The Four Arm Caliper Tool (FAC) Version 2 is a Python-based application that enables loading, visualizing, and analyzing oriented four-arm caliper logs. The first version of FAC was developed by Niederhuber (2025) in Matlab. This version is a modification and an extension of the previous Version with new import and export format as well as an improved tab/window handling. Also some miner bugs have been fixed.
The software provides an interactive graphical environment built with PySide6 and Matplotlib, allowing users to explore borehole geometry, identify breakout intervals, and determine stress orientations following established geomechanical analysis principles. Supported input formats include .las, .dat, .csv, and .txt files.