Poor layer adhesion and some funky y-axis stuff on TAZ

I’m using LulzBot white ABS plastic, printing at 230C, bed at 65C. 0.35mm layer height, two wall thickness.

I’m having some pretty poor layer-to-layer adhesion with many, many, MANY gaps visible. I also had some funky stuff going on with the y-axis. The print layers seemed to keep shifting over the higher up the print got.


I have read somewhere that upping the print temperature helps with layer adhesion (go to 240 maybe) But I have not tried it myself.

also adding a protective skirt around the model, that goes all the way up is another trick that has been mentioned.


Not sure about the Y…but perhaps it is moving too quickly and losing steps. I turned the max speed down to un-skippable levels in my firmware.

Ok, I’ll try upping the temp. What is the max speed you have your y-axis set to? How did you go about setting it in the firmware? That’s something I’ve never done before.

Thanks!

How was your 20mm test cube print?

I would not set the temperature to 240C. That temp is high enough to potentially damage the PEEK insulator in the hot end. It may cause the hot end to fail. The splitting you are seeing is more than likely due to the ABS cooling, warping slightly and then splitting apart. The suggestion on using a tall skirt would be the most helpful option. The suggestion to slow the print down a bit will help as well.

The specs on the lulzbot website claims 240 is the max temp…http://www.lulzbot.com/?q=products/budaschnozzle-20-w-035mm-nozzle “Do not go above 240C or you risk damaging your hot end”

Are you saying that is not true, and should be lower?

I also noticed the firmware’s max temp is set to 250…

Just a note on your layer height. I wouldn’t suggest a layer height that is the same size or larger than your nozzle. I think something like 0.30 layer height would help you “squish” the layers together a bit more. As it is now, you’re trying to lay lines of filament on each other with no squish at all really.

240 is a bit hot for our ABS filament. I’m very cautious when approaching the upper limits of the hot end. Keep in mind that the heater may overshoot the set temperature as it settles in to the desired temp. PEEK starts getting soft around 245C. I always recommend raising the temperature in small 1 degree increments rather than large temperature jumps. It may take a little bit longer, but a conservative, measured approach has served me well. I’ve seen too many friends kill their hot end and other things by pushing things unnecessarily.

Ya, what marsao said above: I didn’t notice that, but your layer height is the same as your nozzle. I’d suggest trying it with a lower layer height too, now that I see that.

see here: https://forum.lulzbot.com/t/left-z-axis-motor-spins-the-down-at-the-beginning-of-a-print/115/1 and the other posts in that thread.

How did you go about setting it in the firmware? That’s something I’ve never done before.