Question

I have obtained an an antique Philip Harris balance scale in good, but condition aside from a lot of corrosion on the brass. I can't find a model number on it and am not sure of it's actual age, but I am guessing 1950's. It has a chain-dial on it, which is something that I'm not familiar with. I've not been able to figure out how to actually use the chain-dial or indeed any information on them. In cleaning up the scale I found that the guide for the plumb line was not correctly attached so it's possible that the chain-dial isn't attached right either.

Can anyone explain in detail how the chain-dial is used or direct me to some documentation or textbook resource on using a scale of this nature.

Answer 1

The chain-dial on a balance scale allows for fine adjustments to precisely determine the mass of an object by adding or subtracting very small amounts of mass to achieve an exact balance.

Step-by-step explanation:

The chain-dial on a balance scale is a feature that allows for fine adjustments to determine the mass of an object with greater precision. The balance scale works by placing the object of unknown mass in one pan and standard masses in the other pan.

Once the bar connecting the two pans is horizontal, indicating equal masses, the chain-dial can be used to make minor adjustments until the balance is exact. It functions by adding or subtracting a very small mass, typically much less than one gram, which helps readjust the balance without having to add or remove standard mass pieces. So, though a typical mechanical balance scale may only read mass to the nearest tenth of a gram, the chain-dial feature allows for more refined measurement.

However, if the plumb line guide on your balance is not correctly attached, it could affect the accuracy of your measurements, and correcting that should be a priority.