Using Tool Length Offsets (TLO)


It has become the preferred method of handling adjustments for tool length with the RapidChange ATC system using tool length offsets (TLO). This method allows the user to set their work Z however they choose and employ seamless tool changes and adjustments for tool length without resetting the work coordinate offset. This method records a value during the tool touch off portion of a tool change to the TLO for that particular tool. It then applies that offset using G43.

Master Tool Reference

Though most systems encourage using a master tool as a reference point from which all other offsets are calculated, we have found that this method is unnecessary for the RapidChange ATC system. We have found the simplest method is to use the offset from Z home as the TLO for any specific tool. The TLO for a tool then becomes the Z machine coordinate at which the tool setter is triggered during the tool touch off routine. Using G43 we then apply this offset to the existing work coordinate. This allows work Z to be set using any tool that has it’s TLO applied using G43. Each subsequent tool change and touch off will then adjust the applied offset according to the tool length.


When using one of our integration packages with a tool touch off that uses TLO, simply load a tool and let it run the included tool touch off macro. This will record the TLO value for that tool and put you in G43 mode applying the recorded offset for that tool. At this time you can set your work Z using your normal process. Upon each subsequent tool change the difference in tool height will be applied automatically.

Updated on February 9, 2024

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