The 28 lbs of that chuck isn't going to damage the spindle or bearings. It may take a second or two longer to come up to speed when you snap the switch on perhaps, but other than that the motor will not care. A heavy chuck will behave as a flywheel and help maintain a more constant rotational speed while turning.
I have a 6" Buck 3-jaw with 2-piece jaws that weighs about 28 lbs. It has become my main workhorse on my old lathe with Babbitt bearings.
Spiral_Chips
I have a 6" Buck 3-jaw with 2-piece jaws that weighs about 28 lbs. It has become my main workhorse on my old lathe with Babbitt bearings.
Spiral_Chips