Workshop - I purchased a 1.2 metre long steel ruler a while back, figuring that it would be more accurate than a tape measure for laying out the leadlight for our house. It took me a while to twig as to why my leadlight cartoon wasn’t square. After exhausting every other possibility I put the ruler against a steel beam and sure enough, it bowed by a couple of millimetres in the middle - enough to make a precise drawing imprecise.
I took the ruler back to the shop, who were disbelieving until I held it against a flat steel shop fitting. They were even more astounded to discover that every long ruler in their shop was the same.
The solution was to buy a much heavier aluminium number as I realised that I not only wanted a measuring device but also a straight edge.
After this I checked all my rulers, tape measures and machines, only to find that a metre isn’t always a metre. The most extreme variation related to the clip movement on some tapes which could account for a variation of +/- 3mm depending on whether you were measuring by pulling or pushing the tape.
As a result of this discovery I now try to use the same measuring device throughout a project. I figure that even if it’s slightly incorrect, it will at least be consistent. One day, if I ever find the time, I’ll calibrate the whole workshop.
Thought - We all have some point of reference against which we measure ourselves, be it subconsciously or not. For some of us it is the trends and views of the world around us, indeed that is the default “standard”. For others, it is God's fat letter. When you have a moment, consider Proverbs 20:9-11 .
Against what, or who, do you calibrate yourself?
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