July 2007 Edition

From The Shop Floor

Dave Sterling, Application Engineer Ansco Machine Co.

An Old ‘Friend’ Retires After 29 Years

Knowing when to let go is a tough decision, often it’s the tell-tale signs of age that make it obvious . . . with both people and machines

I keep telling myself, “it is just a machine.” But, I still feel nostalgic when I see the spot where it once sat. No longer is the hulking green frame sitting there, its monstrous turret visible through the partial enclosure. I miss the hum of the spindle motor when it was roughing, with the wonderful sound of chips landing in the pan. I imagine I can still hear the squeal of a drill, followed by the unmistakable thwap of a drill disc smacking against the door. It is gone, and it feels like a friend has left my life.

Okay, it wasn’t a friend; it was a 1978 Warner and Swasey 2-SC. It joined our company fleet in 1993 as our first CNC. It was a staunch worker from the first time it cut metal for us. It had a 60 hp spindle motor, 12 massive tool stations, and a 15" hydraulic chuck that could squeeze the tar out of anything. Over the years it made a lot of parts, from drilling 2.25" holes with an inserted drill, to the delicate finishing of hydraulic components.

Now it’s gone. They said they were taking it out into the country where it would have a good home with a farmer. Yeah. Right. I’ve heard that story before.

My brother Jeff and I both learned CNC lathe operations on the 2-SC. It was the machine that led my father to learn a CAD/CAM system so he could program it. The 2-SC played a major role in the development of our company over the years. Unfortunately, recurring electrical glitches, a cumbersome control, and a premium on floor-space brought the end of an era.

The new machine that replaced the 2-SC has many advantages over that old-timer. The new machine uses all of the same programs as the other machines in the shop. That’s where the 2-SC caused the gnashing of teeth until we learned its foibles.

Back When We had to Know Stuff

Programming and editing code for the 2-SC’s Allen-Bradley control was an art form in itself. For starters, its code was radial, not diametrical, making a calculator a necessity for even basic edits. Gear control of the spindle was done through spindle maximum commands. Specifying an odd- numbered spindle max put it in low gear, an even-numbered spindle max put it in high. If you didn’t put in all the leading zeros, you were in for a surprise.

While the 2-SC was an early predecessor to a tool setter – a bar and arm acted as a positive stop for boring bars – it left much to be desired when using a non-standard tool. Since the machine did not have tooling data offsets, the operator had to enter all information about the tool during programming. A tooling notebook kept handy was required when programming. If a boring bar change was needed, it was back to the drawing board.

The most difficult things about the machine, from an operator’s point of view, were the complicated commands needed to do simple tasks. It seemed like nothing was easy or straightforward. To turn on the spindle required entering a speed into the control – SS, 0150 – and hitting either the spindle “clockwise” or “counterclockwise” button. Make sure that the leading zero is in the right place, so the spindle doesn’t go faster than expected! Moving the turret to a new location was a similar two-step operation, daunting for a novice.

I’m not advising anyone to get rid of their old machines. If they still do the work efficiently and well, they earn their keep. Our 2-SC served faithfully for 30 years, and competed with machines a quarter of its age. It is a testament to the solid design and construction that the machine was mechanically sound after all these years. But, like all of us, it suffered from the effects of age with annoying drawbacks here and there. It was time to put it out to pasture.

For all of its drawbacks, I’ll still miss my old friend.

 Dave is responsible for programming, tool selection, and fixture design for Ansco Machine’s 20 CNC machines in Peninsula, OH. He’s been working in a machine shop since age 12, starting by drilling holes on a turret lathe and making simple parts on a Bridgeport.

What do you think?
Will the information in this article increase efficiency or save time, money, or effort? Let us know by e-mail from our website at www.ModernApplicationsNews.com or e-mail the editor at pnofel@nelsonpub.com.