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Posted to rec.crafts.woodturning
Mark Fitzsimmons
 
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Default Very Newbie Question


mac davis wrote:
Honing is only effective if the tool is pretty sharp already.. otherwise, you're
not honing an edge, you're polishing it and it looks pretty, but is also pretty
dull...


Yeah, what he said. When you look at the edge in with light shining
from behind your head, and you can see a shiny metal line where the
edge is, that means it's dull, because the light is reflecting off a
radius. When it's really sharp, the edge is so fine you should be hard
pressed to see any line of reflected light on the edge.

I use 60 grit wheels only to really change the shape of a tool or grind
back a long way from a bad chip on the tool. Grinding with 60 grit can
require a lot of honing with finer stones to smooth out the ridges and
valleys of the edge left by the wheel. That said, a light touch and
smoothing the wheel with a dresser can still produce great edges for
lots of roughing work, especially for scrapers, where many people love
to keep the burr on the edge. Once you've mastered the 60 grit wheel
and wish it were sharper, you might try 100 or 120.

I do it both ways (burr/ no burr) depending on the wood. For really
punky wood that's spalted, you almost have to scrape to get the best
finish before you sand. Trying to cut punky wood gives more tear outs
than a razor sharp scraper, no burr, just honed to the point you can
shave hairs off your arm.

In fact, until you can master cutting methods, you'll probably get your
cleanest surface (by which I mean not just smooth, but a fair line on
the profile that doesn't have bumps and valleys) with a razor sharp
scraper. Often this need -- to have a fair line on profile -- trumps
smooth surface and minimal sanding.

It's hard to cut a fair curve with a gouge, even when it's sharp, and
takes a lot of practice. I've been turning 24 years and still have to
clean up some gouge work with a good scraper now and then. It gets
harder as the diameter of the wood gets larger, since it takes longer
for the wood to come around, and you have to remain stationary longer.