hello: Have worked most of my life with machines from tool and die shops to heavy machinery in a steel miil. Now that i'm retired have my small shop in my back yard and bought a Rockwell catalog number 17-540 drill press, I believe its a 17 inch floor model. Pretty much similar to the one you have in the forum which is I believe a 17-600 one.I bought this machine for barely 75$ it was in the back of someones back garage. The machine is basically in excellent condition, it had a three phase motor which I changed to a single phase 1 1/2 horsepower motor. it worked perfectly,I made sure that it was properly oiled, and free spinning, it is also a variable speed machine, which I think is very nice and practical, however all of the sudden the spindle will go down only about 3 inches and it stops. it feels like there is something soft stoping it from traveling down, the stop is somewhat soft no a solid hard stop, I wonder I somebody could give me an idea what the problem could be, I'm looking for obvious things that could cause this, but can't find it.