Minimum step distance

Hi,

Would anyone be able to tell me the minimum distance the nozzle can move during a print job for each axis? I read somewhere that the minimum amount it can be moved in a single step in the z-axis is 0.1mm. Is this true, and does anyone know what this minimum value is for the x and y axes? Assuming that the thickness of the print material coming out of the nozzle is not an issue. The printer I'm looking at getting is a MendelMax 2.

Thank you

The minimum distance is exactly one motor (micro)step. Your steps/mm value in your firmware tells you to how much this translates in millimetres.

There are also numerical limitations in the firmware. For Teacup firmware this is 1 micrometer, for other firmwares it depends on the distance moved (float variable).

A 0.1 mm limitation is likely a practical limitation, like it doesn't work well to print in 0.01 mm layers.

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Generation 7 Electronics	Teacup Firmware	RepRap DIY

Thank you for the reply. Would small distances such as these (several microns) be possible in the x and y axes too, or would the belts result in less accurate positioning compared to the leadscrews on the z axis?

accuracy beyond 0.1mm is better accounted for by feedstock variation and diameter thickness, i read somewhere about nozzle accuracy being limited to half of the nozzle diameter.

here is a nophead article about speed of object and polygon complexity changing amount of material extruded, this is one reason small circles are too small.
[hydraraptor.blogspot.com]

with this consideration belts are as accurate as needed since placement beyond 0.1mm is pointless, as flow rate varies from feedstock diameter, and the type of corner your part has. skien forge has settings to compensate for this a little bit called stretch. i think cura handles this automatically,

however this is only my opinion and tech does change, and firmware and software are both getting faster and smarter.

perhaps if feed stock flow was better regulated, an diameter consistency in feed stock was +/- 0.01mm , firmware was a lot faster and software compensated for it. i just don't think it is somewhat practical now. even professional printers require some clean up and hole sizing.

Quote
naike
would the belts result in less accurate positioning compared to the leadscrews on the z axis?

Belts have to be bendable, so they inevitably can't be as stiff as steel. For maximum precision, you want something threaded. Something in between are chains.

Still, jamesdanielv is right, there's not much point in hunting down the last micrometer. At least not anywhere close to standard printing processes.

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Generation 7 Electronics	Teacup Firmware	RepRap DIY

This won't be for a conventional printing process, and I won't be using the extruder. I just need to have accurate and repeatable positioning. I'm leaning towards using lead screws on all axes as this better suits the project. Thank you to both of you for the help

You probably want ball screws if accuracy is vital.

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