Rob Neilley
Editor-in-Chief, rneilley@immnet.com

1. It leaks oil like it's incontinent
2. The paint is wrinkled and coming off
3. The memory fails (EEPROMs have a limited read/write service)
4. The toggles in the clamp knock around like arthritic joints
5. It is a plunger, not an R-Screw
6. When it (or its data collection) is found wandering and can't tell you how it got there.

But seriously folks, I got nothin!

Tomchak

At what age do you consider an injection molding machine to be "getting old"?

In the “good ol’ days” of injection molding, a commonly held belief was that if a press was more than seven years old, it should be replaced. This arbitrary figure really didn’t take into account cycle speeds, resins run, and maintenance (both PM and reactive) and upgrades given the machine.
“Nowadays” molders look at hours run rather than years of age of a press and maintenance and repair history of a press is heavily weighed, as well as availability of spare parts. With modern hydraulic filtration, analysis and other preventative maintenance methods, there is no reason that a press can’t perform indefinitely.
There exists a “world class” definition for an injection molding machine’s variability in pressures, times and linearity, but often a molding press doesn’t have to meet world class standards, and some presses don’t or didn’t meet world class standards when new. The late Denes Hunkar did a lot of research into classifying the robustness of a molding machine. Bill Tobin makes these available in his book on mold tryouts and (for free) on his website at wjtassociates.com. See Robust Machines, the website even has a free spreadsheet for testing the robustness of a press and classifying it according to Hunkar’s 1 thru 9 system
The RJG website has excellent articles on testing and classifying molding machines including; Has The Molding Machine Been Tested?, by Gary Chastain.
John Bozelli’s scientificmolding.com gives the Molder more tools to test the robustness of a machine.
Finally, there numerous articles on the subject in Injection Molding Magazine, as well as posts on the immnet.com forum. Do a search; there is a lot of free material on the subject.
As much as I like to see high molding machine sales, the age of a molding machine, like that of the molder, is relative. Both, if maintained, can never get “too old”!

Brent Borgerson
Senior Process Engineer (Older Molder)
Matrix Tooling/Matrix Plastic Products
Wood Dale IL

www.matrixtooling.com