Posts: 12
Joined: Mon Jan 14, 2019 10:14 am

"Erroneous" [old_tool] value on print start.

Wed Mar 13, 2019 10:34 am

in a dual-process, dual-extruders scenario (one process for each extruder, one print profile for each process) is possible to detect a true nozzle change by some Tool Change Script code.

The problem is that Simplify3D always sets the [old_tool] value to 0 (zero) when the print start!
Considering a T0 primary extruder and a T1 secondary extruder, you will obtain the same scenario in these cases:
  • Start with T1: [old_tool] = 0, [new_tool] = 1
  • Start with T0, print and switch to T1: [old_tool] = 0, [new_tool] = 1
So you are not able the to distinguish between these cases by using IF statements; thus every GCode command written in your Tool Change Script will be injected also when the print start with the T1 extruder, and not only when the printer switch from T0 to T1.

Some possibile solutions: set [old_tool] = 1 when the print start with T1, or always set [old_tool] to a new value (ex. "undefined") during every print start (not during tool change events!)

Thank You!

P.S. otherwise it remains possible to avoid the Tool Change Script injection at the print start when you start printing with T0, using wise IF statements (ex. {IF OLDTOOL!=0} )

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