Broken planes is a subject that comes up often in the
Facebook Unplugged Woodworking group.
Stripped threads are common on wooden planes that
use threaded arms to position a fence. They usually break next to the armís foot
as that is where the fence is most often needed.
This is my example, it
will be my repair experiment. Years ago I demoted it
to a kerfing plane by replacing both skates with a
blade cut from an old rip saw. I screwed an inch and
a half spacer block on the fence to skip over the
defective threads, which worked, but is awkward and
heavy. Iím going to simply cut out the defective
section, which will shorten the range of the plane,
but who plows grooves six inches out anyway.
These are the two
threaded arms. Each was made from a single piece of
wood with a 3/4″ O. D. threaded section. The
challenge is to securely and accurately splice the
amputated threads back on the foot.
So my plan removes the
stripped part, then makes a half inch round tenon on
the end of the good threaded rod, with a matching
half inch mortise in the foot. The two parts are
reassembled with a 1/4-20 threaded steel rod pulling
them together, I think it will be at least as strong
as the original solid wood part.
Most of the work was
done on my Delta DP-300 drill press on which I have
carefully aligned the press table square to the
The first task was to
make a fixture to hold the threaded arm accurately
aligned with my drill chuck. I had to file the hole
in the drill press table a bit to get the threaded
arm to pass up through easily from the bottom.
To make the alignment
fixture, I screwed a bit of 2◊4 to a piece of scrap,
clamped that to the press table, then ran a 3/4 inch
Forstner bit down as far as it would go, I had to
finish the bore with a longer spade bit. I removed
the drilled 2◊4, cut a slot on the table saw, then
installed two screws to help clamp the threaded arm
in place. It did take a small amount of sanding to
get the threaded arm to pass through.