Arranging the Print Bed

I’m new with the TAZ 6, so excuse what might be an ignorant question. When you guys print multiple parts in a run, how do you arrange the bed? Do you keep the parts close together or do you use as much of the bed as possible?

Saturday night, I printed 4 parts in ABS. I took no particular care arranging them on the bed (other than getting the side of each I wanted down to be flat on the bed). They came out perfect.

Sunday night, I printed the exact same 4 parts. This time, I thought to myself I can save the printer some needless travel if I bunch the parts close together. This time, two of the parts sort of “drooped”. Not enough to be unusable for my purposes, but not the perfection I saw Saturday. Some of the straight edges aren’t straight, and a few sides are bulging.

Two variables changed. (1)The arrangement of the parts, and (2)the temperature in my shop was warmer Sunday than Saturday. I didn’t measure the temps, but it seemed much warmer. Any educated guesses on which if either might have been the problem?

-Ed

I tend to group objects together to avoid extra travel time. My secondary theory is that this also minimizes the exposure of edges/faces to the thermal differences with the moving bed… and grouping the edges may disturb the airflow inside the cluster.

Objects print primarily in the center of the bed on my printer, but every so often I remember to move projects around the bed. Varying the placement of objects (clusters) will help prevent air bubbles from forming under the PEI… at least that’s the theory. Repetitive removal of objects from the same position on the bed can weaken the adhesive which will eventually begin lifting from fatigue.


None of this is proven, just my own speculation…

As you didn’t have this issue with the objects farther apart, it makes me suspect over-heating. By moving them closer together, you gave less time for the previous layer to cool before the next one is laid down. You can try increasing the fan speed to get better results, but this can lead to lifting and warping when printing with ABS.

If you are in a production type environment, it can be very beneficial to maximize this time and find the perfect balance. (We do this in our cluster) If you are not going to be printing this over and over again, it may be best just to leave them a little further apart. GL!

Thanks kcchen and Brent. I’m not in a production environment!, just a home workshop. I was printing some carraige stops of my own design for my lathe. I needed two sets of two parts…then the next night I decided why not make some extras since it’s so easy, and got the drooping…then yesterday I made another two more sets with the spacing further apart to see if it would help. It did help.

So I originally needed two sets, and now I have 6. I may keep the drooped ones for my own use and put the straight ones on ebay.

Thanks again,

-Ed