We are not in the USA but close enough that the locals here in Aruba have definitely been infected. Finally we have reached the part of the world that doesn’t do metric and prefers to fight with the mathematical chaos that they call U.S. customary units.
Yesterday we broke our two millimeter drill so tried to buy a new one at the hardware store. They didn’t have any but, after finding their conversion table, they told us what we really needed was a 5/64 inch bit. The mathematics behind that conversion is 5 / 64 inch x 25.4 mm / inch = 1.984 mm – which is close enough.
And if you were thinking a 4mm drill would be 10/64 inch then you would be wrong as it is 5/32 inch and of course a 3mm is an 1/8 inch – although it isn’t really as an 1/8 inch is 3.175 mm. My head hurts.
And now we have a pump with a 3/8 FPT thread on the input – which we need to convert to a 1/2 inch tube – and a 3/8 OD output which we can connect some tube to. We thought Google could help with all this and received the answer
Tube is measured by outside diameter, pipe is measured by inside diameter. There is often confusion as to which size die the customer actually needs – Pipe Size or Tubing Size. Keep in mind that pipe size refers to a nominal – not actual – insidepipe diameter.
Luckily they sell rum relatively cheaply on the island