Henry,
The reader head (not the scale) on the Z axis (longitudinal) got knocked out of position when the carriage pushed the reader head to the end of the scale housing and moved the bracket. It was apparently enough movement to cause the thin cast aluminum "stalk" of the reader head (extending up into the scale housing) to rub against the scale housing seal and wear right though the aluminum casting, seen as the crusty-looking "T"-shaped thing and the now-separated base it used to be attached to.
In looking at the bottom photo, just imagine running that reader head into the end of the scale. It easily moved the bracket at those two long slots, and neither I nor my dad ever "felt" any problem. It took perhaps a year or less to wear right through as you see it.
Sorry about my optical delusion in not realizing that I was looking at just a stack of fender washers there.
I suggest you run the cross-slide all the way in to the stop, then place the scale housing as far back as is practical. The goal is to get the reader head itself far from being struck by the tailstock being slid forward, or anything else for that matter. I sense that's how the one on my dad's lathe was done, but we'll never know. The installation was already done when I got the machine for him.
The reader head (not the scale) on the Z axis (longitudinal) got knocked out of position when the carriage pushed the reader head to the end of the scale housing and moved the bracket. It was apparently enough movement to cause the thin cast aluminum "stalk" of the reader head (extending up into the scale housing) to rub against the scale housing seal and wear right though the aluminum casting, seen as the crusty-looking "T"-shaped thing and the now-separated base it used to be attached to.
In looking at the bottom photo, just imagine running that reader head into the end of the scale. It easily moved the bracket at those two long slots, and neither I nor my dad ever "felt" any problem. It took perhaps a year or less to wear right through as you see it.
Sorry about my optical delusion in not realizing that I was looking at just a stack of fender washers there.
I suggest you run the cross-slide all the way in to the stop, then place the scale housing as far back as is practical. The goal is to get the reader head itself far from being struck by the tailstock being slid forward, or anything else for that matter. I sense that's how the one on my dad's lathe was done, but we'll never know. The installation was already done when I got the machine for him.