My Stanley bench plane has plastic handles, so I don't have the ding
problem. However, I can see that the screw could be a problem for some
people. My solution requires a bit of work, but it should fix the
problem. First, take a piece of threaded rod from the hardware store
and cut off a piece about 1/2 to 3/4 inches long depending on the size
of you knob. Then you'll need one of the t-nuts or threaded inserts
which look like small nuts with spikes sticking out. You'll need to
unscrew the knob and hammer this nut into the wood in the bottom of the
knob until it is flush. Then simply screw the threaded rod into the
plane casting until it bottoms out, then screw on the knob. The t-nut
or threaded insert will act as a nut imbedded in the wood. You can
then just fill the hole in the top of the knob or ignore it. It sounds
complicated, but it really isn't. The one caveat is that you need to
make sure that when you buy the threaded rod and t-nut, it is the same
thread that is in the casting. This should do it, and I also recommend
the gloves in the previous post. I use them for chiseling and
hammering.