Brake repair gets important Niles lathe back in service.
In February 2010, I repaired the main brake on a WMW Niles lathe of about 39 x 160 inches. This lathe was built before the re-unification of Germany, and service parts and information are very hard to come by.
First I performed hydraulic tests to see if operating pressures for the clutches and brake were correct. They were, so I concluded the problem was probably in the brake itself. Thankfully this is a pretty well designed machine; removing the headstock housing cover gave good access to important components.
The wet-disk main brake is located at center right of the photo above, with a close up below:
The brake housing interior is accessed from the front plate behind the headstock.
Disassembling the brake innards, I found the friction plates badly scored and galled, causing insufficient friction to properly (and safely) stop a spinning headstock and workpiece.
I located an excellent source for such disks overseas, but we couldn’t match up the ones we needed with stock items. We could have a set custom made but it would take a while, so we surface ground the existing plates and continued using them. It will be interesting to see how long they hold up!