Depending on the chemical structure polyester can be a thermoplastic or thermoset, however the most common polyesters are thermoplastics.[1]
Might want to have a read of this Jim, written by John Jowdy recently
It's time to correct misconceptions about the nature of the equipment we roll down the lanes
How often have you heard bowlers, professionals and amateurs alike, refer to their equipment as "plastic" or "resin"? Better yet, how many times did you hear the word "plastic ball" in the recent ESPN telecast of the PBA Mark Roth Plastic Ball Championship.
In point of fact, these are misrepresented and distorted words used to describe bowling balls. The use of the words to describe bowling balls is mistakenly applied not only by uninformed bowlers but also by ball reps on the PBA tour, manufacturers sales reps, pro shop operators who place orders for these balls, and WORST of all, by TV analysts who are supposedly " in the know".
Manufacturers classify bowling balls as polyester or urethane. Somewhere, somehow, outside the manufacturing industry, "resin" and "plastic" surfaced as the proper lingo.
Interestingly, the usage of "plastic" is not only misused by bowlers, but is never corrected by those who should know better, including me.
The term "plastic" has been bandied about by professional bowlers, pro shop operators, bowling writers, sales representatives, and ball reps on the professional tours. It is improperly employed by analysts on television shows who unabashedly refer to a bowler shooting at a 10-pin with a plastic ball.
The word plastic, rather than polyester, has crept into a number of manufacturers' vernaculars. This is, perhaps, due to the continuous and prolonged use of the word "plastic" among bowling participants.
Before proceeding any further, let's examine the origin and source of this misinformation. Webster's New World Dictionary defines resin as " a synthetic, usually resinous substance, which, when subjected to heat and pressure, can be cast, pressed, extruded, or molded into various shapes." Again, referring to Mr. Webster, synthetic is defined as "compounds produced by chemical reaction in a laboratory as opposed to those of natural origin".
Furthermore, dictionaries define the plastic as "any of various nonmetallic compounds, synthetically produced, which can be molded or hardened for commercial use."
Suffice to say, the term "plastic" renders ALL bowling balls as synthetic products. Consequently, "plastic" not only covers polyester balls, but also includes urethane.
EVERY ball manufactured and marketed in the past 50 or 60 years has been formulated from a synthetic substance, including many of the so-called rubber balls dating back to the 40's and 50's.
As a matter of fact, during World War II, when the demand for pure rubber products exceeded the natural output, rubber balls, as well as automobile tires, were created with plastic materials. Hence, the word "synthetic" is the most appropriate characterization of any and all bowling balls today.
We can say that while all bowling balls are synthetic, some are polyester resin and some are urethane resin.
During the late 50's, Brunswick and Columbia produced the original synthetic balls in various colors. They were familiarly referred to as "plastic" balls and, although plastic covered a multitude of man-made materials, the synthetic substance used by Brunswick and Columbia at that time was, and continues to be polyester resin.
In the late 70's, AMF revolutionized the bowling ball market with the introduction of the Angle, a ball produced from urethane, one of he most intricate and sophisticated resins on the market. Urethane, a rapid curing resin, is an extremely rigid material, yet possesses unbelievable traction on the lanes. The angle dominated the pro tour; that is, until all other manufactures jumped on the urethane bandwagon.
In the late 80's, Steve Cooper, a former professional bowler from Southern California, produced the Excalibur, a urethane ball concocted with various additives that created an even greater "tacky" feel that helped the ball to increase its grabbing effect on the lanes.
The incredible hooking action and explosiveness of Cooper's missile sent manufacturers scurrying throughout the country, seeking advice from chemical manufacturers for similar resulting materials.
Cooper's ball, displaying extraordinary movement and entry to the pocket, earned the nickname of "cheater ball" from professional bowlers. The combined various materials in these type balls have been categorized as "reactive" resins, thus providing bowlers with more sophisticate weapons.
As the years went by, urethane balls have been customized with glass particles and various other adhesive concoctions. Such foreign substances, heretofore banned by USBC, (formerly ABC/WIBC) regulations, have somehow managed to skirt the rules and infiltrate the manufacture of urethane balls. The new ingredients serve to put more "teeth" into the balls as they make contact with the lanes.
At any rate, the terms "resin" and plastic" balls have been technically misleading. Consequently, after so many years of erroneous expression, it seems reasonable to set the record straight by defining a ball as polyester or urethane.
The proliferation of sophisticated weapons has been bewildering, not only for competent professional bowlers, ball reps, and drillers, but more importantly, for amateurs who attempt to emulate PBA players.
While new materials in ball surfaces and sophisticated core placements continue to aid higher-average players, beginners and recreational bowlers can be better served with less potent equipment. This is particularly advantageous for female bowlers who are afforded the opportunity to choose from a large assortment of brilliant colors and weights manufactured from polyester resins.
Most astute pro shop operators prefer to cultivate long-term relationships with their clientele by recommending bowling balls best suited for beginners and less proficient bowlers. Unfortunately, a few uncaring drillers attempt to sell this segment of the bowling population pricier, unmanageable equipment in order to net a few extra bucks.
Fortunately, the greatest majority of IBPSIA (International Bowling Pro Shop Instructors Association) operators take great pride in their craft and, rather than seek higher profits, they make the customer's satisfaction uppermost in the long run.
Consequently, as suggested in my two books, Bowling Execution, and Bowling Execution, Second Edition, I advise bowlers, serious or recreational, to seek out pro shops displaying the IBPSIA logo. IBPSIA is an organization dedicated to its profession and skillfully trained to meet bowler's needs.
Perhaps the only thing most agree on is the employment of a polyester bowling ball (referred to as plastic) when addressing 10-pins or 7- pins. While I am in accord with this philosophy, I further recommend polyester balls for any and ALL single pin conversions.
I further encourage delivering straight shots at all two-pin spares other than 2-8's, 3-9's or spares that presents "sleepers". These are two-pin spares where one pin is directly behind another. These spares can be more easily converted with a slight hook into the front pin.
Despite the advantages of modern supercharged balls, bowlers noted for their high-revving shots have abandoned urethane in favor of polyester balls when lanes dry out and present uncontrollable conditions. However, this is more the exception than the rule.
When should less proficient bowlers consider urethane equipment? These are two requisites that bowlers must abide by:
1. They must be able to approach the foul line in proper balance.
2. They must develop a swing that enables them to deliver the ball freely with proper direction.
These are the initial steps for bowlers to advance their skills. If they cam master these two factors, they will be prepared to progress to the more sophisticated tools of the trade.
Additionally, they and all participants in our great game, should be able to distinguish the two most underused words in bowling vernacular, POLYESTER and URETHANE from the misused words, plastic and resin.