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Simple Solution:
The solution is only two 2"X4" boards, a small piece of 1/2"
plywood, a dolly with soft pneumatic wheels, some screws, glue and few
hours of time in the garage. Looking at the overhead view diagram and
Photo A, visualize the two boards as an upside-down T with the cross member
of the T picked up by the dolly during transport. The tips of the tripod
legs ride in angled holes at the ends of the T-shaped sled. The legs are
held captive in the holes by the outward pressure from the spreader between
the tripod legs. The plywood that is glued over the intersection of the
T to provide additional strength can also carry a battery box (see "Astronomy,"
January, 1996, p. 86-7), accessory box or whatever you need for your observing.
With the scope mounted on the sled, the scope is first safety strapped
to the dolly, and then tipped over to begin wheeling it from its storage
location out to the observing site. With some creative thought you can
have almost everything needed loaded on the sled for a one trip set up.
I find it so convenient that even a quick 30 minute session is enjoyable.
 Putting it
Together
Decide on the maximum spread of the tripod legs based on the narrowest
doorway they must pass through, less 2" to allow for clearance. Cut
a 2"x4" to this dimension for the horizontal member of the T.
Cut another 2"x4" to form the vertical member of the T for the
third tripod leg with a simple butt joint. See Bottom View in photo to
the right. If you are a knowledgeable woodworker wanting to do a stronger
half-overlap joint, allow for this additional distance.
Before joining, it's a good idea to clip off the 90° corners at the
ends of the 2"x4"s to reduce the harsh angle. I ran a 1/4"
round-over router bit over all edges for a more finished look. To make
a butt joint, line up the 2"x4"s in the T shape and drill some
pilot holes for two 1/2"x6" lag screws to secure the horizontal
member to the vertical member.
Next decide on the dimensions and shape for the plywood shelf, allowing
for the items you want to attach to it, and cut it out of 1/2" to
3/4" plywood. Sand off the sharp edges before gluing and screwing
it onto the top of the 2"x4" T.
Now it's time to drill a hole at the angle and size of the tip of the
tripod legs into the three ends of the T-shape using a spade bit or drill
a number of smaller holes in a circle and chisel out the center. Note:
where you begin drilling on the surface must be biased toward the center
of the T by 1/4" to 1/2" to allow for the tripod leg to become
fully spread outward when it's at the bottom of the hole-see side view
enlargement. If the holes are drilled properly, the Meade tripod spreader
knob will apply outward force to lock the leg tips in their holes. If
you have to reduce the original leg spread to clear a narrow doorway,
you will probably need to replace the original 0.5" threaded spreader
shaft with one several inches longer. Note: to adjust the locking force,
extending the legs a small amount will increase their outward spread to
get the grip in the holes you want.
Add some type of foot, such as a hard rubber furniture knob with a central
nail, directly under the three holes to transfer the weight of the scope
directly to the ground and to provide clearance for the dolly's lip to
get under the sled for lifting. Finally, you should varnish or paint the
sled to protect it from moisture damage and to make it look more like
a part of the scope design.
Other Ideas
If you have a tripod like the Polaris series that doesn't have a spreader
type action to the legs, you could run a heavy gauge wire from the tripod
head to the center of the sled with a turnbuckle (like those on a screen
door) in the middle of the wire to apply downward locking force on the
legs. If you want to forego the shelf, just cut two 2"x4" several
inches longer than the distance between two of the tripod's legs and nail
the 2"x4"s to each other in a right angle. Now bolt this 2"x4"
bracket to the dolly's lip. Simply set any two of the tripod legs into
the bracket and tip the dolly over to wheel the scope out.
As with many ideas in telescope making, they just provide the spark for
others to try something a little different--be creative and enjoy.
 The
story presented here was the subject of an article in Astronomy ,
March, 1997, pages 92-3.
Subject: Stewart Sled / Accessory Tray Modifications 
From: John Hilliard <messier27 earthlink.net> Date: Dec., 2000
Our door size and two very sharp turns required that the "Stewart
Sled" be constructed as an equilateral triangle 24" to the side.
To compensate for the small size of the triangle and the height/weight/balance
problem, I put a pair of screw eyes on each corner of the triangle and
loop shortened bungee cords over the connections for the lower spreader
to keep the tripod legs from coming out of their nesting holes when tilting
back or in transit.
With the small size of the sled, the legs cannot be fully spread and
the locking of the scope to the tripod via the threaded rod/spreader bar
does not work. To compensate for this, I put a pair of hex nuts separated
by a lock washer on the threaded rod at the appropriate location so when
putting the scope on the sled, we loosen the rod sufficiently to rotate
the upper spreader bar, then retighten the threaded rod to the stop created
by the hex nut/lock washer combination. This holds the scope on during
the placing of the tripod on the sled and transit.
For feet, I used heavy wooden cabinet drawer pulls (2" diameter
and 1-1/2" high) and attached them with a wood screw thru the nesting
holes for the tripod feet. I put on several coats of polyurethane to seal
the wood.
As to an accessory tray, we made one from 1/2" plywood, 24"
x 12". I cut the center hole 6" diameter +/- which fits over
the tripod head and rests on the hinges for the tripod legs. A bit of
felt liner snugs it against the tripod head and some small stick on rubber
bumpers snug it against the telescope base so it does not wiggle or spin.
It holds 6 - 1-1/4" EPs and 4 - 2" EPs, has a wedge for the
keypad, and a bit of space left to lay my reading glasses/flashlight on.
We edged it with 3/4" edge molding for a bit of a lip and to finish
the plywood edges. We had initially tried a ScopeSaver we have on another
scope but the bolt is too short (no nut to remove). Also, the wood is
"warmer" on the keypad and fingers.
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