MatrixLogo horizontal white

MatrixLogo horizontal white

Injection Molding and Moldmaking
with Surgical Precision

Injection Molding and Moldmaking
with Surgical Precision

Call us: (630) 595-6144

Call us: (630) 595-6144

By Gary Johansson

June 28, 2020

Here at Matrix we manufacture complex plastic components used in medical devices and other critical applications.  These parts can vary greatly in terms of size, material, and design - but they all share several characteristics that can make them difficult to inspect using traditional methods.

Performing First Article Inspections with these methods can be particularly time consuming and labor intensive.  In addition to creating fixtures for each setup, the parts often need to be “sectioned” (sawed, cleaved, ground down) in order to inspect internal dimensions that are not naturally accessible via a touch probe or optical scope.

The associated tasks may require an inspector with a high skill level and/or experience performing similar procedures.  They also open up additional steps where operator bias and other errors can be introduced.  Were all cavities saw cut and treated the same?  Do different inspectors reproduce the exact same setups?

Above that, the sectioning process itself is inherently flawed.  Sawing a plastic part to access a cross-section will almost certainly introduce its own level of error, and this error can often exceed the tolerances of the dimension and distort inspection results.  Warp, burrs, rolled edges, inaccurate trimming, inaccurate positioning of the section line and melting are all possible byproducts of manual sectioning methods.

And after all is said and done, you end up with first article data that is historically limited to the original points in your inspection layout.  So if you want to go back later on and inspect any additional dimensions, the setup would have to be recreated with the original parts.

To sum it up, performing a First Article Inspection (FAI) on complex parts using traditional methods often involves the following concerns:

  • Time consuming & labor intensive
  • Require highly-skilled technicians
  • May introduce operator bias
  • Allows for subjectivity in results depending on operator
  • Historical reference data is limited to inspection points taken from the original sample parts, making any future inspections from those samples very time consuming and possibly inaccurate
  • Requires inherently flawed sectioning process which can introduce error that exceeds dimensional tolerances (warp, burrs, rolled edges, trim marks, melting)

This is where Computed Tomography (CT) scanning excels for automating FAIs:

CT scan color map crop

  • Parts can be quickly set up and scanned, creating hundreds of thousands of data points that comprise a "point cloud." 
  • The point cloud is then aligned with the CAD model and interrogated with Volume Graphics software. 
  • A fully 3-D generated "color-map" visually indicates how accurate (via each data point) your plastic or metal parts are to your CAD model. 
  • Special software also allows us to develop an inspection program, in conjunction with the CAD model, to generate a fully annotated inspection report per the piece part print. 

In the end, our application of CT scanning technology reduces the amount of time and labor required for first article inspections, eliminates operator bias and human subjectivity from the process, minimizes the dimensional stresses caused by manual sectioning, and leaves you with easily retrievable, electronic historical data that can be interrogated repeatedly for any number of data points at any time in the future.

By Hans Noack 

Reposted: June, 2020
(Original: July, 2009)

Hans NoackI was first introduced to mold making in 1963.  Prior to that, I had worked for an architectural firm in downtown Chicago.  I enjoyed working on building designs and I had my own ideas, but my mentor stressed the need to learn and understand the basics of designing and building a safe structure that would last a long time.  I knew I had to learn all of that in order to design a sound structure, but that portion of architectural design was not fun.  My creative thoughts were put on hold and I lost interest - so I quit.

I got a job at Jewel Tea and got pretty good at playing pool around town.  I lost some, made some, and met a girl - pool took a back seat.  Then I received my draft notice: “OH BOY, what should I do?”  At the same time, my best friend Bert started a tooling apprenticeship with a neighbor who had a mold shop in his basement.  After I found out about the deferment the government offered, I asked Bert if I could possibly get a job there, too, and he set up the meeting for me.  I recognized some of the equipment, but it was the drawings I saw and understood.  “I can create those types of drawings for you.”  It was a deal and I started my mold making career!

Since tool makers supplied the armed forces with the mechanical products they needed, they were held in the same esteem as doctors.  My boss, George, requested that I be deferred from military service.  I had already passed my induction physical and was within three weeks of heading to boot camp when the deferment was granted.  Needless to say, I was very happy!

George was a great tool maker - but more importantly, he was a great teacher.  He had patience which helped us to learn, either by his instructions or from our mistakes.  “DO IT AGAIN, DO IT AGAIN.”  I heard that a lot, but it finally sunk in.  It felt great creating inserts, plates, pins, polishing, fitting and all the rest that goes into mold building.

Two years later, I got a job at Woodland Molded Plastics in Broadview.  I learned a lot about all types of tools and the molding process.  I realized how interwoven the tool and the molding press are.  One does not work without the other, and a mediocre tool will only produce a mediocre part.

