There are many variables concerning what is loosely termed as a "weight count". In this publication our goal is to pursue vigorously every possible variable that could cause the "weight-count" of a box of thermoformed product to not be equal to the specified number of pieces for a specific type of product. It is not our goal to confuse anyone, but we will accept this as a delightful bonus. Note that this publication is the result of literally billions of hours of research, and almost no forethought.

Variation vs. Constant

Variation describes that which may change and constant describes the opposite. During a weight count procedure it is best to eliminate as many variables as possible to ensure a proper Standard Operating Procedure (SOP). In this publication we wish to examine every possible variable, and the impact that it may have on a successful weight count.


Tape, like other objects, has weight. When a thermoformed product packer makes the mistake of taping a weight-count box closed before weighing the box, the weight of the ruined box will not be perfectly accurate. We suggest that all the parts that are in the box be repacked into an un-ruined box and that the ruined box be burned. To test our hypothysis, we weighed a thousand boxes before taping them, and then re-weighed each box after it was ruined. What we found is that some research is so boring and useless that it is not worthwhile.


Labels, like other objects, have weight. If a weight count is done without a label on the box, then all subsequent boxes must not have a label on them while being weighed. The only alternative is to weigh the label by itself prior to placing it on the box, then subtracting the weight of the label from the weight that is given for the box to match to the weight count.

Film Variance

One roll of film may vary significantly from another roll in thickness, even if both rolls are labeled to be the same guage. Therefore, a new weight count procedure should be started every time a roll of film is changed on the machine. If a box contains thermoformed product from two different rolls of film, then that box should be handcounted.

Our research shows that the film on the far side of a roll can weigh significantly different from that of the near side. To perform this research we counted 200 parts from the three cavities of the near side of a six-up stacker, and did the same thing with the far side. We put 200 "near-side" products in one box, and put 200 "far-side" products in an equally raggety box with approximately the same amount of old labels and tape on each one. One box weighed 22.25 and the other weighed 23.15! Almost a pound difference! This shows how even the smallest variable can be muliplied by hundreds when concerning hundreds of product parts.


A used box with old tape and labels attached will obviously not weigh exactly the same as a new box. Because of this a new weight count procedure must be started anytime a thermoformed product packer changes from used boxes to new boxes. A good thermoformed product packer will also start a new weight count procedure if the number of labels on a used box is different from that of the prior used box. Also if the amount of tape on a used box is different, this must be accounted for also.


Scales are not generally all calibrated at the exact same moment in time, and may lose calibration at different rates anyway, given that they exist in an imperfect world. Therefore, if a packer of thermoformed product changes the scale they are using partway into a box, then they must hand-count that box and then perform a new weight count procedure immediately. Also a scale must be exactly level to be somewhat accurate. A PACKER OF THERMOFORMED PRODUCT SHOULD NOT TRUST ANY SCALE BEFORE MEASURING EACH LEG OF THE SCALE WITH A COMPANY-CERTIFIED SIX INCH RULER AND VERIFYING THAT THEY ARE ALL OF THE EXACT SAME DISTANCE!!!


Fans should not be allowed in the vacinity of an accurate thermoformed product packer. If in the process of packing thermoformed product, you should start to feel faint, you should contact your supervisor and let them know that to you, accuracy is more important than life itself, and that if you die of heat exhaustion, that it will have been for an important cause. Accuracy.


Dividers are sheets of cardboard that separate layers of thermoformed product. When two dividers have the same width and length, but have different thicknesses, they will mostly likely have different weight. Therefore an accuate thermoformed product packer will measure the thickness of each divider before use with a micrometer. The length and width should be measured also, since even a minor change in either one could cause insignificant results.


Humidity is the amount of water in the air. When the air is humid, the water in the air may have a tendency to seep into some pourus objects, such as boxes. This will cause a somewhat unimportant change in the weight of a box. Because of this, it is our recommendation that packers of thermoformed product keep at their stations a device for measuring humidity. The packer should check the device once every 60 seconds. If any change is detected then the packer must begin a new weight count procedure.


Insects, like most organisms, have weight. Think about it. Since insects tend to fly about randomly, it is certainly possible that if a packer of thermoformed product did a weight count with only 52 flying insects contained in a box, and later a box is packed with 53 flying insects, that the box with 53 flying insects may not have enough thermoformed products contained within, although it will have one extra, delicious flying insect, and perhaps the customer will be pleased just the same. Do not just assume that the customer has the same taste for flying insects as you, please contact them in advance.

In Conclusion

As you can see there are many variables when performing a weight count procedure. Our initial conclusion was that there were only two ways to have a truly accurate count of thermoformed products:
1. Count out all parts by hand.
2. Be anal.

After further research we realized that there was really only one way, since these are the same thing.

Appendix: Human Error

As if there were any other kind. For some reason only humans will sacrifice all common sense to impress their friends. This is sad indeed, because our studies show that common sense is the greatest variable of all. To conduct our research, we asked 1,386 people the following questions:

1. If you had to count 1,386 people, would you do it by weighing a sample of 100 people, dividing the weight by 100 to find the weight per person (x), and then taking the weight of all the people and dividing by x?

2. If you did, would it be accurate?

Do I look stupid?

Wait -- Don't answer that!!!


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