Fence Systems for Accurate Table
Saw Ripping
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Ripping
wood is a primary function of the table saw, and because its
importance, many manufacturers pay particular attention to the
quality the rip fence on the saws they offer. Still, many
factory fence systems lack the reliability and precision that
would qualify them for exacting work. In this article, we’ll
look at the basic requirements for good table saw ripping, and
how an after-market fence system, like the
Accusquare Fence System or the
Vega Fence System, can improve the ripping performance of a
saw that’s suffering from “fence problems”.
Is Your Rip Fence Up to Par?
What makes a good rip fence? One of the most important
factors is whether the fence offers reliable parallel alignment
with the blade. When you lock a rip fence in position, it should
be automatically drawn into near-perfect parallel alignment with
the saw’s blade, and this should happen unfailingly – you
shouldn’t have to make frequent adjustments to the fence, or
meddle with it to get it aligned. This is a very important point
- accurate ripping, a clean cut, and even your safety depend on
this alignment.
Checking for Parallel Alignment
Checking the parallel alignment of you table saw’s rip fence
is the first step in evaluating your saw’s rip fence. But to
check the alignment of the rip fence, you first need some
information about the alignment of the blade in relation to the
table saw’s miter slot. For accurate ripping and crosscutting on
a table saw, the blade must be in parallel alignment with both
the miter slot and the fence. Since the miter slot cannot be
“adjusted”, the first step in the alignment process is to bring
the table saw blade into alignment with the miter slot.
Aligning the Table Saw Blade
The procedure for aligning the table saw blade with the miter
slot varies from saw to saw. The owner’s manual for your saw is
the best source of information for making this adjustment. A
good
table saw book, like Ian Kirby’s “The
Accurate Table Saw” can also help by providing detailed
information on the “hows” and “whys” of table saw adjustment and
maintenance. But in brief, the procedure for aligning the blade
with the miter slot goes as follows:
Mount a blade in the saw and raise it to its highest
position. Lay a straight edge on the surface of the table so
that it is centered across the diameter of the blade and tight
up against the blade plate (make sure that the straightedge is
in contact with the blade plate itself, and not resting on the
blade’s carbide teeth). Next, measure the distance from the
straightedge to the miter slot milled in the surface of the
table at each end of the straightedge. If the measurements do
not agree, the blade is out of alignment.
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For the most accurate table saw adjustments,
consider a precision alignment tool.The
A-Line It Table Saw Gauge reconfigures in seconds to
test table saw alignment, arbor shaft runout, blade and
flange runout, and rip fence alignment and straightness |
Follow the manufacturer’s instructions for adjusting the blade
alignment. In most cases this will involve loosing three of the
four bolts that attach the trunnions to the saw, tapping the
assembly into the correct position and retightening the bolts
(be sure to check the alignment again when you are finished to
make sure that the act of tightening the bolts didn’t pull the
blade out of alignment).
Checking for Parallel Fence Alignment
Now you are ready to check the alignment of the fence. Since
the blade is now in parallel alignment with the miter slot, you
could simply check the alignment of the fence against the miter
slot, but a more accurate reading is supplied by setting the
fence in a few positions at varying distances from the blade and
using the straightedge again to check the alignment of the
surface of the fence and the surface of the blade. The
measurements of the distance from the surface of the fence at
the front end of the fence and the back end of the fence to the
straightedge should agree. If they don’t, the fence is out of
alignment and should be adjusted.
Most fences have a provision for adjusting parallel alignment
– again, the manufacturer is the best source of information on
the procedure. If the fence cannot be accurately adjusted, or if
the degree of disagreement between alignment measurements varies
as the fence is positioned and repositioned, there is a strong
possibility that your current fence is incapable of providing
reliable parallel alignment. If you are generally satisfied with
your saw's other qualities, correcting the problems with the
fence is worth considering.
Other Rip Fence Considerations
Along with providing reliable parallel alignment, a good
fence is also easy to accurately position at the desired
distance form the blade. The positioning scale on the front
fence rail should be easy to read, and the fence should have a
cursor that can be accurately calibrated to produce precise
settings. A useful fence also needs to have a wide enough
capacity to do the work you need it to do. If the fence on your
saw falls short of either of these additional criteria, and a
new saw that comes with a better fence isn't in the plan, an
after-market fence system is the best solution.
After-Market Precision Rip Fences
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The
Rockler Magnet Micro Adjuster is a great match for a
good fence that only lacks a mechanism for fast accurate
micro adjustments. This handy tool lets you quickly and
easily make fence position adjustments in increments of
.001" or less. |
Precision after-market fence systems were developed as a
solution to a deficient fence on an otherwise reliable table
saw, and they can work wonders for ripping performance. Mule
Cabinetmaker's
Accusquare Fence System is one of the most popular
solutions. Accusquare fences can be retro-fitted to most table
saws in an hour or two, and provide easy, accurate positioning
and a 50" rip capacity (along with the option of increased rip
width on the left side of the blade). It's superior quality
clamping mechanism and precision CNC ground parts provide
smooth, effortless positioning, minimum fence angle deflection,
and reliably accurate parallel alignment of the fence in
relation to the blade. The fully adjustable hairline cursor
makes the fence easy to set at accurate distances from the
blade.
The
Vega Fence System is another reliable choice. The Vega
Utility Fence can be fitted to most portable and contractor
table saws, and will greatly enhance the ripping performance of
either. The Vega fence comes in 50" and 28" ripping capacities -
the 28" length is a great way to increase the accuracy of a job
site saw without sacrificing portability. The Vega fence also
comes with a useful micro adjustment mechanism, which means that
you can dial in ultra-fine adjustments (in the thousandths of an
inch range) for precision rips or for setting up dadoes and
rabbets.
The Vega system equals the Accusquare system in quality of
materials and manufacture. The Vega system’s front fence rail is
made from precision rolled plating quality tube, which is
chromed and polished smooth and has extra thick walls for
superior rigidity. The Vega fence head is extruded from high
strength aluminum and is machined to closely match the contour
of the miter bar. The rigid and precisely straight front fence
rail and the precision matched fence head make for not only
solid reliable positioning and alignment, but also an especially
smooth movement of the fence from position to position.
Both
of these precision fence systems are designed with easy
installation on a wide variety of saws in mind. Either system
would constitute a vast improvement over the fence offered on
many less expensive home shop saws and both rival the best
systems available for professional-class table saws. For a table
saw that’s generally sturdy and reliable, but suffers in the
quality of its fence system, either the
Vega Fence System or the
Accusquare Fence system presents a logical and affordable
route to safe, accurate and reliable ripping.
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