From Mold Maker to Mold Designer

Hans Noack, Mold DesignerHans Noack's inspired mold designs reflect his moldmaking experience. In 1977, I started my “design only” career and contracted for some of the finest mold makers in the Chicagoland area.  This was the best learning experience I could ever have had.  In those days, all mold designs were created using a drafting board.  The designer’s challenge was to envision the entire tool - without it actually being there.  As a mold maker, I had that gift of being able to visualize a tool, and then build from that visualization.  AutoCAD was just around the corner, and I had also seen an early version of UG.  While it was absolutely something I wanted, it was out of my reach at over $150,000.

Then in 1990, one of my customers, Matrix Tooling, Inc., wanted to hire an in-house designer.  We came to an agreement and it’s been nineteen great years since then.  That was the beginning of my CAD life in the world of plastic injection mold design.  Matrix purchased UG (McDonald Douglas then.)  Electronic design was very different from board design and there was much to learn.  What makes 3D so exciting today is that anyone can view the lifelike, colorful model on screen.

Learning about molds has always been very exciting to me.  I enjoy the challenge of creating a tool that will form a particular piece part, either as a single cavity or multiple cavity tool, and thinking about: how the inserts will be shaped for machining purposes, how the cooling lines will affect the processing of a given resin used, the ejection of the part from the tool, etc. etc. Learning about why and how a particular tool has to be built has me thinking and studying all the time.

I Built the Tool that Makes that Part

In many ways, designing a tool is like designing a great structure; every aspect is important.  It must be strong enough to withstand injection pressures.  It must be machined, polished and fitted correctly.  It must eject the part correctly.  It must have sufficient cooling.  It must fit properly into a certain molding press.  With so many issues that need to be defined, there is never a boring moment.
And it’s worth all the effort when I see a part come out of a mold that I designed and built; it’s breathtaking.  And years later, when I see that part in the course of daily life, I’m filled with the same pride I felt on that initial run: “I BUILT THE TOOL THAT MAKES THAT PART.”  Usually, it’s the only tool in the whole world like it, one of a kind.  And that is a great feeling!

So why am I so thankful?  Because plastic injection mold making has given me the opportunity to create, work, make a very good living, and enjoy life, family and friends.  So many products we use on a daily basis were created by some kind of tool - mold making is a trade that will endure!

By Paul Ziegenhorn and Anne Ziegenhorn

June 18, 2018

Back in 2003, our first significant takeover program at Matrix Plastic Products was a re-shoring transfer for a major global medical device OEM. We had only limited dealings with this customer until that time, but they contacted us when they were struggling with a very sporadic and unpredictable supply of molded product from their off-shore partner. Not only were their shipments to the U.S. delayed on a regular basis, but they were also battling numerous quality issues and high scrap rates on this program. Suffice to say, the lure of low cost tooling and production had worn thin.

By quickly building and qualifying low-cavity tooling in-house, Matrix was able run enough production to keep a stream of parts flowing, which bought time for the transfer of six tools to the States. Once these molds arrived at our facility, they were disassembled and diagnosed by our tooling staff. We repaired damage, made mold modifications to enhance performance, and ran production using these refurbished off-shore tools for the next two years.

ToolExpertWebcrop

In the meantime, the customer’s demand was increasing and production was ramping up, so we submitted proposals for high-cavitation hot runner tools. By amortizing a portion of the tool cost into each part, we helped them to justify their investment by demonstrating the payback would take less than 15 months. Two other benefits of the faster hot runner tools were a dramatic drop in part prices, and the elimination of their previous quality problems. Bottom line: with Matrix covering the tool maintenance for the life of the program, the cost to the customer was both predictable and affordable.

Helping to identify and resolve the myriad of quality issues that often accompany troubled programs has earned Matrix many new customers and has led to double-digit growth in our production molding sales. A key advantage in managing transfer programs with takeover tools is our 40+ years of in-house moldmaking expertise. Upon receiving a transferred tool, our team of engineering, tooling, processing and quality experts thoroughly analyze the mold's capabilities to diagnose and verify the issues that plague it. Sometimes it's a poor mold design, inferior materials, or a substandard tool build that's to blame; other times it’s a processing issue.

Whatever the cause, our goal in a transfer program is two-fold: Make the necessary repairs or replacement of tooling components quickly and re-qualify the tools to get them back into production with minimal disruption to our customers' delivery schedules; and Craft a game plan to provide the lowest total cost of ownership over the remaining lifetime of the program. Of course, each case is unique, but our recommendations will always have the customer’s best interest in mind. Sometimes their money is better spent to repair the existing mold, other times a new mold with our guaranteed tool life and part quality may make more economic sense, all things considered.

We know customers only transfer existing programs when unexpected circumstances force them to.  At Matrix Plastic Products, we stand behind our reputation for quality, honesty, and a commitment to help make the transition as painless and stress-free as possible. We want our customers to feel that, in the long-term, bringing their program to Matrix was the best move they could have made.

 

Proud members of:

TMA - the Technology & Manufacturing AssociationMAPPAMBA Round Bannerima logo

Stay Connected!