Beware, U1 can probe bed at too hot of a temperature

U1 Toolchanger
1

I’ve been printing PLA on my U1 for a while now with hundreds of hours with few issues but recently started doing some PETG and I’ve found an issue with the SnOrca GCODE that may damage your build plates when using filaments that use higher temperatures (Over 235c print temperature)

It seems that the GCODE prior to probing to set the probing nozzle temperature use the print temperature minus 90c. So when printing PETG that means probing the bed at 165c. If printing something at 300c it would be probing the bed at 210c. Most build plates do not recommend nozzle contact over about 130-140c. I already have 3 melted nozzle marks on my Cryogrip plate due to this.

nozzle_damage
nozzle_damage1600×1208 277 KB

Check your Machine start GCODE for “M109 S{nozzle_temperature[initial_extruder] - 90}” or similar, just prior to G28 Z moves and consider changing them to a static 130-140c setting with M109 S140 (Some lines may reference a toolhead and require slightly different changes).

2

Thanks for the heads up! The pre-print gcode indeed doesn’t seem to be very optimized yet.

3

Hi Mirlen. Have you opened a support ticket for this?

4

To be fair, this is a Snorca issue, and is under the wrong section of the forum.

5

Is it? I’m not sure. If the issue is in the G-Code, then yes. If it is in how the U1 firmware responds to the G-Code, no.