"DIYGUY" wrote in message
oups.com...
... answer me this question. If a caster wheel is rated at a load
carrying capacity (which it is) how is the rating determined? I have a
600# tool I want to put on casters. Does each caster have to be rated
at 600# or can I get four casters, one on each corner, that are each
rated at 150# (or more) load bearing capacity?\

Well, we could get into center-of-gravity calculations and draw free-body
diagrams. But I don't think that's what you asked. :-)

Most of the answers given already are correct. Its a valid engineering
approximation to divide 600 lb across the four wheels for most stationary
tools. However, don't just use the weight as a factor. Caster material and
minimum caster diameter are just as important. You can get a lot of casters
that will do the minimum load of 150#, but I sure wouldn't put a stationary
tool on 2 inch soft neoprene casters. For one thing, cheap soft casters
will tend to get flat spots holding up a heavy stationary machine. I'd say
you probably should not have anything less than 3 inch diameter wheels. Go
with industrial grade casters, too. That rules out most of the things you
find in Lowe's.

For a retail outlet source, I think the heavy duty casters sold by Woodcraft
are more along the lines of what you would be looking for.

When you calculate height, remember to look at the actual height of the
overall caster, not the nominal diameter of the wheel.

Bob