Prints Not Quite so Good

[teoman]

I am having some issues with printing lately.

Hollow calibration cube of 40mm x 40mm turned out very nice.

On more complex parts, it looks as if the circles and square like features are hand drawn. Some solid layers do not reach the perimeter and there are some shifts that propagate to the outside "shell" depending on layers inside the print.

I discovered that the motors were loose. Fixed that but it did not improve the problem.
Belts look to be tight.
The cheapskates are on tightly enough.

Same results with matter control and S3D.

So I am a bit puzzled here.

[bvandiepenbos]

Possibly one or more of your arm joints are binding.

[mvansomeren]

possibly one of the stepper motors are loose?

[teoman]

Yes. One was loose, tightened it but no joy.

[Nylocke]

Check your belts, pulleys, cheapskates, Ujoints, anything that moves. If you have the metal joints there's a possibility that they could be binding. You seem to be getting the extreme side of delta arm blues. Do you have the aluminum u-joints? There is a good chance they could be binding, it happens quite often.

[Glacian22]

Try lowering the flow rate, it looks like you might be over extruding.

[teoman]

I have checked everything except the universal joints.

Will check those next.

[teoman]

Oh dear...

My u joints were all a bit crunchy and one was even completely seized.

2 hours polishing each rod with metal polish and then the insides of the aluminium pieces with a toothpick an then putting engine oil on the shafts made the movements much smoother.

I often check the end effector movement. But maybe i check it too often as MY calibration has also shifted with time.


Fired up a print. I shall see tomorrow how it turna out.

[Nylocke]

I would advise scrapping the aluminum joints and getting the acetal ones they now sell. Only $10 (though you are in Europe?). Or better yet, go the carbon fiber+Traxas ball end route. You won't regret it for a second. The TrickLasers work great, but you can also get the 288mm ones from TriDPrinting.

[Captain Starfish]

Tricklaser look like captive balls rather than the magnetic ones, is that right?

[Nylocke]

Yeah, TL uses the Traxas ball ends. No risk of popping off during a print and (for our purposes) there really isn't a difference in print quality (magnetic offers slightly less play).

[Captain Starfish]

Is there a quick(ish) release mechanism on one end or the other, if the platform needs to be removed? Being able to pop the platform off to do easier work on the hot-end etc has proven quite useful on the standard arms.

[Nylocke]

If you go with JFettig's platform/carriage design its pretty easy to take the hotend off (relatively). Undo 6 screws holding things in and it comes right off. Or you could design an alternate mount (similar to this really cool magnetic one I saw a while back) and get similar quick switch capabilities.