View Full Version : Multiple passes through same toolpath
02-10-2010, 09:12 AM
I want to make a small intricate part with arcs etc using mach 3 on a small Taig.On reading the manual it looks like M47 will get you back but there doesn't seem to be way to do multiple passes deepening each cut.Can the cut be deepened by editing the code on the machine or must it be removed to edit and homed back in for each pass.thanks.(I don't have CAM).The part is steel plate 5/16 inch thick which might be too much to do in one pass?
02-10-2010, 10:52 AM
Can you use a subroutine? if so - the main part of the program would set a Z position and call the subroutine that has teh sequence of moves. For the simplest subroutine you would have to have just X & Y moves in the subroutine. I am sure that if you look up subroutines in Mach there are several examples of how to do it.
02-10-2010, 06:10 PM
Look in the wizards, there is a multipass wizard.
A subroutine would be very easy. Assume you cut 1/16" deep on each pass. Then you'd need 5 passes.
The main program would have:
M98 P0002 L5
And the subroutine would look like:
G0 Z-.0625 F?
... (cut profile)
02-13-2010, 09:02 AM
Couldn't find anything that looked reasonable in "Wizards" but while looking found the answer under automatic Z control family using "inhibit Z"-thanks.
03-07-2010, 10:39 AM
BTW, assuming you want to follow exactly the same path, but with deepening cuts, you can make any CNC perform this task using tool offsets.
You get a tool length offset for Z depth and a tool wear offset for tool diameter. Just use the offsets to tell the controller that the tool is longer or bigger than it really is. The end results is a different path with less depth of cut. Each pass needs to reduce the exaggerated offsets.