Taz 5 ABS structure not sticking uniformly to plate

My Question/problem description:

Not sure if its an issue with the TAZ 5 (arrived in late December) platform, OR my construct design

240o and 110 o for ABS from LULZBOT Overnight print does have intricate internal structure but that design is synmetrical

Photograph of the overall unit
Detailed photograph showing the area in question

please see attached photograph

Video of any movement related (If possible)
Steps to reproduce

not sure this would be of use


As detailed of a description as possible
See photo
With larger prints I do seem to have trouble sticking uniformly to the platform? this was 120cm X120mm
However this has happened with small 3D prints as well as 50X50mm


This should be a flat square box, but you can see extensive lifting
I though increasing the wall thickness might help and its seems worse


Any suggestions or help would be appreciated.



That’s Lifting due to ABS contraction. There are a number of things you can do to minimize it. First print with a 5MM Brim layer around the perimeter. That should prevent some corner lifting. If it persists, and seems to be more prevalent on one particular corner, you may need to adjust that corner. You want a 0.40 or 0.45mm thick starting layer. If the corner is too close, you get a really thin smeared layer that looks like it should stick really well, but it lifts due to heat contraction. if you are too far away, you don’t get good adhesion and the part lifts. Running the bedcalib gcode file that came with the sd card in the printer multiple times until you have a perfect contact pattern is not a waste of time.

If you are printing in a non heated space, like a garage or something similar, you will need to construct an enclosure around the printer to prevent lifting or splitting. A temporary one can be made out of turkey roasting bags and tape if you want to try it out first. Make sure the electronics control box cool air intake vent ends up on the outside of the enclosure.

You can increase your odds of success by also printing a “skirt” in addition to a Brim layer. A skirt is a sacrificial 1 extrusion wide container that the printer builds around the outside of your printer, which acts as a thermal insulator. It uses a lot of plastic, but it works.

White ABS also tends to have weird printing properties. Depending on what they used as the dye, you may need to go higher or lower than normal temperatures to get good layer adhesion. I’d start with 245 or even 250 and see if the adhesion seems to be better without any scorching or deformation. 110 for the bed should be more than enough.

Large Square boxes need Mouse Ears.

They work great. I created a collection of them of various sizes and thicknesses and attach them to my corners either in Slic3r or when I’m designing the part.

Do a google search for 3d printing mouse ears. Lots of good information.

That being said, you’ve got some pretty severe lifting on the left corner that probably even ears won’t fix, so something else is going on there in addition to normal ABS warping.

Kenny

Thanks for the suggestions and I really appreciate your help and time spent.

Yes the print finished a few minutes ago and I was quite disappointed. It was a 12 hour print.

Done in a 72F room (not a garage).

It looks like the ABS warped and burned ? (see picture)

I did use a non contact temp probe and the platform was about the 110o near the print but cooler 85o away from the print

I am about to add the 5mm edge (to a smaller model) to see if that helps.

note the color turning from gray and looking more brown than it should.

Again appreciate any suggestions…

You are going to want a thicker bottom layer, and probably drop the bed temperature a bit. The edges definitly lifted, and from the initial contact pattern at least one of your corners is off on the low side. Also, an Aluminum bed plate helps immensly with heat spread, but thats a bit more modification than most people want to tackle.

So my Taz5 does have a heated bed, but I think you are suggesting adding an aluminum plate on top of the standard platform? Heat would then transfer from the glass(?) bed and spread over the aluminum? Ill look to see if I can find such a modification. I assume you have to glue down the plate in some way ( and how you do that must be critical).

thanks
Mitchell

The aluminum bed modification replaces the glass with a 3/16" thick 12" x 12" aluminum plate. You stick the PEI sheet on top, heater on the bottom, replace the corner pieces with once with slightly more recess, and there you go. Spreads even heat further out to the edges.

All the above recommendations are great… 5mm brim, 1cm skirt, using anchors. The other thing I’d recommend is turning off the cooling fan for the first 3-4mm of the project. And to keep cooling to a minimum for ABS… 40-60% is a good range. The fan should only be turned on 100% to help bridging.

Looking at your follow-up picture, the bed was left at 110C too long and it scorched the bottom. Drop the bed temp to 100C after a few layers. The bed only needs to be at 110C for the first few layers to help with adhesion… the ABS is still malleable at 110C, so it will be more susceptible to warping / lifting when the upper layers contract from cooling.

Is that your design? If so, rounding the corners may reduce the likelihood of warping… I’m not sure why, but it helps my projects. Could be the curved surface helps the airflow… curved surface creates a laminate airflow versus edges which cause turbulence.

Last tip to help mitigate warping. Make sure you have the proper nozzle height set (from the picture of the bottom, your first layer looks good), then to help adhesion use the Z-offset Gcode setting in the slicer software to lower the nozzle slightly. Use .1 to .25 offset value.

I keep my fan off for abs printing except for bridging or very small layers.

The aluminum plate is a modification. You spent $2200 for a printer that will print ABS fine, for large prints you need an enclosure warm room or otherwise, even in the summer. No fan with ABS. If you want no issues with ABS do some searching on here or better yet switch over to PETG and your problems will go away. Yes I know you have some ABS left on that roll, save it for small jobs.
Added, the aluminum plate is a good idea, don’t know why Lulzbot does not go that route instead of they use.