Chuck Schultz is a licensed engineer, Gear Technology Technical Editor, and Chief Engineer for Beyta Gear Service. He has written the "Gear Talk with Chuck" blog for Gear Technology since 2014.
[starbox]How long should gear manufacturing equipment last? I posted before about some very “veteran” gear cutting machines that are still earning their keep on a regular basis. It occurs to me that we might be holding our shops back by sticking with machines that are no longer capable of producing quality parts in a competitive cycle time.
Some industries replace equipment much more frequently, their decisions made by the pure economics of their product. You no longer see glass containers in most departments at the grocery store. The shift to plastics is almost complete outside the adult beverage department, spurred by reduced breakage and lower transport costs. Of late I have noticed that even the shape of the containers is changing to reduce the amount of “dead air” in bulk shipments. Lighter products have load sizes determined by volume, not weight.
My interest was piqued by a client’s questions on gear shaping machines. They have lost confidence in their 1950s vintage shaper and asked for advice on what manufacturers and models they should look at. Fortunately, I know people who know people in the machine tool business and ought to be able to point them in the right direction quickly.
Over the years my employers bought lots of new and used equipment. Most of the new stuff was related to gear grinding where only the “latest” was deemed worthy of consideration. The improvement in productivity was so dramatic you hardly needed MBA level analysis skills to make a decision. Also, all of the newer machines were so much better than the old ones you couldn't make a bad decision.
We made lots of bad decisions on used equipment though. Early NC machines often had electrical bits that were no longer supported. Many had insufficient power to “pull” modern chip loads. Some were just not reliable enough for use in “cellular” arrangements. We learned the hard way that making great ground tooth gears required excellence at each step in the process. You cannot “fix” a bad blank at gear grinding and hope to be competitive.
Care to share your experience with replacing gear machines?