What causes this kind of warping with ABS?

[Merad]

So I tried my first ABS print yesterday, the parts look fantastic except that the bottom 4-5mm of them warped several mm off to one side: http://i.imgur.com/6kJliMF.jpg

I'm using Makergear black ABS filament printing on kapton tape coated with hairspray. Extruder temp 245 bed temp 110. I'm using rsilvers S3D "ABS Ultra quality" profile, I believe the only thing I changed in it was upping the infill to 90% and enabling supports. I also made a cardboard shield to go around the printer on all four sides with a few pieces on the top so that it was probably 50% covered.

[jsc]

ABS will warp and pull off the bed, it's a fact of life. There's a number of solutions. The most hardcore is to enclose your printer to keep it nice and toasty in there during the print. You've made a start on that, but obviously more is required.

It looks like you're printing a filament guide there. I've printed that successfully without a heated enclosure. You may wish to try chemical adhesion measures. Either glue stick (I like the washable purple ones), or a thin layer of ABS glue (a slurry of ABS fragments dissolved in pure acetone) will help. You can try it on the Kapton, or on bare glass.

At some point, when your model becomes large enough, getting the model to stick tightly to the bed will no longer be enough. It will pull so much that you will get delamination cracks between layers, even if the first layer stays attached. At that point you really want an enclosure.

Some further thoughts: I've found that the shape of the model also determines how well it will print in ABS. Long straight runs of filament are bad. Cylindrical layers, or straight runs broken up by indentations are better.

Also, 110 may be too hot, although I haven't done an exhaustive test. Try 100.

[Capt. John]

rsilvers profiles.zip

(11.4 KiB) Downloaded 616 times

RSilver's abs setting gave me my mojo back with abs, hope the above zip opens and is useable.

I checked and it does work and open, 2 settings for abs, used the regular and not the ultra.
110 is what works for me as in the factory rsilvers file. Prints abs as good as stock parts on my M2.

jimc sent me this info and I thank him for it and soon the rest of you will if your abs parts come
out as good as mine.

[willnewton]

Adding a 1/2" brim or skirt with a 0mm offset, depending on your software, may help.

Also, increasing your infill will exacerbate the issue, as it makes the pulling action stronger.

If you are handy with design software, rounding over the sharp corners will help keep them from pulling away as well.

Your large fan should be off.

[jmilkey]

Use Rafts....you will be glad you did.

jmilkey

[Bluesoulx12]

Hey all,
I am currently using a glue stick setup with a ikea box enclosure. I am also using the 50mm fan mod to put it on the back of the stepper drive (pulls the abs). I am getting a fair bit of this cracking. I know this is a large straight part, but is there anything I can do to make sure this prints without these cracks? I am also a bit fearful that the stepper motor will overheat in long prints (>14 hours) so I keep the enclosure slightly open and keep the room at a cool temperature (75 degrees), but it doesn't seem to be enough.

Need someone to come up with a liquid cooler

[jsc]

Are you running that fan during a print? No fan for ABS.

[Capt. John]

There's limitations with ABS. Large parts is something I'm not even going to try.
14 hour prints are beyond my experience and patience level.

Printing with PET+ is more stable, stronger and not sensitive to heat warp-age.

[Bluesoulx12]

I am running that fan (50 mm aimed at stepper) during hte print, but it does get very hot during prints.

Is PET+ the same cost of ABS? I'm printing very large pieces (starts at 8 hour build times, up to 24 hours) and plenty of them (33 pieces in total)

[jimc]

no cost to buy the pet is double that of abs but how much abs have you wasted in failed prints by now. what you are printing there is not going to work with abs. enclosure or not. for an enclosure to work it needs to be up around 70-80c. what you have helps for sure but it wont cure the issues of needing a heated chamber. your options at this point are pla and pet.