Printing tiny ABS part help please !!!

[NBD3D 0]

I am having no success printing tiny parts in ABS.

 

-Ultimaker S7 with material station, firmware 9.0.0, AA 0.4 nozzle, Ultimaker black ABS.

-Ultimaker Cura 5.8.0, normal visual-0.15mm, brim option changed to skirt as there are no plate adherence issues and brim trimming on tiny parts is a royal PIA.

  Also tried slowing down speed to 0.3mm but no success there either.

-At present I am attempting to print them 5 at a time (see attached pic of bed in Cura) before trying to print more in a session.

 

The part is basically a simple spacer about 4mm in size. It is used to keep proper separation between two circuit boards. One each end are conical like nubs for board alignment.

 

Now if I print using Ultimaker tough PLA, it prints fine enough (left part in pic). But with ABS it becomes a steaming pile of smeared crap (right part in pic).

Watching it print ABS it seems like all is does is smear the plastic and cling to the print head.

I'm scratching my head here because the material is from Ultimaker, slicer from Ultimaker, and printer from Ultimaker. I was under the impression this was going to just work. Instead I get the sense that I'm about to embark on the trail of hunt peck and cuss.

 

Any ideas?

[Slashee_the_Cow 519]

ABS is a %*@#! thing to work with. It has the adhesion of a half eaten muffin and if you so much as look in its direction while it's printing, it'll warp. Also the fumes are poisonous. I'm sure UltiMaker make very high quality ABS but that doesn't change that it's still ABS and acts like a spoilt toddler when you try and print it.

 

ABS is a great plastic if you're injection moulding it (a lot of toys are made of it... including Lego, although they have their own secret formula of it) but unless you have a good reason it's more hassle than it's worth to try and print with. Most of those reasons are "able to withstand high temperatures" although I don't even know all the materials the S7 supports (I'm a lowly scrub with a cheap Chinese printer), let alone how they withstand high temperatures. I use PETG in situations where I'm worried about PLA melting, or occasionally TPU (as long as the part is going to be big enough to make it solid).

 

The most common argument people use when promoting ABS over PLA is that it's stronger - it isn't particularly, just less brittle, and tough PLA fixes that anyway.

[NBD3D 0]

Slashee_the_Cow, thanks for the reply. Hehe, I'll definitely try the 'not looking at it while it's printing' approach and see if that helps. ABS in this case is needed because unfortunately PLA won't hold up to in-vehicle temps on a sunny day. BTDT. I'm aware of the ABS off-gassing during printing. The S7 has a fan/filter on it that supposedly deals with that issue. I only see paper for the filter and no charcoal (which is what I'm used to seeing for such type of filters) so I can only hope on that one. I also do not believe it is humidity related because the ABS roll is in the humidity controlled material station. These parts are tiny, around 4mm, so not large enough for warping while printing to become a concern. I purposely put 5 of them on the bed to print sequentially one layer at a time thinking that by the time the next layer began the prior layer had cooled enough. I've played with print volume (50%,60%,70%,80%,90%) just to see but it still winds up pile of smeared crap.

[Slashee_the_Cow 519]

On 1/11/2025 at 7:05 AM, NBD3D said:

These parts are tiny, around 4mm, so not large enough for warping while printing to become a concern.

It works both ways. Too big and the surface is so big that one end doesn't agree with the other. Too small and there just isn't enough to adhere to make sure it stays in place.

 

On 1/11/2025 at 7:05 AM, NBD3D said:

I purposely put 5 of them on the bed to print sequentially one layer at a time thinking that by the time the next layer began the prior layer had cooled enough.

Your intentions are good. However warping largely occurs while things cool so it'd be better* to try doing one at a time.

*”better” isn’t meant to imply I think it will fix your problem. I’d love to be proven wrong, but I still think printing these with ABS is a hopeless cause.

 

On 1/11/2025 at 7:05 AM, NBD3D said:

BTDT. I'm aware of the ABS off-gassing during printing. The S7 has a fan/filter on it that supposedly deals with that issue. I only see paper for the filter and no charcoal (which is what I'm used to seeing for such type of filters) so I can only hope on that one.

Your printer is much fancier than mine 😞 

 

If you're just planning to have it in a car on a hot day, PETG should suffice (its glass transition point - the temperature at which it starts to soften - is around 85°C). @GregValiant printed a tail fin for his car which is in the Florida sun all day out of PETG and it's been fine for a couple of years. For something that small, it's not going to be flexible at all, in case you were worried about that aspect of PETG. And as long as you can get things hot enough (and the S7 definitely can) it's often no harder to print than PLA.

 

Honestly, I'm just not sure printing something this small out of ABS is ever going to work. At an industrial level it would definitely be injection moulded. You could always put on your mad scientist hat and use Cura's "Mold" setting to print a mould out of PLA (I wouldn't recommend tough PLA) and then hold your mould under the nozzle while you get it to manually extrude ABS... but this is "mad scientist" level stuff beyond even what I've tried. And I'm mad enough to create multicolour (at least six colours) prints that are flat on a single extruder machine (may have ruined a nozzle or two during testing).

[gr5 2,280]

Oh!  These are really small.  So small.  Yeah you need to cool the hell out of these.  I'd print like 10 "all at once mode".  I've printed things this small before and it was a pain in the neck to get the settings right.

 

So normally ABS prints with fan at a low speed.  For these tiny parts you probably want 100% fan.  Especially so close to the print bed.  By default cura turns the fan on slowly so it's not till the 5th layer or so that the fan reaches full speed and that is probably like 30% for ABS.  You want to hit 100% on the second layer.  So make sure you find and change that setting.

 

I'd try 100% fan and put them as close together as possible so when printing one part, the fan is blowing on neighboring parts.

 

I'd also experiment with lowering the bed temp a bit.  With ABS you normally want it well above 100C to get parts to stick well and not warp to the bed but for parts this small, warping off the bed won't be a problem.  So I'd try 90C.  This will also save a lot of time heating up as the last 15C takes most of the time.

 

Normally with ABS you don't want the part to cool too much because otherwise you get layer adhesion issues where the currently printing layer isn't melting the layer below and you get horrible layer adhesion but the part my look and feel fine. So after you print a set of parts, break one on purpose to see how weak the layer bonding is.  If it breaks 100% along the layer line and doesn't even skip to the next layer in the break then you did too much cooling.  Ideally the break will cross several layers.

 

You should really use a .25 nozzle if you have one.  3dsolex sells cores with .15 and even .1mm nozzles which I've used and work pretty well but I recommend the AA 0.25 from Ultimaker for this.  I don't think the .25mm nozzle will help your current issue but it will help the quality of the prints in other ways.  But maybe the quality is good enough with the 0.4.

 

I'd also experiment with layer height trying 0.1 and 0.2.  I have no idea which will work better but it seems like 0.1 won't need to cool as much?  But maybe bad layer adhesion if the new layer is only 0.1 thick?  You need to experiment.

 

[gr5 2,280]

This is something I printed years ago.  I printed them all at once.  I used lots of brim. But I used PLA so things will be different.

 

I don't know what nozzle this was.  I have a 0.1 nozzle but this may have been 0.4, I just don't remember.