Vacuum cleaner hosing

Factual Questions
1

I was vacuuming/Hoovering the floor today and the nozzle came off the piece of flexible hose. The hose has a spiral wire along its length to stop it collapsing and I noticed the fitting has a thread in it. I tried to screw the fitting back on which at first didn’t work
because I didn’t realise it had a reverse ‘thread’. :smack:

The only other common thing I can think of that has a reverse thread are the pedals on a pushbike, so why would vacuum cleaner hosing also have a reverse thread rather than a normal thread?

2

To counteract coriolis effect? :smiley:

Seriously, I don’t think there is a reason aside from matching wire reinfoced hose that was already being made.

FWIW only one pedal on a bike typically has a left hand thread.

3

The fittings on propane tanks have left-hand threads.