best practices
Understanding the Effect of Pressure Losses on Injection Molded Parts
The compressibility of plastics as a class of materials means the pressure punched into the machine control and the pressure the melt experiences at the end of fill within the mold will be very different. What does this difference mean for process consistency and part quality?
Fundamentals of Polyethylene – Part 6: PE Performance
Don’t assume you know everything there is to know about PE because it’s been around so long. Here is yet another example of how the performance of PE is influenced by molecular weight and density.
Read MoreFundamentals of Polyethylene – Part 5: Metallocenes
How the development of new catalysts—notably metallocenes—paved the way for the development of material grades never before possible.
Read MorePolyethylene Fundamentals – Part 4: Failed HDPE Case Study
Injection molders of small fuel tanks learned the hard way that a very small difference in density — 0.6% — could make a large difference in PE stress-crack resistance.
Read MoreFundamentals of Polyethylene – Part 3: Field Failures
Polyethylene parts can fail when an inappropriate density is selected. Let’s look at some examples and examine what happened and why.
Read MoreAPR Expands Design Guide for Plastics Recyclability With Polypropylene Categories
Six new packaging categories will be eligible for third-party validation of compatibility with North American recycling programs.
Read MoreWhere and How to Vent Injection Molds: Part 3
Questioning several “rules of thumb” about venting injection molds.
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Improve Production Rates Via Screw Design — Barrier vs. General Purpose vs. Melt Uniformity
I’m looking for a few good molders to help trial a new screw design, and share data and results for a future article to prove the benefits of a melt uniformity screw.
John Bozzelli
Back to Basics on Mold Venting (Part 2: Shape, Dimensions, Details)
Here’s how to get the most out of your stationary mold vents.
Read MoreUltrasonic Welding: Tips, Techniques, and Troubleshooting
In this collection of content, we provide expert advice on welding from some of the leading authorities in the field, with tips on such matters as controls, as well as insights on how to solve common problems in welding.
Read MoreASTM Standard To Support Sustainable Plastics
Plastics committee is developing a standard to support a circular economy for plastics.
Read MoreBack to Basics on Mold Venting (Part 1)
Here’s what you need to know to improve the quality of your parts and to protect your molds.
Read MoreHow to Achieve Simulation Success in Molding, Part 3: Inputs, Reports and the Analyst
Ultimately the success of this virtual, digital software falls to the real-world, analog humans requesting and completing the analysis.
Read MoreUsing Data to Pinpoint Cosmetic Defect Causes in Injection Molded Parts
Taking a step back and identifying the root cause of a cosmetic flaw can help molders focus on what corrective actions need to be taken.
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Avoiding Common Cosmetic Defects in Molded Parts
Identify familiar flaws and then work to eliminate them with these mold and part design tips, and process considerations.
How to Configure Your Twin-Screw Extruder: Part 3
The melting mechanism in a twin-screw extruder is quite different from that of a single screw. Design of the melting section affects how the material is melted, as well as melt temperature and quality.
Read MoreRoll Cooling: Understand the Three Heat-Transfer Processes
Designing cooling rolls is complex, tedious and requires a lot of inputs. Getting it wrong may have a dramatic impact on productivity.
Read MoreFive Quick Steps Toward Better Blending
Rising costs of resins and additives, along with higher demands for quality and use of regrind, place a premium on proficient blending. Here are some steps to get you there.
Read MoreGot Streaks or Black Specs? Here’s How to Find and Fix Them
Determining the source of streaking or contamination in your molded parts is a critical step in perfecting your purging procedures ultimately saving you time and money.
Read MoreEnsuring Repeatability: The Key to Effective Injection Molding Automation
One of automation’s key promises is repeatability: the same movement to the same location, time and time again. But to achieve that, all elements involved — robot, machine, EOAT, mold — must be in and stay in alignment.
Read MoreThe Importance of Hot Nozzle-Tip Mating Against a Cold Sprue Bushing
Done improperly, the result is a cold slug in the nozzle/sprue and a production stop. But there is a better way.
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Is There a More Accurate Means to Calculate Tonnage?
Molders have long used the projected area of the parts and runner to guesstimate how much tonnage is required to mold a part without flash, but there’s a more precise methodology.
Suhas Kulkarni
Founder & President, Fimtech
Getting into Plastics Additive Manufacturing? Avoid these Six Common Errors
There are a lot of 3D printing technologies out there, and it’s not uncommon for processors new to additive manufacturing to get tripped up. Here are some typical snafus, along with advice on how to avoid them before you start making parts.
Read MoreWhy Shoulder Bolts Are Too Important to Ignore (Part 2)
Follow these tips and tricks for a better design.
Read MoreWhy Shoulder Bolts Are Too Important to Ignore (Part 1)
These humble but essential fasteners used in injection molds are known by various names and used for a number of purposes.
Read MoreKnow Your Options in Injection Machine Nozzles
Improvements in nozzle design in recent years overcome some of the limitations of previous filter, mixing, and shut-off nozzles.
Read MoreBozzelli’s Guide To Specifying a Dryer
Here's a list of 17 things to do when looking for new drying equipment.
Read MoreRun Lots of Colors? Time to Consider a Commercial Purging Compound
Processors who use commercial purging compounds will see a reduction in scrap levels, machine downtime and overall cost.
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