Calculating steps per mm we are struggling to calculate steps per min on our z axis (with a lead screw with a pitch of 20mm) The onboard driver is 16 microstep, but for the z axis we are using an external driver that has 10 microsteps which runs a nema 34 1.8 with a 50:1 worm gear We have followed formulas, and also an online calculator, trying with 16 and a 10 microstep, and tried the values with no success Are we missing something obvious here ? https://reprap.org/forum/read.php?14,768590,768590#msg-768590 Tue, 21 Jul 2026 09:03:57 -0400 Phorum 5.2.23 https://reprap.org/forum/read.php?14,768590,768677#msg-768677 Re: Calculating steps per mm https://reprap.org/forum/read.php?14,768590,768677#msg-768677
Quote
frankvdh
20mm seems to be a very large value for the screw pitch. Are you sure about that?

100% sure. This is not a small printer. The print volume is over 4m³
We are using a geckodrive as an external.
Will the microsteps come from the external, or the onboard?]]> Vital1 Mechanics Thu, 18 May 2017 05:05:37 -0400 https://reprap.org/forum/read.php?14,768590,768643#msg-768643 Re: Calculating steps per mm https://reprap.org/forum/read.php?14,768590,768643#msg-768643 o_lampe Mechanics Thu, 18 May 2017 02:06:45 -0400 https://reprap.org/forum/read.php?14,768590,768623#msg-768623 Re: Calculating steps per mm https://reprap.org/forum/read.php?14,768590,768623#msg-768623
Working on 20mm pitch, one turn of the screw would result in 20mm movement.

At 1.8deg/step (200 steps/rev), one step would be 0.1mm. At 1/16 microsteps that would be 160 steps/mm.

At 1/10 microsteps and 50:1 reduction, that would be 10*50*200 = 10000 steps/turn = 10000/20 = 500 steps/mm.]]> frankvdh Mechanics Wed, 17 May 2017 19:02:35 -0400 https://reprap.org/forum/read.php?14,768590,768619#msg-768619 Re: Calculating steps per mm https://reprap.org/forum/read.php?14,768590,768619#msg-768619 Dust Mechanics Wed, 17 May 2017 18:03:49 -0400 https://reprap.org/forum/read.php?14,768590,768590#msg-768590 Calculating steps per mm https://reprap.org/forum/read.php?14,768590,768590#msg-768590 The onboard driver is 16 microstep, but for the z axis we are using an external driver that has 10 microsteps which runs a nema 34 1.8 with a 50:1 worm gear
We have followed formulas, and also an online calculator, trying with 16 and a 10 microstep, and tried the values with no success

Are we missing something obvious here ?]]> Vital1 Mechanics Wed, 17 May 2017 14:48:43 -0400