Are there any guidelines for the maximum current for different thicknesses of PCB tracks ?
You can use any other PCB pcb trace width calculator
such as http://circuitcalculator.com/wordpress/2006/01/31/pcb-trace-width-calculator/
Thanks very much, that's really helpful
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The process supports design scales of 300
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Brand new interactions and interfaces. 
Easy to use and quick to get started. 
You can use any other PCB pcb trace width calculator
such as
http://circuitcalculator.com/wordpress/2006/01/31/pcb-trace-width-calculator/