DIYbanter - Grinding wheels

On 16 Jan 2006 07:45:57 -0800, "Er Principe"
wrote:
I'd like to buy a set of good grinding wheels of various grains (from
coarse to extra fine), for my woodworking tools

I don't believe this would really improve things. There's scope for
having lots of different manual stones (I polish Japanese swords - I
have about 15 stones) but for a powered wheel it's more about getting
the right type of machine. If there is any variation in stone type, it's
likely to involve a different machine (size, speed or other arrangement)
rather than just swapping a stone onto the same spindle.

A small 3000 rpm machine with a fine stone is cheap and will sharpen
metalworking tools. It's pretty much useless for woodworking though
(although we all have a few metal tools too)

A better 3000rpm (like a Creusen) can be obtained for a reasonable price
and with a wide soft stone that's more useful for woodworking. However
it's still too fast for hand tools.

Rather better is a 1400 rpm motor and a good stone (Creusen again) This
is a good choice for HSS turning tools, but it's still too fast for hand
tools.

The only half-decent powered option for woodworking hand tools is a
large slow water-cooled wheel. You can get these as belt-driven single
wheel machines (Scan) or more noisily as worm-driven Chinese import
machines with a tiny fast wheel on one end and a water wheel at right
angles to it. These cost 30 quid with a poor coarse wheel on them, 100
quid with a decent wheel.

You'll probably want a powered honing wheel too - probably a leather
powerstrop or similar. These rotate away from you, so they don't need
the same rests and guarding as an abrasive wheel. It's a good gadget to
build yourself from a surplus motor, not having to buy a grinder. It's
certainly awkward to arrange from a grinder, as you'd have to arrange
access round the back - again we're back to needing different machines
for different grades of "stone", not just swapping them.

One thing you can't do with a powered stone is to get the equivalent of
my main manual sharpening stone, a 1000 grit waterstone. This is enough
for everyday sharpening (not just honing) yet it leaves a usable edge
directly (I then use 4000 and 10000 grit stones). You can't do this
grade on any powered wheel - a horizontal axis wheel would need to be
about 3' diameter and the available vertical axis machines are a
nightmare for hollowing with a soft waterstone in them. Getting a
smoothing plane iron flat involves so much flattening that you see very
heavy stone consumption.

There's also the issue of needing to "true" abrasivewheels after they're
mounted. If you did change wheels regularly, you'd have to be doing a
lot of truing to get good enough performance for fine sharpening of
plane irons.

Quite honestly I just don't see the need for power sharpening small hand
tools (although I wouldn't be without for HSS woodturning chisels)

Do you know if is it possible to find good grinding wheels and machines
at a nice price buying from such countries [indian and chinese ] ?

Not IMHE. I'm sure they could make them, but as yet there isn't a demand
to cause it.