Dimensional accuracy help on a delta?

(Nathaniel Stenzel) #1

The inner and outer diameters of a calibration print are both coming out a little too small while the came out a little high. It was sliced on Cura 3.6. Is it the printer or the slicer or maybe the slicer settings.

(Nathaniel Stenzel) #2

It seems the Monoprice Mini Delta printer has the wrong number in the firmware for the X,Y,Z,E steps/mm. I corrected them and I will be doing a test print now.

(Nathaniel Stenzel) #3

The new step/mm numbers do not seem to be right either, but they are closer.

(Nathaniel Stenzel) #4

The new steps/mm were from an end user wiki page. I think they compensated in the wrong way. I think it is other pieces of math that have the wrong numbers. Are the steps/mm for X,Y,Z the dimensions or the rods?
I swear naming towers after dimensions is the dumbest shit on earth. A,B,C if towers is a much better way to put it.

(Nathaniel Stenzel) #5

This seems to have my answer. It suggests the arm lengths are wrong.

(Nathaniel Stenzel) #6

G33 to check and M665 to set delta configuration parameters. That will hopefully work with my printer

(Nathaniel Stenzel) #7

G33 does not work. M503 does.
“M665 L120.80 R61.70” is reported. 120.8 and 61.7 is what someone was claiming was the specs. That matches.
My steps/mm needs to be set for an accurate height according to one person. Mine are too much, so I will probably be changing the value to less than the original to get the right height. After that, I will adjust the delta arm lengths.

(Nathaniel Stenzel) #8

Careful examination shows that there are 3 hex screws at the top of the towers for adjusting the belt tension of the Monoprice Mini Delta. Now I have a proper pitch on all 3 towers.

(Nathaniel Stenzel) #9

More steps/mm means higher. My thinking was a bit backwards. (facepalm)

(Nathaniel Stenzel) #10

I pushed the limits and did 100mm diameter x 100mm tall and I got within 1% accuracy on the dimensions. The center is either a little high or a little low. The width is perhaps a little narrow while the height is perhaps a little high. At this rate, I do not think it would benefit me much to try to correct things further. I just did an M666 to adjust one tower by -0.3. I guess the measurements are pretty good and whatever off I am may be slop in either the printer, my measuring skills or my calipers. (shrugs)