Hi,

Does the group have any recommendations for a good spirit level, or
any tales of bad spirit levels best to avoid?

I ask because some years ago, I bought a 4' level from Screwfix. It
was a cheap, unbranded one. I have used it to put up shelves and
radiators without problems but the other week, I was trying to install
a door frame.

The level said the wall was plumb, the frame was plumb, and the door
was plumb. But the door would not close; it fouled against the frame.

Standing back, I noticed that the wall (and thus the frame) were not
truly vertical. I put a packer between the top of the frame and the
wall, which bought the frame true and the door shut perfectly.

I cannot understand why the level said the frame and wall were plumb
when they were not. Is it that they are less accurate when used
vertically than horizontal? Is it that unbranded ones are just less
accurate?

I notice that branded ones say they are accurate to 0.5mm/m but
unbranded ones keep quiet about their accuracy!

TIA