I had a couple of cuts start to go wonky - to the point where the torch was not cutting all of the way through. At first I thought of a couple of other items like issue with voltage causing the THC to cause lifting, but in the end, it turned out to be the IHS.
What was happening was the connection from the lead wire to the actual mounting wire, clear plastic covered spade connection, was intermittent. This was causing different zero reference as it appeared when the z axis was in motion. I had a high z axis through the process and very large voltage readings that lead me to look.
When I operated the IHS by hand, It would not respond correctly and show connection where there was none, and vice versa.
Anyway, cut out the old connection and replaced with new connector and no more issues. I did the same thing to the other side just to eliminate the potential for failure there.
In the end, I dont think the crimp was the best and over time the connection was breaking.
Just thought I would share in case someone else has the same thing happen.
Bill