poor binding layer to layer with ABS

I feel like I didnt used to have this issue, but started to have this problem with the ABS print not always binding well layer to layer. This results in very week joints or even mid part breaks - two pics showing a recent print where one layer disconnects very easily from the next.
I am using I think the standard profile for my IC3D ABS but with support turned on.
I have a min with an aerostruder.

Im not sure if there is a way to capture the whole profile I can include it if there is , but it is the default with cura LE 3.2.32

adding the pics which were meant to be part of the initial post

second one

I printed a couple smaller prints which came out good, and then attempted this large piece again. It worked better, but still had a couple places where the binding failed. It also had near the top lots of bubbling.

I thought maybe it had to do with this circular shape, but I recalled that in the past I printed a snip out of this circular shape, and it worked great (see photo)

So it seems like something about this large print gets the printer into some very grumpy state - so confused…

Are you using an enclosure for the printer? ABS is very sensitive to temperature, and requires a very warm (hot even) air temp around the part in order to avoid the layer-adhesion problems like you’re encountering. Drafts can also adversely affect the printing - so the best solution is an enclosure of some sort. (I used an enclosure made from cardboard, duct tape, and a bit of plastic while I waited for my PrintedSolid enclosure to arrive - worked pretty well, although it was certainly ugly!)

Another consideration is extrusion temperature – you can try increasing the hot-end temperature 5 degrees or so to see if it makes things better.

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ya - so I started to wonder about that and for some recent prints I have placed a large box over it - but that seemed to help with the adheasion - which was great - but maybe added to this rough and bubbling stuff.

On this more recent print I used a blanket of sorts to try to help contain some of the heat. Im pretty confused about having both problems - adhesion and also the rough and strange bubbling

I think maybe I should go back and try the pint of just the cm or so of that central circle - maybe there is something about doing the big print - like maybe it works well for a little while and then gets bad.

It looks like its not extruding enough filament. It could be that the filament is bound or slipping in the extruder/mechanism.

Try these:

  • make sure the filament spool is not binding
  • spot check the filament for correct diameter - could cause binding in the extruder path
  • clean the hobbed bolt/gear - not enough bite on the filament could cause slipping
  • tighten the idler by a few turns -
  • check for cracks on the extruder gears and tighten the grub screws… the small herringbone is usually the culprit.

hmm - ok now thats interesting - one one of the recent prints the print stopped mid way, but actually the printer apparently tried to do the whole thing, but the filament wasnt moving anymore. I found it wasnt feeding, and I corrected by re-feeding it and also by tightening (turning to left) that adjustment knob - so I was sort of on that path, but I sure didnt do all the things you are mentioning - Ill have to learn more about all those components in the extruder feeder assembly.

This line, combined with your photo of it getting “bubbly” towards the top looks like a Z axis issue to my eyes. Essentially your Z axis is not moving up properly, causing extra extrusion which creates the bubbles. As it doesn’t start happening until higher up, there will be two things you want to check.

1.) Check that your electronics case fan is plugged in, clean, and running properly. If this has an issue it will cause your Z stepper driver to over heat, causing missed steps. (The Z axis driver shows signs first as it controls two motors.)

2.) Be sure that your X axis is leveled, if this is off kilter than it can cause binding. A good guide on it is here: https://ohai.lulzbot.com/project/leveling-x-axis/maintenance-repairs/

Just a couple things to try, and remember our support staff is available 7 days a week at support@lulzbot.com or 1-970-377-1111

Brent - you are my hero of the weekend - I hadnt checked back on this thread for a while and was feeling really bummed that my printer was printing so poorly as I had really ramped up how many different projects I was trying to use it for. I tried what you said. The calibration was a tiny bit off I think, but the real key was the fan I think. I had had the cover off recently as I had an issue with the wires for the thermistor - and apparently I forgot to re-attach the fan. I ran my print which had failed multiple times with the fan running and the cover ajar and the print worked well again!
I will say that if those parts or that sensitive to temp we might want to improve airflow - there is a big bunch of wires over those drivers blocking the air from the fan, and also Im not really sure where the air is meant to be coming from to get pulled out by the fan (or the other way around) - but regardless - thank you very much for guessing right about my issue - huge help!

Glad to hear you are up and running! The case fan will pull air from the front bottom of your electronics case, pull it over the board, and expel the hot air out of the top rear of the case. We run these printers in cabinets in our cluster room, where the temp gets to ~95f. We have found over heating issues occur when get much higher than 100f-105f when using the stock cooling fan and set up.

There have been a few users out there design some very intricate heated enclosures by keeping the electronics case out of the heated area, and can achieve much higher results. NASA was even able to modify these to print by following a similar process: https://www.lulzbot.com/learn/NASA-high-temperature-printing