Predict Tool changes and start heat-up beforehand

[shirnschall]

I recently added a second extruder to my printer and I noticed that the printer is waiting for the tool to reach the set temperature after each tool change. Is there a way to predict when tool changes will occur (maybe using the simulate print feature?) and start the heat-up process such that it is ready around the time the tool change happens?

Is this a feature yet? Unfortunately, I could not find much regarding this issue online.

[dc42]

It's not a feature yet, although I hope to introduce it eventually pn the Duet 3 series (the older Duets have insufficient RAM).

[shirnschall]

@dc42 Thank you for the quick reply

[dc42]

BTW some slicers (e.g. Cura) already do this.

[shirnschall]

@dc42 That is interesting, I guess I will give Cura a try.

I really thought about your previous comment and how the duet2 has not enough ram for such a feature.
I am not very familiar with the hardware limitations of the duet boards but this is how I would do it:

1. When simulating the print add a comment to the end of each line with the time at which this command is executed during simulation
2. Measure the time it takes for each tool to warm up during the initial heat-up (when the print starts)
3. Parse the gcode file line by line until we find a Tn command
4. Parse the gcode file backwards, line by line (starting from the last character in each line until we find the ';') starting in the current line (where we found the Tn)
5. If we find a timestamp at the end of a line such that the distance from this timestamp to the one at the tool change command is greater than the tool heat-up time, insert the gcode command to start heating up the tool in this line

I am not sure if this is a viable method.