UM2 to UM+ upgrade with Aliexpress parts

[sysmop_Israel 0]

Hi all!

 

I got an old UM2 and wanted to upgrade it to 2+... Since I didn't feel like splurging, I got an AliExpress mod for 14USD.

Here's the part: https://www.aliexpress.com/item/1005004044844756.html?spm=a2g0o.order_list.order_list_main.27.61c81802HmS25G Note that it comes without requires screws, so get yourself 4 M3X8 screws and 2 nuts for the case itself (4 screws for the motor, 2 old ones from the motor for the case).

 

After that I realized I needed a firmware fix, so I got everything I needed installed and used the UM2.1 firmware from GitHub: https://github.com/Ultimaker/UM2.1-Firmware

After I finished updating, I fires her up and the Z-axis flew up like a rocket and hit the hotend! OMG

 

I started reading online and found that UM2.1 uses 400 step/mm vs. the UM2 that uses 200 step/mm for the Z axis! ( I thought it's only for the extruder motor...)

after several hours I managed to get it working, here are the correct values for this upgrade:

 

line 371: #define DEFAULT_AXIS_STEPS_PER_UNIT   {80.0,80.0,200,282*3.3}   // default steps per unit for Ultimaker2.1 JarJar ###My setup uses 11:36 tooth ratio, so 3.3 is the correct factor)

 

Now I still have a few issues with material flow, but I hope to fix them in the coming days.

I'll keep you guys posted!

 

Tomer

 

UPDATE:

The correct E step/mm is: 1272

Hope this helps someone

Edited March 19 by sysmop_Israel