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What April Showers, May Flowers, and Bluebirds Can Teach Us about Extrusion

Image: Rabbitti/Adobe Stock bluebird
It’s all about planning, and learning that the unpleasant now may breed success later on, says extrusion guru Allan Griff.

The first written record of April showers comes from Chaucer, way back around 1395. Not read much in his time, as printing wasn’t even invented yet. The connection to May flowers was used in 1557 by English farmer-poet Thomas Tusser. Very fast forward to 1886 for the proverb that April showers bring May flowers. We understood by then that plants need water (and carbon dioxide) to convert to their green and flowery parts. But the best-known connection is the 1921 song by DeSylva (words) and Silvers (melody), made popular by Al Jolson, who sang it in a now-forgotten Broadway musical called Bombo:

“Though April showers may come your way, they bring the flowers that bloom in May, …. so, keep on looking for a bluebird and listening for his song, whenever April showers come along!"

I didn’t know what a bluebird looks like, but I do now (see picture above)! If you want to hear one, try this link.

So, what on Earth does any of this have to do with extrusion?

First of all, it teaches the lesson that the unpleasant now may breed success later on. Not always true, of course, but it does apply to installation, and also to learning about the materials you use. It also says to plan ahead for when we do have flowers by estimating how much we want to make per hour or year of what products before buying or assigning materials and machinery.

Another lesson, in reverse: Do not assume that because oil or natural gas prices go up or down, resin prices will follow. Some salespeople would like you to think so, but there does not have to be a direct relationship. Most oil/gas is not used for plastics, and there are costs to refining — separating the components of — oil, making monomers, and then making polymers from monomers. A barrel of oil contains 42 US gallons, or 159 liters, so at $60/barrel that comes out to $0.377/liter — or at a density of 1 g/cc, around 17 cents/pound — well below the current price for virgin anything. And one other factor makes the connection to oil prices even fuzzier — big refiners usually don’t buy oil at market price, but have their own wells and contracts.

In the real world, the May-flowering plants in most of North America and Europe were planted the previous year and overwintered, or else started indoors. In other words, planning was involved. We can do better than rain, too, by using additives in appropriate amounts: Slip and anti-stat agents, antioxidants and stabilizers, fillers and reinforcers, and, like the flowers, color.

Production is a real-world activity, and purchases may have delivery conditions ­— how much of what by when and delivered where? And what happens if it doesn’t get there by then? Some contracts are not so specific, as they leave wiggle room based on the relationship and, sometimes, the competition and quality of the product.

Commitment to quality may be very important, but it has to be defined. Gels and other particles can be minimized by fine screening and management of melt temperature and thermal stability. Reducing thickness variation may avoid product failure and may cost less if thickness aim can be lower. That may justify continuous thickness monitoring to gain a sales advantage.

As to seasonality, with a few notable exceptions like fire-resistant PVC Christmas trees (which I worked on back in 1963), we want to use our equipment as many hours a year as practical. So, we have a gardener’s problem — finding flowers that bloom at other times than May. That’s what fall chrysanthemums are for, or early spring fruit-tree blossoms, but with extrusion we want products needed all year round. Fortunately, plastics have a longer shelf life than flowers, but storage space and deliveries need planning, too.

Last and not least, the invocation of water as life-giving reminds me that plastics are all the more needed as our myth-informed detractors keep pushing paper as “natural.” The viruses and bacteria that can kill us also are natural. Our extruded products are nontoxic and life-giving in many ways, as are the April showers. The plastophobia is not “crazy” nor activist inventions, but based on our child-learned need for miracles, which is denied by our sciences of chemistry and physics. However, we grown-ups can understand and utilize science to our benefit, and still find ways to manage our need for miracles.


About the author

Allan Griff is a veteran extrusion engineer, starting out in tech service for a major resin supplier, and working on his own now for many years as a consultant, expert witness in law cases, and especially as an educator via webinars and seminars, both public and in-house, and now in his new audiovisual version. He wrote Plastics Extrusion Technology, the first practical extrusion book in the United States, as well as the Plastics Extrusion Operating Manual, updated almost every year, and available in Spanish and French as well as English. Find out more on his website,, or e-mail him at [email protected].

No live seminars planned in the near future, or maybe ever, as his virtual audiovisual seminar is even better than live, says Griff. No travel, no waiting for live dates, same PowerPoint slides but with audio explanations and a written guide. Watch at your own pace; group attendance is offered for a single price, including the right to ask questions and get thorough answers by e-mail. Call 301/758-7788 or e-mail [email protected] for more info.

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