A new technology exists that ensures proper grease distribution to the spindle bearings over long duty cycles. This new grease lubrication system applies a shot of grease every 70 hours to each of the spindle bearings to ensure proper lubrication.

What is unique about this new technology is that typically grease-packed spindles are packed for life and never get re-lubricated. It’s quite normal in moldmaking for spindles to be running at top speed for many hours, resulting in the grease being thrown out of the bearings by centrifugal force. Once the grease goes away, the heat begins to build, the bearings begin to fail and your spindle is done. So by having a re-lubrication system, there effectively is no limitation on spindle hours, as the spindle’s always being greased.

Now that we have a well-lubricated, cool spindle, and we’ve removed a majority of the heat, we still need to compensate for the effects of the remaining heat in the system. A system called dynamic thermal compensation should be employed. Sensors or thermal couples are mounted to the machine head and base casting to monitor head temperature versus ambient (room) temperature. While the machine is cutting, the system is continuously measuring and compensating for thermal expansion. Every 15 seconds the system compensates for the growth of the machine, down to one micron.

The machine is always alive, moving to compensate for heat-driven growth. Other builders address thermal compensation, but not dynamically. They don’t measure all the time (if at all). The theory, “We know this machine grows a certain amount, so we’re going to compensate just for that amount.” This approach is a huge mistake because the assumption is that the machine heats and cools the same way, every time, under all duty cycles.