Page 28 - Plastics News July 2020

Know Your Mold

Any qualified molder knows that it must understand what's mold was driven more by another product feature. Any
important to its customer and whether or not the customer qualified molder knows that it must understand what's
is getting it out of the product important to its customer and whether or not the
customer is getting it out of the product. Define the
Anthony Malone
problem; don't just identify the symptoms.
Having a mold made is a big investment for an OEM or brand
owner of any size—a large enough outlay that it needs to be Once the tool arrives, look at the project holistically and try
reliable the first time, every time. And once the tool is built to determine whether the problems described by the
and passes all tests, it's up to the molder to ensure reliable customer are related to the tooling, processing or molding
parts are made on every cycle. Truth be told, some molders capabilities of the prior molder. Review the tool
are not able to use these tools effectively, devaluing this completely, verifying tool steel, venting, cooling channels
significant and time-intensive investment. Many a times we and any other pertinent aspects.
see customers looking to transfer their molds because their Once you have the mold in the press, utilize scientific
previous molder couldn't achieve production goals with the injection molding principles to develop a process and set up
tool. the process-control variables to ensure that process is
“locked in.” In some cases, the previous molders didn't use
a robust approach in working with the tool and just missed
something. By rotating the part 360° and using X-rays to
create a precise 3D model, industrial CT scanning allows to
see the inner workings of a part without having to destroy it
for inspection. Upon receiving a mold in a tool transfer, it
must be completely verified, including its tool steel,
venting, cooling channels and any other pertinent aspects.
In addition to the application of scientific injection molding
principles, use a design of experiments (DOE) to ensure you
have identified the pertinent process-control variables and
their limits. DOE is a branch of applied statistics that deals
with the planning, conducting, analyzing, and interpreting
of controlled tests to evaluate the factors that control the
value of a parameter or group of parameters. DOE is a
powerful data-collection and analysis tool that can be used
in a variety of experimental situations. You need to know
how multiple varying factors in a design interrelate and
affect the results that you believe are important.
The Transfer Process
Why Transfer While transferring a mold from one supplier to another
usually takes between two and six weeks, our experience
The main reason for transferring a mold comes down to the
has revealed it can actually be accomplished in as little as
molder's expertise. Generally, when a mold is transferred three days. Our engineering team works with the customer
it's because part consistency is missing. Even if the molder and its engineering department from the start to identify
makes improvements, the customer has to be able to trust issues after the mold arrives. One needs to have in-house
its expertise and ability to solve problems right off the bat. toolmakers that can handle mold modifications to correct
A box of bad parts results first in a loss of confidence, errors and create fixtures and robotic end effectors if
followed by a lost order. There's a saying: You only have one needed. In many circumstances, the prior molder and mold
chance to make a good impression.
designer did not plan for adequate venting or they sized the
The first step in the process actually isn't packing the mold mold to a poor process. After trial runs, you would be able
into a crate and shipping it to offices. The first step is to use expertise in metrology to identify the best course of
defining the problem. action.
Before a company can understand why it's not getting the A lot of the timing revolves around the customer's ability to
type of product that it needs, it must know what it wants supply its own clients. Since the mold is already in use and
out of its finished product and what it should be able to contracts have been signed, customers need to keep up
do. Ask yourself: Do you know exactly what your product their inventory of parts to meet demand, all while working
is and what it offers? Do you know all of its critical to transfer the mold to another supplier who can use it more
operations? You cannot have a solution without a clearly effectively. Remember the art lies in making the transition
defined goal. For example, your customer might need as seamless and painless as possible.
“Diameter A” to be perfect. However, production of the

July 2020 28 Plastics News