Geometry vs. degree of success.  I'm noticintg something about my printer...IF the object is

Geometry vs. degree of success.

I’m noticintg something about my printer…IF the object is a Vase…no problem - print finishes.

If it’s shaped like the Make Robot…likewise.

If it’s shaped like a Skill, a Zombiekiller, or a big flat object, the odds of it failing are greater.

I ponder why this might be the case. Some of the smaller objects certainly have a lot of motor movement, but it’s less sustained. I’ve cooled the motors and left them alone - neither makes much difference.

I then look up at the Pololus and wonder if sustained movements might be overwhelming them…kinda like a capacitor not being sized right in a stereo. Could there be a duty-cycle issue with larger layers that’s causing the problem? Long distance movements where the driveris asked to move the effector over a long distance…and poops out before it gets there, could account for the layer offset issues I’ve been having.

Your post was not very clear on what your actual problem is. Your prints are failing because you do not get full movement on larger parts? If you are not getting full motor movement are your drivers overheating? Usually a heatsink and natural convection are enough to cool drivers when the linear motion components are well tuned and aligned. If not then you end up running higher currents and running your drivers hotter. The drivers auto shut down when the temp hits a limit. They generally cool below the threshold quickly and turn back on.

If an axis is not moving but the motors are in fact trying to drive it then you have some friction/binding, or maybe not enough stepper current. I know that’s a little contradictory to what I just said but there is a minimum amount of current it takes to propel even a frictionless/unbound mass.

@Ben_Malcheski This is what I’m seeing: https://plus.google.com/100827274652904341735/posts/D9qvLLAhaXM . I’ve got a spare driver that I’ll swap into the Y Axis and add a little cooling to the drivers and see what’s up.

Oh you have a delta. What I said still holds true but I was picturing a cartesian bot so I was very confused. I think what I said is the details of what @ThantiK meant by weak y axis.

Yeah, I think we’re all on the same page. I’m reaching the point in development where the bugs take a few hours to emerge.