks very very well. Then there is zero difference between 60C and 20C (room temperature).

I no longer use my heated bed because for PLA I found that blue tape rubbed with alcohol is pretty amazingly sticky and I haven't tried ABS yet.

Actually I used it a while back when printing an airplane only .4mm thick (2 layers). But other than that I don't use it anymore.

 

Share this post


Link to post
Share on other sites

Actually I used it a while back when printing an airplane only .4mm thick (2 layers). But other than that I don't use it anymore.

 

I may have mentioned it in an earlier thread when this came up - but I find that I get really good results for thin flat things, printing PLA at 230º directly onto polyimide tape on my non-heated bed.

It's hopeless for thick or tall objects as there's not enough long-term adhesion to resist warping and keep the object fixed for the duration of the print. But for objects with a large surface area, and only a few mm high it works really nicely.

 

Share this post


Link to post
Share on other sites

Good to know. Thanks. :)

I much prefer the mechanical properties of ABS to PLA. I find that the layers bond better, too. Plus you can finish the surface reasonably nicely, depending on the part you want.

I have also found that for long flat parts like the one you describe you can print directly onto the glass with the ABS goo. It doesn't stick as well as on Kapton, but you get a beautiful mirror finish to the bottom layer from the glass.

I don't have any heat control on my PCB. I need to wire something up. At the moment it's all or nothing. What do you use to control the temp?

Thanks.

Share this post


Link to post
Share on other sites

epcos 100k thermistor inside the aluminium bed and custom marlin firmware.

btw: can it be that kapton tape is a horrible heat conductor? downside temperature of my bed matches sensor readings, but printing surface upside is about 10 to 15 °C lower

 

Share this post


Link to post
Share on other sites

What might cause poor layer bonding when printing ABS? I used bingobob's printing settings (or something similar to it in the latest Cura 13.6.4) and recommendation of using abs glue, heated bed and kapton. I fixed the edge curling problem, so my corners are fine now. But the large object, iphone case actually, prints out with poor layer bonding and can be broken easily. I tried different infills, from 20 to 100%. Help much appreciated.

 

Share this post


Link to post
Share on other sites

Are you using cooling? If so, try not cooling. I get poor layer adhesion if I cool too quickly - or at all.

You could also try printing at a higher temperature, with a slower head speed. Maybe increase the amount that is extruded by lowering the value of the filament diameter.

Share this post


Link to post
Share on other sites

Sure, sorry for the bad photo.

The photo shows only printed Brim, I suggest when it started to print the model itself - print failed. I used retraction. Speed: 70mm/s and Distance:4.5mm

By the way, have you tried Cura's fast print ABS profiles? And what is your heated bed temperature? I try keeping it around 100-110 for the brim layers, and then turn it off.

f33e2f2b58c7e22f53aeb021e0607f93.jpeg

 

Share this post


Link to post
Share on other sites

What does your very first layer look like? It looks like it might be starting to print too far above the bed. If the first layer isn't good then the rest will fail. I always print a double skirt around the object and while it's printing that I manually turn the Z-axis so that the first layer is being pressed solidly into the bed. I raise the bed too far and it stops extruding (no space to extrude) then lower is slightly so that the line it is printing is nice and flat, not like a bead.

I don't understand why yours is blobbing like that. Are you using some odd ABS? Looks fluorescent in your photos. Maybe the dye is causing different behaviour.

Share this post


Link to post
Share on other sites

No, I just grab the sleeve that connects the motor to the screw and turn it with my fingers. Once it's adjusted for the first layer, you don't have to touch it after that.

How flat is your glass? Have you put a straight edge on it? The first bit I used was completely bent in every direction. I went and bought some 4mm stuff that was perfectly flat.

Share this post


Link to post
Share on other sites

Thank you, I will try adjusting z-axis for the first layer during print. I think the glass is flat, but I can't level it perfectly. When printing in some places its higher and lower in the others. If the bed is too low, plastic won't touch it in some places, and if the bed is too high the extruder will jam after printing in some areas.

 

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

  • Our picks

    • Taking Advantage of DfAM
      This is a statement that’s often made about AM/3DP. I'll focus on the way DfAM can take advantage of some of the unique capabilities that AM and 3DP have to offer. I personally think that the use of AM/3DP for light-weighting is one of it’s most exciting possibilities and one that could play a key part in the sustainability of design and manufacturing in the future.
        • Like
      • 3 replies
×

Important Information

Welcome to the Ultimaker Community of 3D printing experts. Visit the following links to read more about our Terms of Use or our Privacy Policy. Thank you!