Our 75 HP gang rip saw broke down yesterday, and we had to pull the pressure roll assembly off to repair it. I thought you lumberjocks might get a kick out of these photos. My brother and I did a little calculating and we’ve had this saw for 10 years and figure that we have fed thru this saw about 100 million linear feet of boards. The operator forgot to tighten the internal arbor nut and when he turned on the saw the inertia of the saw caused the nut to tighten up essentially making it nearly impossible to get off. We rarely have to remove the pressure feed roll assembly. It is a major job. We did this in order to be able to have room to handle a 3 ft long pipe wrench. The wrench would not initially budge the nut so we had to heat the nut up with a torch. It finally broke loose.
This is the side view of the saw.
This is the view of the saw after we removed the pressure roll assembly. The large hex nut on the end is the nut that would not come off.
This is pressure roll assembly that had to be removed in order to get it out of the way.
This is the arbor sleeve containing the saw blades. Unfortunately the spanner nut on the end of it would not budge either. There is a plastic spacer that melted from the heat and it melted enough to make it nearly impossible to remove it. We had to weld up a special tool that would lock into the keyways on the bottom of this arbor and then we layed it on to 2 sawhorses and used the special tool on one end and the 3 ft pipe wrench on the spanner nut. When even pounded on by a 4lb hammer the wrench would not budge. The only thing left to do was take it to a machine shop. They put the whole arbor sleeve saw blades and all into one of their lathes and turned the spacer nut down to the threads. Our lathe was not big enough to do this. Total cost of the repair was two days down time on the saw and probably $500 or so for the nuts plus the machine shop time. Fortunately most of my days here at the plant go a little better. We got it back together on the first day but the other day is waiting on the nuts to arrive. It should be going again around 11:00 AM on Friday.
-- If a man does not keep pace with his companions, perhaps it is because he hears a different drummer. Let him step to the music which he hears, however measured or far away. Henry David Thoreau