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ABS printing settings

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Posted · ABS printing settings

Spend some time getting the bed level. First you need to know if your glass is flat. Just use a ruler or something to see if is or not. If not, then you'll never get a good print over a large area like that.

Have a level bed is essential in getting a good first layer. If the bed is too low then the ABS will blob and the head will push it around. That looks like what has happened in your print.

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Posted · ABS printing settings

If your bed isn't flat you can compensate in several ways. One is to use a thicker bottom layer. This is fine for most things. Another trick is to use the "raft" setting. But this will make the bottom layer look pretty bad and is even more likely to look bad on an ipad case (but for most things it doesn't matter). You could also choose either of these settings and print the ipad case sideways.

Personally for an ipad case, I think .2mm layers would look better.

 

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Posted · ABS printing settings

Another one suffering for ABS printing noob-ice

I'm just printing normal boxes, bellow you can see two separated attempts.

I've tried bed temps from 70-130 extrusion from 240-255 diferent flow settings, turned off the fan, and nothing seems to work.

This last complete print, is perfect on the higher layers but the bottom ones are incredibly strange as you may see.

https://www.dropbox.com/sh/erzwmmnmc4mjmoi/B4aK5dbJJP

 

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Posted · ABS printing settings

It looks like it doesn't like that overhang at all.

And there's some major warping going on on your first layer.

That raft is huge. By the time the print head has finished with it, it'll have changed temperatures several times if you're using a heated bed. Have you tried printing directly onto the kapton tape with ABS glue and no bed heating at all?

What is your head speed? What results do you get if you use my settings?

Can you post your printing parameters?

 

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Posted · ABS printing settings

So the print is perfect until the first overhang. Any idea?

 

Now keep the fan

With ABS it's a balance between using enough heat to get layers to stick to each other and enough fan to make good overhangs and top skins without cooling too much to stop the layers from sticking to each other.

I managed this bit OK on small prints but not on large prints.

Good luck fns720 and keep us posted :)

 

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Posted · ABS printing settings

After several months of fighting with ABS on Ultimaker original I think I found another source of the ABS layer bonding problem. I started to print couple of really small objects - the "needles" on this picture are ~5.5 mm thick, the length of the objects are ~25 mm:Ultimaker-ABS-layer-bonding-sample.JPG

If I printed a single one with my usual settings, the entire object is strong and I almost couldn't break the needle from it by hand (item 2). But as soon as I start printing multiple of them the needles become too weak - some of them can break during the removal from the heated bed (item 1).

This time, due to the shape of this object, the only difference between the two prints was the usage of the retraction. For a single object there's no need to retract the plastic but in case of multiple objects the printer retracts a lot. Interestingly this retraction weakens the objects at the needles only - the wider bottom parts are still strong enough although they are ~12 mm wide and they have an M8 thread in their bottom.

Do you have any experience with recommended ABS retraction settings? I don't want to switch it off completely because the result will be a stringy mess.

 

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Posted · ABS printing settings

I never have good results with retraction. I prefer cleaning up the mess afterwards or it tends to under or over-extrude at critical points.

Another source of your problem could be that with multiple needles, the layers have much longer to cool down between successive writes. Maybe you could try enclosing and heating the inside of the ultimaker to prevent layer temps dropping too much.

 

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Posted · ABS printing settings

with multiple needles, the layers have much longer to cool down

 

I think it's that. Printing a bit hotter might help. But really a heated bed helps much more. And enclosing the machine (or at least the sides).

 

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Posted · ABS printing settings

I use different settings for printing ABS. I actually never change the temperatures.

- 260°C extrusion and 90°C bed

- ABS/Acetone for adhesion to the glass plate

- the first 5 layers (~0,5mm) fan off, then linearly increase the fan speed to 100% (~1mm)

This works for me for print speeds of 20-75mm/s and layer heigths of 0,02 to 0,1 mm. I have good layer bonding (watertight structures) because of the high extrusion temperature.

 

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Posted · ABS printing settings

I've never had issues with ABS, even with objects as large as 250mm or as small as 12mm at the base, and up to 250mm tall, with two different reprap printers. The method:

- glass bed - heat to 100C and keep it there,

- glue stick for adhesion - forget ABS juice/tape/hairspray, and all that messy stuff - when the print cools, it will literally pop off the plate with glue stick, but it will stick firmly while printing - I've never seen any need for a raft

- print temps from 236-244C - I generally use Ultimachine or Protoparadigm ABS - any hotter and it is subject to stringing and other artifacts

- room temps around 80-82F - the printer keeps my small room warm - keep drafts off the print, but no special treatment or enclosure

- for parts with overhangs, I use the fan at low to moderate speed after the first few layers to "freeze" the plastic immediately after extrusion and prevent curling upward - thinner layers work better for this - I never use supports, and almost never have issues with the overhangs up to 50-degrees or so

 

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Posted · ABS printing settings

I had serious issues in printing Ultimaker White ABS. First I could not get it to stick and then I would get either delamination, loss of adhesion or blobbing and malformed prints. Here is what I ended up with, which produces acceptable results:

- a very thin layer of UHU glue stick directly to the aluminium while the bed is cold

- heated aluminium bed at 100 C

- printing temperature 235 C

- printing speed 50 mm/s

- fan on full (default settings for fan) (!)

When I did not enable the fan, I will get strong upwards curling of any sharp corners. Using the fan seems to overcome this problem!

PS. I also had to go with 40 % infill or I will get severe molewarting (pillowing) of the top surface with gaping open holes and upwards curled edges.

 

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