10
$\begingroup$

I'm printing cylindrical pins for a spool holder, but all my pins have irregularities on the external surface of the cylinders (see photo for partially printed pin with irregularities).

It's hard to tell for sure, but it appears that the hot end will occasionally move a piece of soft plastic it previously laid down.

I've tried decreasing print speed, travel speed, and layer height but I still get the irregularities.

What parameters are most likely to effect cylinder regularity?

Cylinder Irregularities

$\endgroup$
  • 1
    $\begingroup$ Could be moisture in the filament, overextrusion, partially clogged hotend, too high extruder and/or bed temp or a combination of these. $\endgroup$ – Leo Ervin Feb 7 '16 at 0:45
  • $\begingroup$ Thanks Leo. I'm a 3d printing n00b. I hadn't even considered any of those things. $\endgroup$ – Doug Richardson Feb 7 '16 at 2:43
  • $\begingroup$ You should make that an answer instead of a comment so I can vote it up and accept it. $\endgroup$ – Doug Richardson Feb 7 '16 at 2:43
  • 1
    $\begingroup$ Looks like wicked over-extrusion to me. $\endgroup$ – Ryan Carlyle Feb 7 '16 at 4:50
  • 1
    $\begingroup$ I'm not sure though. Could be other things as well. Like it could be a thermistor malfunction which causes reading fluctuations which causes overextrusion only in some parts, or could be a partial clog cuasing it, or something else. $\endgroup$ – Leo Ervin Feb 7 '16 at 7:45
4
$\begingroup$

This is probably a result of bad quality filament. If you haven't changed much in your setups, haven't changed slicers, but may have changed spools, then this might be the result. I would try using another spool and perhaps switch suppliers. I know it's expensive and there seems to be a stigma around it, but MakerBot Industries provides quality PLA (some ABS also).

Other than that, you've done some of what I would suggest in this case which are the following:

  • Speeds
  • Layer height

My only other suggestions would be:

  • Check how level your build plate is
  • Check material requirements. ie ABS is ideal between 230-240C according to MSDS with about 110C build plate temp, PLA between 210-230C. Sometimes too hot of a hotend can result in overextrusion or ooze.
  • If the cylinder is smaller, try changing your slicing settings to have a time minimum for each layer. In my experience, a material like ABS will begin to flare out with variations in the print environment. When the material flares out, as the nozzle comes across the area again, the flared areas will be pushed aside. If you adjust your slicing settings to about 15 seconds (refer to this calculator), then the material will have time to cool slightly from its plastic state. You can cheat this slightly by adding another object somewhere further on the plate with the same height, since the time it takes to rapid to the area and print the layer might be enough time for cooling.

I would also recommend doing some in depth maintenance to eliminate in obvious problems (such as cleaning your nozzle, rods, belts, etc.)

$\endgroup$
  • $\begingroup$ Quality of filament != how much moisture it has absorbed. Any quality filament can abosrb moisture... $\endgroup$ – Leo Ervin Feb 8 '16 at 17:39
  • 1
    $\begingroup$ You're right, (quality of filament) != (amount of moisture absorbed) directly. However, (amount of moisture absorbed) is a contributing variable to the (quality of filament). If you're a machine shop and buy your steel from a boat yard, that means you're probably using bad quality material and thusly need to find a better supplier. You, as the manufacturer can inhibit bad quality in your materials as well by storing/handling them improperly. I'll update my answer later to include more things to look out for or some proper storing/handling techniques. $\endgroup$ – tbm0115 Feb 8 '16 at 17:48
  • $\begingroup$ Indirectly as well. I'll be perfectly honest with you: that's an unrealistic analogy, and I believe so is this. So if my food is rotten what's the probability that it's me storing it improperly rather than the company which produces it? I don't think it's a 50/50... $\endgroup$ – Leo Ervin Feb 8 '16 at 17:59
  • $\begingroup$ My response was unrealistic to simplify my point. Also, I am not inferring any probability, there are no statistics in my responses. I'm merely stating possible problems and any potential solutions I have for those problems stated. I'm editing my answer to remove my reference towards your comment to avoid any further confusion that I'm directly relating moisture to the OP's issue. $\endgroup$ – tbm0115 Feb 8 '16 at 18:07
  • $\begingroup$ Well an unrealistic analogy doesn't help prove anything. I really don't see where you're going with this. If you've removed the part of the moisture being the problem your answer is based on a premise that the OP has changed spools which he hasn't mentioned he has. Also, what do you mean when you say "Speeds" and "layer height" as possible issues. $\endgroup$ – Leo Ervin Feb 8 '16 at 18:16

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.