# Layer height as an integral number of Z steps

Posted by frankvdh
 Layer height as an integral number of Z steps April 27, 2022 08:15PM Registered: 9 years ago Posts: 978
Hi,
Not really a reprap question, but I'm not sure where else to ask...

I'm trying to get the absolute best possible quality print for a project on my Creality HALOT ONE resin printer. It occurs to me that (as with XYZ FDM printers) it would be better to set the layer height as a value that equates to an integral number of steps of the Z stepper motor. e.g. if Z steps are 880/mm (1 step = 1/880mm = 0.0011363mm) , it would be better to set a layer height of .010227mm (9 steps) or .00909mm (8 steps) than .01mm which would result in rounding each layer to either 8 or 9 steps.

Is this worth pursuing? Or will the difference be undetectable?

If it is going to make a difference, does anyone here know what the Creality HALOT ONE Z steps/mm is?

Frank
 Re: Layer height as an integral number of Z steps April 27, 2022 09:42PM Registered: 11 years ago Posts: 5,785
Yes, it is generally best to set the layer thickness to an integer multiple of the full step movement. It is also best to design parts so that features like horizontal steps that occur at different Z heights are a multiple of the layer thickness.

My printer has a full step Z resolution of 20 um, so I use multiples of 20 um to set layer thickness. That means I can have 0.1 mm layers, or 0.2 mm layers, or any other multiple of 0.02 mm but I don't use 0.15 mm layers. When I design objects in CAD, I plan the layer thickness that I will print (often 0.2 mm) and then design parts so that top layers will land on 0.2 mm multiples.

The reason is that the absolute accuracy of microstepped positions is not very good, but the precision of full steps is good because the driver transistors are supplying the same current at each specific microstep position. The 4th microstep will have the same current at each full step and the 5th microstep will have the same current at each full step, but you can't expect the 4th and 5th microsteps positions to be exactly 1/16th step apart (assuming 16:1 ustepping).

Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]
Sorry, only registered users may post in this forum.