In the process of re-calibrating the Haas VF2 5-axis trunnion, I also took the time to recalibrate the rest of the probing systems on the machine.
Unfortunately, since this is the older control, there is a slightly longer process in calibrating the Reinshaw probes, and I actually missed a huge step that could have caused a massive crash on the machine. This is actually the same problem I ran into when I first calibrated it several months ago, and I'm kicking myself for making the same mistake twice.
The Haas online tutorial has you go through several cycles to calibrate each of the probes. One of these cycles includes setting a calibration bar (a tool holder with a gauge pin), and you probe the tool setter. However, I forgot to consider that the machine has no idea how long the tool holder is from the tip of the gauge pin to the spindle, and I kept getting some weird consistent offsets. I thought you would only have to measure the approximate distance, and the machine would figure out the rest, though if I thought about it, I would have realized there was no way for it to tell.
Finding the actual length of a tool without a tool probe is by taking a dial indicator and touching off the bottom of the gauge pin and setting the indicator to zero, and recording the z-axis number. Then move up to the top of the spindle until the indicator goes to zero as well. You then subtract the two z-length distances to get your tool height. I almost missed one big thing because when I touched off the bottom of the spindle, I noticed there was a lot of residue build-up, and I had to clear that away to get an accurate reading.
Once I found this number, I was able to run through the calibration cycles and finally got everything working together nicely!