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Table Saw Sliding Miter Sled
The following is a short discussion
and description of a table saw sliding miter sled in its various configurations.
Cross-cutting on the table saw very often demands high precision. The miter
gauge provided with most table
saws can be very limited in its versatility. There is little bearing surface
provided for the piece being crosscut,
and there is friction created by moving the piece and miter gauge across the
table saw top. This friction can
often reduce precision with much of your effort concentrated in keeping the
piece from sliding left or right and
from rocking. A sliding miter sled addresses these issues by providing a
secondary surface to which you can
rest the piece being crosscut. Once you have locked the piece against the fence
of the sliding miter sled,
it is left only to move the sliding table past the blade to perform a very
accurate crosscut. Below is an overhead
view of the sliding miter sled with attached adjustable fence and to the right
of the blade a fixed auxiliary table.
The auxiliary table serves to keep any offcuts from falling onto the table top
and possibly binding the saw blade
causing kickback. The sliding miter table and the auxiliary table both have
hardwood runners attached
which
are sized to the length of the table saw miter left and right miter slots,
therefore serving to align
both sides of
the miter sled parallel with the saw blade.
Having both the sliding table and auxiliary table in close proximity
to the blade also serves as a zero clearance setup for your cuts.

Below is a view of the far end of the
sliding miter sled fence. The fence itself is a 2 inch high by 1.5 inch thick
laminated slab of hard maple. Any stable hardwood will make a good fence. The
dark hardwood cocobolo
block serves as an adjustable stop block along the 24 inch length of the fence. The
stop block slides along
an
aluminum T-track which has been epoxied into a groove in the hardwood fence. A
vertical fence locking
knob is also visible. This locking knob is attached to a 2.5 inch long cap screw
which screws into a blind nut
embedded into the miter sled base. To the right is the adjustment knob and
mechanism to tune and maintain
the fence
perpendicular at 90 degrees to the saw blade.

Below is another view of the sliding
table fence horizontal adjustment mechanism. The mechanism consists of the
4 in. wide cherry
block, a 2.5 inch long, 5/16 inch carriage bolt with nylon washer and a 2.5 in.
diameter knob.
The
carriage bolt is threaded into a 5/16 inch sized blind nut pressed into the
cherry block and locks with the
large,
plastic star knob. The fence pivots very close to the blade end of the sliding miter sled,
whereas the
adjustments
are performed at the opposite end pictured below. The advantage to this setup is adjusting the fence angle as
far
from the fence pivot point dramatically
increases the accuracy of the adjustment.

Below is an overhead view of a block of
wood set up to be crosscut to a certain length. The block of wood is held
against both the fence and the stop block. The sliding table is then pushed
past the saw blade performing the
cut while the piece of cherry is held against
the fence. A small offcut will
remain on the auxiliary table after the
cut is complete. The sliding table is
then pulled back and the
cherry block removed. The pivot point for the fence
consists of a 3/8 inch carriage
bolt through a precisely bored
3/8 inch hole in both the hardwood fence and the
sliding table base. There is a
7/8 inch counter-bore in the underside of the table for the carriage bolt head.
The carriage bolt is locked
in place with a nylon lock nut and
washer. It is always advisable to stand to the left
of the blade for this operation to reduce any possibility of being injured from
possible kickback.

A second view of the block of cherry
being crosscut to a precise length. Here the cherry board is just
entering
the saw blade. The blade guard above the saw blade has been raised for clarity,
it is normally 2 inches above
the fence of the sliding miter sled.
The auxiliary table to the right of the saw blade is held firmly in place with
4 (1/2 inch diameter) rare earth magnets and cups
embedded into bored holes on the underside of the auxiliary
table. The auxiliary
table can easily be popped on and off the saw table top and the magnets are
sufficiently
powerful to keep it from sliding forwards or backwards. A hardwood runner on the underside of the auxiliary table
for the table saw miter slot, serves to keep the table aligned and to keep
it
parallel with the saw table.

Below the crosscut is complete and
the sliding miter sled is at the far end of its travel. The offcut created by
the
cut is left in place on the auxiliary table. The auxiliary table also keeps the
offcut piece from falling onto the
saw table top possibly preventing a kickback. It should also be noted that the
combination of sliding table and the
auxiliary table automatically create a zero clearance kerf for the saw blade.
This zero clearance kerf greatly
increases the safety of the crosscut as it removes any risk of a small piece
being trapped to the right of the blade.

