robgraham wrote:
Oh dear, sweet naivity strikes again ! I changed the the wheels on my
6" machine some years ago and never thought about it any more than
being a standard maintenance task. What skill is required of an
'expert' and what should I have attempted to do ?

And what is a 'buy and spew grind stone '?

First, a grind stone is on a mission to re-model your face if not
installed correctly. As Andrew mentions below, it is a skilled job to
mount a new stone.

There have been threads about doing your own gas work in the past and I
agree, that if you feel competent, then go ahead and do it.
When it comes to mounting a new wheel on a grind stone, I would favour a
lot of caution, unless you have had some training of how to do it and
the dangers that can come out of this simple exercise.
Over tighten the nut that holds the wheel to the shaft and you can
expect an exploding wheel pretty soon and it will not leave a pretty
face either.

I have been in engineering for well over 40 years and I remember seeing
a grind stone wheel bursts and it went clean through a brick wall. On
the gory side, I have a cousin that saw a lathe operator picked up and
dashed to death by the lathe he made his money on. You takes your chances.

Second. Buy and spew is an acronyms for a well known DIY store where the
folk that work there wear red or orange pinnies (dependant on the size
of the store).
They sell cheap tools for the DIYer. That is why I stated that if the
grind stone wants a new wheel, then the best bet is to buy one of
theirs. At least then, you can get compensation from them if anything
goes wrong from a badly fitted wheel. (I have one of their cheap ones
and it is fine for everyday use)

Dave