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Telescope Transport Devices

Stewart Sled
or Tripod Platform Design

by Ed Stewart <>

Being an observer of human behavior, including my own, I realize that enthusiasm for setting up your telescope soon drops in direct proportion to the effort it takes to set it up. Thus, I decided to make the set-up easier for my Meade LX200. I decided that keeping the tripod and scope assembly together along with its power supply and other needed accessories as a mobile unit would eliminate most of the effort in getting ready to observe from my home.

Update 1/1/98, it's been over a year since I started using the "Stewart Sled" as my friends call it, and it really has been effective in keeping up my interest in observing frequently from home. Feels good to see them in use at star parties with the owners explaining their use to others. Let me know if you come up with an improvement to the design--e-mail link on the Home Page. Like the modifications from John Hilliard at the bottom of this page and the alternate designs to the right.



 Construction of the Stewart Sled is below:

Stewart Sled

Links to Alternate Designs

Caster Tripod Sleds 
T-Frame Telescope Transporter 
Scope Transporter 
Scoporter Design
Field Transport System 
Portable Scope Stand 
Scopebuggy (commercial)

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.

Bottom View of SledPutting 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.

Sled-Front View

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.

Astronomy MagazineThe story presented here was the subject of an article in Astronomy , March, 1997, pages 92-3.









Subject: Stewart Sled / Accessory Tray Modifications   Top Button

From: John Hilliard <> 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.