Shaping with a Router - MetosExpo - Free

Osage orange and its aliases
In this geographical area we have a wood the "old timers"
refe r to as bodock (pronounced with a long 0 and accented
on both syllables). These old timers value the wood for use as
fence posts because it won't succumb to termites and other
insects. Can you tell me anything about this wood and lend
advice about its use? -Donald E. Rutledge, Pulaski, Tenn.
Jon Arno replies: I'm almost certain the wood you are describing
is Osage orange, Maclura pomijera, a member of the
mulberry family, Moraceae. The name bodock sounds like a corruption
of bodarc (or bodark), which is, in turn, an Anglicized
form of the French term bois d'arc, meaning "wood of the bow."
When the early French settlers spread north from ew Orleans
they encountered the Osage Indians who used this species for
making their bows. This species was originally found only in the
south central United States, native to eastern Texas and parts of
Oklahoma, Arkansas and Louisiana. It is a small- to medium-size
tree, seldom growing more than 50 ft. tall, with gnarly, thornprotected
branches and large, round clusters of fruit about 4 in.
to 5 in. dia., which look like rough-skinned green oranges. Prior
to the introduction of barbed wire in 1874, Osage orange was
planted by farmers throughout the Midwest to create what were
descriptively referred to as "pig-tight" hedges, and now the tree
may be seen growing along fence rows as far north as Chicago
and east to the Atlantic seaboard.
With an average specific gravity of 0.76 (ovendry weight/green
volume), Osage orange is heavier and harder than any of our
native hickories, but like the hickories, it is extremely elastic and
resilient. The sapwood is white in color, while the heartwood is
a vivid yellow when freshly cut, aging over time to a warm, amber
gold. The pigment that gives Osage orange such a bright
color is water soluble, and by boiling the wood chips, the early
settlers were able to extract a dye for use with home-spun fabrics.
Since the wood of Osage orange can be confused with that
of black locust, Robinia pseudoacacia, the boiling of wood chips
serves a modern purpose in helping to separate these two species
because the yellow pigment in the latter is not easily dissolved
in water. Because Osage orange is a ring-porous wood, it
has a very attractive figure to complement its stuningly brilliant
color. It's definitely a real challenge to work, especially with
hand tools, but the results can be rewarding.
Uon Arno is a wood technologist and consultant in Schaumburg, Ill.]
Bandsaw-blade tracking problems
My 14-in. Delta bandsaw refuses to cut true when I run narrow
blades. To remedy this, I'd like to fi t the saw with Thompson
Model 236.2 conical blade guides. Do you know if this
mOdification will improve performance or correct blade drift?
-Roderick K Shaw, Jr., Tampa, Fla.
Mark Duginske replies: It can be velY disturbing when a
bandsaw will not cut in a straight line parallel with the saw table.
This phenomenon is called either lead or drift. There are a number
of possible causes for blade drift, but fortunately, the problem
is often remedied or is greatly decreased by tuning up the saw.
The best place to start is to properly align the bandsaw
wheels. The wheels should be in line with each other when the
blade is tensioned. This is particularly true of wider blades that
are normally used for making straight cuts. This is described in
detail in an article on bandsaw wheel alignment in Fine Woodworking
#75. Next, the guides and thrust bearings must be adjusted
accurately; this is a must for straight cutting. Both thrust
bearings have to support the back of the blade evenly. The distance
between the blade and the thrust bearing should be about
.015 in. or 1/64 in., except for the Vs-in. and 1/16-in. blade, which
should be against the bearing. Because the guide post rarely
goes straight up and down, the top guides and thrust bearing
should be readjusted every time the post is moved.
The blade guides are adjusted after the thrust bearings are set.
Metal guides should be adjusted until they're .004 in. (the thickness
of a dollar bill) away from the blade. If you've fitted your
bandsaw with non-metal guides that contain a dry lubricant,
such as Cool Blocks, the guides can be set in contact with the
blade. This decreases the tendency of the blade-especially
narrow blades-to deflect sideways, which can lead to blade
drift. Also, for straight cuts, make sure that the blade you are
using is sharp; use your dull blades for curved cuts.
Even with good guides and a carefully adjusted saw, you might
still experience some blade lead. First, it's best to work with the
lead rather than fight it. First, test the saw to see which way the
blade has a tendency to lead. Do this by putting a mark about Y2
in. from the edge on a 2-ft.-long board. Then, cut along this line
and feed the board about 12 in. into the blade. You may have to
angle the board slightly for the board to follow the line. After
cutting 12 in. along tl1e line, stop the saw, and keep the board at
the same angle that you fed the board to get a su-aight cut. Measure
this angle and set your bandsaw's rip fence to it.
[Mark Duginske is is a woodworker, teacher and author who
lives in Wausau, Wisc.]
Broken back due to short grain
While I was gluing the backrest/aim assembly atop the spindles
on a captain's chair I was building, the back cracked.
These breaks occured in the same place on each side: near the
ends of the middle segment of the three-piece back. If you can
make some suggestions as to how I can repair the arm, I'd be
most appreciative.
-M. Radin, Los Angeles, Cal.
Sandor Nagyszalanczy replies: As far as I can tell from your
description and photos, the problem with your captain's chair's
backrest has to do wim short-grain failure. By making the entire
backrest/arm assembly from only tl1fee segments, as shown in
the sketch below, the ends of each segment run mostly across
the grain. As you discovered, mese areas of short grain are inherently
weak. Even if you hadn't broken the backrest by driving
the spindles into it, the back would've likely been broken by
someone leaning back in the completed chair.
Top view
of captain's chair
backla rm rest
Constructing back from
four short segments yields
less grain runout and results
in a stronger back.
Short grain in these
areas is weak and
susceptible to
breakage.
I think me easiest strategy for repairing me chair is replacing
the entire backrest assembly. Since you used yellow glue, I'm
afraid there's no easy way to remove the backrest from tl1e spindles.
Some woodworkers have successfully used lacquer minner
24 Fine Woodworking