Old Machinery

We often blame the old machine when we have a quality problem. This old thing doesn't work like it used to. At some point, we end up buying a new machine. But the problem wasn't the entire machine. Some part of it had failed or worn out. The machine ought to have a much longer life when you replace worn parts. The trouble is, a lot of people give up the hunt for the elusive broken part of the machine.

A company I worked with was dispensing fine powders as a part of one of their processes. The reject rate was too high because the amount of powder dispensed was sometimes too much, other times too little. The problem was in the variability of the dispensing process. A new, half million-dollar machine was purchased to replace the old machine and for a while, both machines worked side-by-side. Now get this. The new machine was worse than the old one! More overweight rejects. More underweight rejects.

I was able to work with the company on this specific project and we determined the root cause of the old machine's variability problem. It was corrected and was producing over 99% quality product (up from 85%!) in a few weeks. The new machine was significantly different and required some pretty serious redesign work. My contribution was over and I moved onto other assignments but I hear from people still there that the new machine is in the corner. No longer needed.

Old machines don't fail. Parts of it wear. The root cause of many old machine problems turns out to be a hundred dollar part. It's well worth spending the time to figure this out.