Below the sliding miter sled has been pulled back
and the cherry block will be removed once the saw has
been powered down. Once the saw has been powered down, the offcut can be safely
removed. The sliding
miter sled increases the safety ,ease and speed of making similar, exact wood
parts. Each piece of wood
will be crosscut to the similar, precise length as the previous piece.

Below an overhead view of a piece of
cherry having a miter crosscut performed at 45 degrees. This sliding miter
sled has been set
up with fence locks at both 90 and 45 degrees, the most often used angles. For
other angles
such as 30 degrees,
it is a matter of swinging the fence to 30 degrees from perpendicular or 90
degrees.
A 5/16 in. hole is then drilled through the base
to fit a blind T-nut for the locking knob and cap screw. The locking
knob hole
in the fence itself can easily be used as a a drill guide. An adjustable
protractor can be used to
determine any angle other than 90 degrees.

Below, another view of the small
cherry block being crosscut at 45 degrees. Notice the small relief angle cut into
the pivot end
of the fence, this provides clearance for the fence end when cutting 45 degree
miters. The aluminum
T-track has also been offset 1/2 inch in its groove to provide for this clearance in the fence. The
sliding table is
guided past the saw blade and pulled back after the cut. The auxiliary table remains in place to
provide a
equally tall base for the offcut which is generated. Any small offcut
pieces are unlikely to bind with the saw blade
as the tight kerf created by both the miter sled and auxiliary table against the
saw blade prevent this.

Below is a close view of the
adjustment mechanism for the fence at 90 degrees. A 2.5 inch (5/16 inch diameter)
carriage bolt is threaded into a blind T-nut pressed into the hardwood cherry block.
The hardwood block is
located at
the furthest point from the pivot point of the fence. The pencil lines are a
guide to setting the fence
exactly at
90 degrees to the saw blade. The carriage bolt head sits against a small
screw set into the fence.
Any adjustments performed at this end of the fence serve to micro-adjust the
fence along its length,
since we perform this 19 inches from the pivot point. . The hardwood block is attached to the
sliding table
base with two screws
counter sunk into the underside of the base.

Below is the front view of the fence
angle adjustment mechanism with the 2.5 inch diameter star locking knob.
This adjustment block is located as far to the left of the fence pivot point as
possible (19 inches) to benefit from
the micro-adjust feature of this distance along the fence. Also visible is the
screw and recessed washer located
along the fence as part of the microadjust mechanism.

Below is a view of the underside of the sliding
miter fence. The sliding miter table has been assembled with
a baltic birch piece approximately 3/4 inch in thickness and 21 inches wide by
20 inches deep. The width and
length are customized to the saw top left area including wing. The miter sled is
2 inches wider than the saw top
to the left of the saw blade. The length is long enough to be able to safely
complete any 24 inch deep crosscuts.
The hardwood runner is also visible. Any hardwood can be used for this runner.
It is important to have the
hardwood runner tight in the saw miter slot with next to no sideways movement.
The runner is inserted into a
3/4 inch dado groove in the underside of the sliding table to a depth of 3/16
inch. The blind T-nuts for both the
90 and 45 degree settings are also visible along with the head of the pivot
carriage bolt. Every hole drilled in
the underside is either counter bored or countersunk to prevent the screw or
bolt head from dragging on the
saw table top. The sliding miter table is initially approximately 1/4 to 1/2
inch wider to the right of the saw blade.
Once the sliding table is inserted onto the saw table top, this 1/4 to 1/2 inch
piece is trimmed with the saw blade
and the result is a perfectly aligned, zero clearance sliding miter sled table
edge parallel to the saw blade.

Below is the underside of the auxiliary table. There
are four rare earth magnets embedded into the left and
right of the hardwood runner. These magnets serve to keep the auxiliary table
locked on to the saw table top
fixed in place and to prevent it from sliding forwards or backwards along the
table top. The runners are sized at
3/4 inch wide by 3/8 inch deep for the miter slots in this particular saw table
top. The auxiliary table is also
initially oversized by 1/4 to 1/2 inch along the saw blade side. This piece is
then trimmed by the saw blade to
create a zero clearance gap between the edge of the auxiliary table and the saw
blade. The dimensions for this
auxiliary table are 18 inches wide and 24 inches long.

Below a view of most of the hardware necessary for a
sliding miter sled such as described. Any or all
of these individual components can be replaced with equivalent parts. Other
variations of this sliding miter
sled exist with different features. The sliding miter table can have as many or
as few features as necessary.
Some other features might include a longer fence, a sliding extension to the
fence for much longer boards.

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Copyright © 1998-2006 White Mountain Design
Last modified:
March 09, 2006
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