Hi!

I havnt used my mendel90 dipond the last couple of years. When starting to print now it skipps steps in the y-axis after 2-3 layers. I remember that i had this issue a couple of years ago, but never figured out of it.

I have tried the following, but the y-axis keep skipping steps;
- Thighten up the belt.
- Printing at 30, 40 and 50 mm/s.
- Measured the y-axis movement on the print, and it is not a function of 2,5 mm.

I read something about wrong aceleration settings in the firmware for the Melzi board. And thouht I should check that out. Here I really starts to struggle.. I cant find the original firmware file, nor the softwares the followed with the printer. So basically I need a "guide for dummies" on how to find the needed software, how to use it, and where to change the acceleration settings.

Thanks in advance!

I read some more around in forum threads, and the movement of the Y-axis has an offset multiple with 0.8 mm. So I guess it must be the stepper motor that is slipping?

The firmware was supplied on the SD card shipped with the kit and you should have subsequently calibrated E steps and Z to customise it for your machine. If you have lost that version there is a copy here: [github.com] but you will need to calibrate E and Z again.

The line that effects acceleration is this one: [github.com]. Early kits had this set to 4000, which did cause Y to skip for some people with short fast zigzags that caused resonance. There should be no problems with 2000.

The instructions to load it are in the build manual here: [github.com]

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