Again – good, but still not a safe ap pli ca tion What if the argument is also defined as negative?


Us ing the ABS func tion – and a lit tle in ge nu ity – the G65 Z-depth ar gu ment can be pro grammed


with ei ther a pos i tive value or a neg a tive value, and still get a neg a tive cut ting di rec tion (Z-mi nus di rec tion) Im pos si ble? Study the next ex am ples – whether the Z-depth ar gu ment is de fined as pos –


i tive or neg a tive, only one macro is used with a guar an teed di rec tion of the toolpath into the


material:


2 Positive Z-depth argument:


G65 P8999 R20 Z156 F1750


Z-depth argument is positive


Boring Machine


2 Busway Press Clamp Machine Negative Z-depth argument:


G65 P8999 R20 Z-156 F1750


Z-depth argument is negative


The key to suc cess is the macro call It must use the ABS func tion that will con vert the ar gu ment


into a pos i tive value Then us ing a neg a tive Z-value, the tool mo tion will al ways be into the part:


G99 G81 R#18 Z-[ABS[#26]] F#9


Negative custom processing machine Z guarantees negative tool motion


Note the Z-depth en try – it must neg a tive within the macro! Once the macro is proven and saved,


it can be pro tected by a pa ram e ter set ting, so there is no dan ger of an ac ci den tal change What ex –


actly will hap pen when the above macro state ment is pro cessed?


If the spec i fied ar gu ment is pos i tive, ABS[#26] will leave it as pos i tive, so ABS[#26] will be equal to 156 Since the Z-value in the macro is fixed as neg a tive, the neg a tive sign will pre cede


the stored value and the re sult will be Z-156, which is the de sired and cor rect en try


If the spec i fied ar gu ment is neg a tive, ABS[#26] will change it into a pos i tive value, so the ABS[#26] will be equal to 156 Since the Z-value in the macro is fixed as neg a drilling tools tive, the neg a tive


sign will pre cede the stored value and the re sult will also be Z-156, which is the cor rect en try


NOTE: This ex am ple is sim ple and per haps even clever Al though it il lus trates a rel a tively


small macro func tion, it is in cluded here not only for the pur p