Efficient Inspection & Weigh-In: can 2 scales be used?

[birddog]

I'm adding an open division to our racing this year and I want to be sure we can efficiently handle the extra volume of cars on inspection night. We conduct our inspections the night before the race.

We budget 6:30pm to 8pm to get inspection of 60 cars done. During the peak window, things can get backed up a bit.

We use a scale that is accurate to .1 oz, so we don't need to worry about getting weights accurate to within .01oz (which adds time as we've learned in the past).

We can easily add another inspection box and more volunteers to inspect, to create 2 or 3 inspection lines. However, I'm concerned about the idea of using 2 different scales. Right now we have one single official scale and it is the master. Everyone gets weighed on that scale. We do offer other scales that entrants can test their car on before they come to the official inspection line. I think adding a 2nd official scale may put efficiency ahead of fairness. I don't want to do that.

Thoughts?

[FatSebastian]

I'm adding an open division... and I want to be sure we can efficiently handle the extra volume of cars on inspection night.

If the open-division entries only race against each other, then open entries should be able to use their own separately dedicated "official scale" without impacting perceptions of fairness.

I think adding a 2nd official scale may put efficiency ahead of fairness. I don't want to do that.

A single scale can become uncalibrated with continuing use and other environmental factors (jarring, hysteresis, temperature changes, etc.). This means that the numbers coming out of a scale at the beginning of the weigh-in period can be different for the same car weighed at the end of the weigh-in period. To really maintain fairness, the official scale needs to be occasionally checked and recalibrated / zeroed, but during the chaos of check-in this is sometimes overlooked. Or worse, many operators don't know how to recalibrate the official scale or have the proper weights to do so.

Therefore, toward the question of fairness, one could argue that simultaneously using two scales of identical make, properly calibrated and maintained, may be more fair than one "official" scale that is never calibrated and maintained.

[Lead Reindeer]

With a little statistics, you can prove that the 2 scales will be indistinguishable from each other. Just take good care of your calibration weight and make sure to use it on both scales.

Besides if the scale is accurate to the tenth of a gram, it is likely that some folks are racing cars that are 5.04oz, and some racing 4.96oz cars. The builder's preferences probably make more of a difference than your scales will, especially if you follow Sebastian's suggestions.

Good luck!