Calibration Steps?

3d Printing / Slicers / Setup / Problems
1

Hi

I’m new to the group so please forgive my newbie questions!

I am looking for help getting my Greeetech A10s calibrated, since I am having recurring issues with my prints.
Are there any resources that provide a step-by-step approach to this?
A text resource would be particularly nice for efficiency’s sake or, barring that, an ordered listing of videos?

I have been printing parts I design in Freecad for 2 years using dry PLA, PLA+ and TPU with a 0.4mm nozzle.
The A10 beds are convex but by selectively shimming with Alu foil I have 1st layer problems under control.
When I make prints sliced with Cura 4.13 or 5.1 my prints are often porous in the horizontal plane, and weak.
Curiously this happens with 100% infill and the lower the layer height the worse the results.
I have tried increasing the number of walls, tried various other setting to no avail.

Any help or guidance would be greatly appreciated!

-Jay-

2

I actually made a small tool to simplify and to proper calibrations, as on most pages you get told to print calibration cubes, which is bullshit.

The motor steps are steps/mm and when using a cube it is steps/(mm+filament+slicer settings+…).

Here is my simple tool I made to mount calibers to the printer and the text explains how to calculate and set the steps in firmware.

3

Thank you Geit, that looks like a fast way to set up scale ratios without having to print!

I mis-used the term calibration since I I forgot it had a specific meaning in 3D printing, I am looking for a method of optimizing settings like wall thickness, extrusion rates, temperatures etc. so I can generate good prints.

I would like to print objects that have smooth non-porous walls with strength in the Z plane. Even with 100% infill I can often see thru holes in 2 or 3mm ‘solid’ sections. As I reduce layer height from a fast printing 0.03mm to 0.01mm the problem gets worse, so I am looking for a test routine where I can figure out what setting need to be changed.

This problem varys a bit with different filaments but is still present. I made a lens shade using TPU and it was so porous I filled the interspaces with a black weatherstripping adhesive to get an opaque wall.

I appreciate any help with this crazy situation! -Jay-

4

It is the only way to do the calibraiton.

Printing something involves the filament type and the slicer settings.

Both have an impact on the print size, too. so never calibrate the machine against something external.

So first get the hardware calibrated and then the software.

5

Have you any steps you would recommend once the X Y Z scaling is correct?
Thanks for the help.
-Jay-

6

Usually it is just the first layer which has an elephant foot depending on the first layers squish. There are settings for that in all slicers.

The other measurements are just fine. This one you can check with a calibration cube or a hollow box, but it is right in the most cases anyway.

Ah, and do not forget the extruder calibration. It has a huge impact on the overal size of a print as well as on the quality. In most cases a little over extrusion has no effect on the quality and helps closing surfaces, but when it comes to correct sizes they matter.

Latest cura does a better job in filling areas by over extruding on purpose when needed, so a proper extrusion rate is more important than ever.

7

Thanks, since I am troubled by weak verticals I should increase the extrusion rate, thanks for the help!
-Jay-

8

Dialing in your Z Offset is also very important. It may seem like it’s dialed in, but may still not be. I use 30mm 1-layer test squares to check the print quality, to ensure I’m getting even, smooth, accurate lay down of the first layer. I found a video that helped me get started: [U]Best method for 3D printer bed levelling - YouTube.

I first get the Z Offset set so it lays down an smooth, even, solid square. I then measure the thickness. If it is too thick I reduce the Flow Rate; too thin, increase the Flow Rate. As the flow is adjusted, it may affect the smoothness of the square, so the Z Offset may have to be adjusted again. Repeating the process a couple of times gets me a good, strong square that’s the right thickness. From there I can print test towers for stringing, test cubes for more checking of dimensions, plus corner sharpness, bridging ability, wall smoothness, overall strength, and so on.

9

Thanks very much Ender5r! I will try printing some small squares as the video suggests. Using the Ikea mirror for a glass bed is a nice idea. My printers have a concave profile that I have shimmed under their magnetic print surfaces to partially flatten them. Printing on a flatter surface would be a help.

Thanks for the tip on setting flow rate and your method of gaging this parameter, along with subsequent test prints to get other settings under control,

I will give a try this afternoon since I have a part with a thin vertical I need soon.

-Jay-

10

I have successfully used the printing of squares to get the bed level. Took some time to get good results since I found I had a mechanical issue that was compromising the process.
I then designed a piece with a thin vertical and boosted the flow rate to 120%. This is yielding non-porous walls!

I want to thank those who helped me overcome my printing faults.
As a neophyte the video and concrete steps suggested by Ender5r did the trick.
-Jay-