I hate metric. I can’t visualise a metric size and have to convert to imperial to get an idea of the size. 32mm means nothing to me until I recall it’s close to 1 ¼”. Same with 25mm and 100mm. Look at plywood: used to be 8’ x 4’. Now it’s a metric size. 3m x 2m perhaps? No, it’s a conversion of 8’ x 4’ (2440mm x 1200mm). And the thickness mirrors the original imperial sizes.
Any mistakes I make when working in wood or steel are invariably when using metric. My favourite mistake is to cut a piece of wood at, say, 1.2m. Out comes the tape – one metre, plus two, cut …. oh dear, that was 1.02 not 1.20.
And the bolt sizes are a nightmare, with up to four different pitches per diameter. The French seem to follow close to imperial sizes on their vehicles with regard to spanner sizes (eg 13mm, 16mm etc) but the Japanese seem to love smaller sizes (10mm, 12mm)
Not forgetting the crafty and unnecessary odd sizes used, presumably to force DIY’ers to go to the dealer. 18mm is a favourite (I use a whit spanner for that) and other sizes that don’t appear in a normal set of spanners or sockets, eg 15mm. There’s another oddball size where 15/16”AF seems to fit quite well.
Let’s go back to imperial!. Personally, I preferred the Whit and BSF threads to UNC / UNF and definitely when compared with metric. I agree though that the spanner sizes for Whit were a bit odd and often the bolt head was bigger than seemed necessary.
And I’ve not the slightest idea what I weigh in kilos (all I know is that 1,000kg is roughly a ton) and I happen to weigh 16 ½ St.
