In the Trenches: The Next Step in Minimizing Press Downtime
A look at crib notes on press operation for mold repair personnel.
When I make a press call, I usually think of one more item to add to the stock on hand: a multimeter, 15-amp fuses, a small assortment of roll pins for lifter heads, etc. All of these items support the same purpose: to reduce press downtime.
This makes the next suggestion to further the agenda of minimizing downtime obvious: Train mold technicians the rudiments of press operation, at a minimum. What good does it do to race to the “scene of the accident,” make a speedy repair, and then wait 10 or 15 minutes for a mold setter or process technician to come along and start the press up again?
Generally, mold repair technicians (at least in my experience) are the highest-paid hourly employees at a molding facility. So now, not only is the company losing money on press time, but also one of the highest-paid employees is waiting around not being productive.
(By the way, walking away from a repair is not usually a good idea. Its one thing if you’ve just replaced a broken water fitting, but if you were in the press addressing a part-defect issue, it’s always good practice to stay and verify your work. If the repair was not effective, there will be even more lost time waiting for your return.)
Following is an example of instructions I initially prepared for myself and then shared with others in my department:
• Don’t just take notes.
• When you are being coached through the process, insist that you be allowed to push the buttons.
• Go through the process several times, take notes, then go through it following your notes with an observer (a silent observer).
• Be thorough, specific and detailed.
• Take pictures.
• Make it “Press Operation for Dummies.”
Because there can be several different scenarios given your particular setup, the length of time the press has been idle, the specific repair verification needed and so on, I recommend you start with the most generic scenario then build on it as technicians develop some comfort level with press operation. It can be intimidating to push “Cycle Start” without panicking, wondering if you left a stone sitting on the die-lock.
Almost all of our presses are outfitted with robotic demolding and degating. Most of our in-press repairs are “quickies,” and our most-common resin is fairly forgiving when it comes to residence time in the barrel, so the repair instructions outline the process for getting the mold back on auto-cycle, no barrel-purging required.
Once the repair notes are verified for accuracy, it’s simple to format them in an Excel document and add circles and arrows. Visual aides are always an effective means of education. Print the instruction pages in color and put them in a sheet protector in a notebook that also has some blank sheets for taking notes at the next press call. Depending on your mix of presses, this may be a lengthy process, but in time your manual should be complete and should start paying you back for your efforts.
There are two methods for optically polishing aluminum - knowing the right one for your project will save you time and money.
Mold cleaning is just one part of a systematic and comprehensive approach to mold maintenance. Here’s one moldmaker’s strategy for injection mold cleaning and an explanation of where and why different techniques are employed.
A look at non-destructive cleaning processes for complex molds that require the removal of tenacious surface contamination to ensure surface quality and longevity of precision mold and molded part surfaces.