The Precision Grinding of Industrial Tools

The entire metalworking industry depends on precision grinding in order to build the necessary tooling for mass production. Without this highly accurate grinding process, manufacturing as we know it, would come to a screeching halt.

As a young man just entering the tool and die trade, I was astonished at the different types of grinders in use. After school I held several different jobs that all involved precision grinding. One of the more interesting machines was an ancient grinder, similar to a Blanchard grinder, that made some kind of huge parts to dredge the Mississippi River, where I lived at the time. What was amazing is that this grinder was so old, yet still was very accurate.

Another machine that bewildered the life out of me, was the centerless grinder. I ran one for about a week and never did quite figure out why my round bushing didn’t just get destroyed by the two rotating abrasive wheels. If you have ever seen one, you know what I mean.

We also had an enormous CNC surface grinder with a huge wheel that scared everybody. The operator would line up a dozen or so parts, and fire up the wheel. The obvious thought was about the magnetic chuck holding all those parts: what if they came loose? There were numerous big dents on the guard that attested to the fact that this had happened before.

This wheel was a typical aluminum oxide grinding wheel, and the coolant sprayed everywhere. Apparently, nobody seemed concerned about the lack of an industrial dust collector.

The first time I ran a tool and cutter grinder was in a mold making shop. I was not only making a cutter, but using the machine to cut ribs in a core block. Unfortunately, nobody told me that I needed to feed the cutter at both ends of the cut, and my rib was shaped more like a j than an l. So, I had to grind another carbide cutter on the diamond grinding wheel and start over again.

Probably not a day goes by when a mold maker is not required to use a surface grinder. This machine is capable of a wide range of operations, all of which are highly accurate. With the right grinding accessories, almost any contour or shape can be ground. Some of the necessary accessories include sine plates, magnetic chucks, wheel dressers, diamond dressers, coolants, height gauges, gauge blocks, dial indicators, pin gauges, magnetic squaring blocks, vee-blocks, and spin fixtures.

Many companies manufacture these tools, some of the better ones include Hermann Schmidt, Harig, Tesa, Starrett, Brown and Sharpe, and Mitutoyo.

Over the years I have used many different makes of grinders. Deckel, Elb, Parker Majestic, Brown and Sharpe, Mitsui, and Okamoto are just a few of them. Some of these companies have struggled to stay innovative and competitive and have either merged or gone out of business altogether.

Post time: 06-12-2017