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Fun Questions and Answers of Molds

"How are you going to get a Tech to sign his own death warrant?" He isn't. His increase is financed out of NOT having to hire additional unnecessary operators. This isn't "up to management's satisfaction" The projects and training the tech receives are agreed to before the program begins. Minimum achievement standards are agreed to IN WRITING before the program begins. You're right 'improve overall productivity by 50%" would be a sucker punch. But it might be achievable on a few molds. When everything is in writing, Management, the Tech, AND ME get a copy of the agreement. The tech will have an agreed to time frame to complete his work. Let's say he's on a project to install 5 robots and management won't purchase them within the time limit. It isn't his fault and he cannot be 'dinged' for it. Once the projects are agreed to the Tech merely has to prove he met the mutually agreed to goals by the measurement systems he and management previously agreed to. If management welches at the end of the program he'll still get his certification. But he'll also have an excellent case for Breach of Contract.

NOW for the Fun answers:
(A) 'Why is the cooling time THAT long" -
ANSWER: At that exit temperature, after everything else has been optimized, it's the shortest time to get customer acceptable parts
WRONG answer - The mold maker screwed up the shrinkage

(B) "in plain language how do you duplicate the process in machine "A" when you put that mold in machine "B" that has a different size/capacity injection unit and clamp and not start from scratch?"
ANSWER - it's all volumetric translations. The part must fill in the same time. It's volume, required melt or mold temperature, open/close distances, packing pressures or any of the time settings hasn't changed. Water temp has to be the same, water flow must be turbulent although the Reynolds Number might be different.

C) Even better "How do you know that waterline hookup is (1) optimal for that mold and (2) identical to the last five times you ran it?"

YOUR ANSWER: reynolds calculation and/or delta P as for pattern I consult the water line diagram. CORRECT
COMMENT - you'd be amazed how many people don't use waterline diagrams.

(D) And, the ultimate ship sinker "what is the ONE cause of short shots

YOUR ANSWER: There is no ONE root cause for short shots. Wrong. But you actually gave the right answer later on. "You didn't get enough material in the cavity"

From that statement (where insufficient fill IS the root cause) you can now look at the SEVEN Variables : Heat, Pressure, Time, Speed, Position, Environment, and Equipment and find the possible individual causes.

The problem is that if you focus on only one individual cause i.e. Viscosity you'll only choose speed or possibly heat as the solution. If that doesn't work then you try another cause. The trouble with this approach is it is random. What I teach allows you to eliminate causes that don't contribute to the problem and concentrate on all those that do in an efficient manner: Speed, clamp position are fast and easy to change. Temperatures take longer to stabilize.

The problem (as you so wonderfully stated it) is when someone states "I don't have time to optimize the process. I am too busy putting out fires". They only FIX problems they don't SOLVE them.

Wanna not be too busy putting out fires? Don't let them start in the first place.

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