wijanes
Posts: 2
Joined: Wed Jun 08, 2016 4:01 pm

ABS Cooling Causing Prints to Detach(?)

I am trying to print a rather detailed model of bones in ABS on a Flashforge Creator Pro, using Simplify3D v 3.1.0.

As the print progresses, the edges curl dramatically. Eventually the print head catches these edges, ripping components from their supports. This typically occurs within the first 11% of the print. (I have not bothered to determine the exact layer(s) at which the components catch.) The edges are not curling on the heated bed; indeed they stick rather nicely.

I have read the quick start guide and the Print Quality Troubleshooting Guide.

I have considered that the ABS may be cooling too quickly, causing the edges to curl before the next layer can be deposited. To that end, I printed several test cubes at different temperatures around 230º in 5º increments. I see no discernible difference in the output. The result is always a wide base with sides that narrow toward the middle and widen at the top. The corners curl up, giving edge lines a rounded appearance.
Test Cube
Test Cube
I also considered that the acceleration setting on the printer may be to blame. I turned off acceleration and printed another test cube. The speed was clearly more consistent, but the end product was no different.

Am I right in thinking that the problem here is due to the ABS cooling too quickly? Whether yes or no, does anyone have suggestions for how I might solve this?

I attempted to attach the factory file for the bone model, but it is too large to upload here. It can be downloaded from my dropbox at: https://www.dropbox.com/s/5isxukrwmlyug ... ctory?dl=0.

Thank you in advance for any help.
CompoundCarl
Posts: 2005
Joined: Wed Aug 05, 2015 7:23 am

Re: ABS Cooling Causing Prints to Detach(?)

I would actually say the opposite. I think you need MORE cooling. If it doesn't cool fast enough, it can curl and deform before it finally solidifies. So I think more cooling would help those perimeters stay put.
dorsai3d
Posts: 237
Joined: Mon Jan 11, 2016 9:01 am

Re: ABS Cooling Causing Prints to Detach(?)

I would also like to interject that this is one main reason that ABS has fallen out of favor with many people - it does warp from thermal expansion very badly, which causes all sorts of issues like this, as well as trouble keeping it stuck to the bed. Also, cooling it like Carl suggests can cause issues with layer delamination in ABS, but not other materials.

I've actually got several kilograms of ABS sitting around that aren't likely to get use for much of anything ever because things like PLA and PET are so much nicer to print with.
pbmax
Posts: 34
Joined: Tue Feb 03, 2015 11:19 am

Re: ABS Cooling Causing Prints to Detach(?)

dorsai3d wrote: I've actually got several kilograms of ABS sitting around that aren't likely to get use for much of anything ever because things like PLA and PET are so much nicer to print with.
Agreed! I've given up on ABS all together in favor of PETG. It's a bit oozy and it's not as temperature safe as ABS (85C vs 100C), but it's stronger, doesn't stink when printing, and is hydrophobic to boot (doesn't get soggy over time like PLA and ABS do). Plus it warps even less than PLA so that you can even print it on unheated beds (I use a raft and glue stick for unheated bed prints).
razster
Posts: 54
Joined: Wed Aug 05, 2015 4:48 pm

Re: ABS Cooling Causing Prints to Detach(?)

It's hard to solve this completely for ABS prints unless you have some kind of heated enclosure which stays at the same temperature the whole time
tpete61
Posts: 13
Joined: Sat Apr 04, 2015 12:04 pm

Re: ABS Cooling Causing Prints to Detach(?)

I've seen the same problem with ABS and solved it. Can't remember exactly everything I did though. A couple of points.

Are you using a cooling fan, if so don't at all.
Are you holding the 230 temperature for all layers, this should not change.
Lastly slow your printer down, your assumption of turning the corner into a rounded corner due to printing to fast could be correct.
wijanes
Posts: 2
Joined: Wed Jun 08, 2016 4:01 pm

Re: ABS Cooling Causing Prints to Detach(?)

Thanks all for the input.

The idea of increasing cooling had not occurred to me. Does the rate of cooling influence the amount of warping?

Regarding the suggestion of a heated enclosure: this is my next step. The ambient room temperature is cool (below 21c/70f). I'm in a basement and have little control over the temperature. I could move the printer to an egress window well, where the temperature will approach 26c/80f.

I switched to PLA briefly (with appropriate adjustments to temperatures & cooling) but it was a disaster. Perhaps I got a bad batch (Hatchbox), but 50-100% of my prints jammed. The filament felt uneven to the touch.

(FWIW: I have successfully printed this model in both ABS and PLA in the past using Makerbot Desktop. I've had no successful prints since reverting to ABS or subsequently switching to Simplify3D.)
KC_703
Posts: 238
Joined: Tue Aug 26, 2014 5:23 pm

Re: ABS Cooling Causing Prints to Detach(?)

Can you describe the print bed? Glass, tape, ABS juice...

ABS typically does not like cooling. Start with the fan off. Many people leave the fan off, but a little cooling (60% max) 3-5mm into the print will help... it's really dependent on your extrusion temp. A slightly higher temp will help layer to layer bonding reducing the chance of delamination on tall prints. The higher temp could cause problems with maintaining shape (ie screw holes).

Heating the bed to a higher temp may help the ABS adhere to the bed better.

A brim (5-10mm) will help "seal" the edges so cooler air doesn't seep under the print.

Try a little negative Z-offset to enhance the "squash" of the initial layer. Use increments of -.1, too much and the base of prints may be slighlty wider then designed.


I'd recommend a PEI sheet for PLA and ABS. At a bed temp of 100C, ABS sticks great. Buildtak and Printinz also makes products to enhance ABS adhesion to bed.
greybeard
Posts: 178
Joined: Mon Mar 02, 2015 1:23 pm

Re: ABS Cooling Causing Prints to Detach(?)

ABS is hydroscopic (and depending on various factors, can add to warping and variations in printability)

Look on the box of filament - the manufacturer will provide a Temperature range. As an example, attached shows two brands (Shaxon and eSun) - note their recommended temperature ranges. My machine prints only ABS and I’ve used a dozen different filament brands and each needed some parameter tweaking to get the results I wanted. Not all coffees are equal… I print ABS at 250 to 260.

Keep the part hot/warm and let it cool slowly (otherwise, it will stress relieve itself non-uniformly and too quickly). Enclose it if you can.

Have a good part design with proper features for the material you use (wall thickness, draft, etc).

Adhesion to the heated bed - experiment with location on bed (asymmetric heating occurs).

Differences in bonding material - I used them all and more consistently than others, the qlue stick in attached has become so reliable for ‘me’ and the DaVinci, that I tossed out everything else (sticks, ABS juice, tape, kapton film…)

Attached shows two items of similar size to your photo - they printed well (part on right has a lid glued on). Also attached is a model to try if you think it may be your part...
Attachments
PIR_Tiny1.STL
Solid Model to try
(24.89 KiB) Downloaded 305 times
Filament Temps example
Filament Temps example
boxes & glue
boxes & glue
3D Print Parts
https://www.thingiverse.com/Still_Breathing/designs

Return to “Troubleshooting and Bug Reports”