Kevin's Fixed Height Tripod Project
Page last updated: 2001 September 12
Fixed Height Tripod
Start of the Project: 2003 March 21
Every year I and many other Astro-Dudes partake of the Star Party known as StarFest,
held at Mount Forest Ontario. And every year we come back full of ideas and energy to do
something about them. This fixed height tripod came from the design of
of the Belleville Astronomy Club,
which he brought to Starfest 2001 and also
to the 1st annual
to replace a rickety old variable height tripod that was a pain to move around
and was always pinching fingers off!
to use as a mount for the Voyager telescope, where standard camera tripods were
often too small and unstable.
Building an add on wedge to mount a barndoor tracker, which also suffers from
too small camera tripods
The design is not changed from Les's basic design (195kb
adobe acrobat file).
Three legs which are friction fitted to the top table surface and three smaller
arms that limit the leg spread, with a tray sitting on top.
x4 1"x2"x8' pine (legs and tray arms) $3.50
x1 12"x16"x1/2" plywood (can use 3/4" as well) (table top and tray base)
x1 12"x12"x1/4" plywood (tray)
x1 2"x2"x12" pine (leg mounts)
x3 2" hinges $3
and x7 #4x1/2" wood screws (tray base to hinge)
and x6 #4x3/4" wood screws (tray arms to hinge)
x3 1/4-20 carriage bolts 3.5" long (leg mounts) $1
x3 1/4-20 carriage bolts 2.5" long (tray arm mounts) $1
x6 1/4" washers
x6 1/4-20 lock nuts $1
x6 1 3/4" (if using 1/2" plywood)
or 2" wood screws (if using 3/4" plywood) (table top to table mounts)
x6 1 1/4" wood screws (legs)
x1 24" of 1/2" quarter round molding $2
tape measure, tsquare, drill, jigsaw, palm sanders
#80, #240 sandpaper, clamp, counter sink drill bit, 1/4" drill bit, small 1/16"
- Table Top
Mark the centre of an 11x11 square and drill a 1/4" hole.
Cut an 11" circle from the 1/2" or 3/4" plywood. We used a large dinner plate to
trace the circle then a jigsaw to cut it out and then #80 sandpaper on the
palm sander to smooth it out, followed by #240 sandpaper.
Cut two 48" long legs from the 1"x2" pine. Clamp the two together and
pilot drill holes at 4" and 8" from one end. Glue from the bottom to the 8" mark
or a little further, put back together and install two screws, 1 1/4".
The free ends should be able to spread
apart 2" without a problem. Mark out a drill hole 3/4" from the open end of the
legs and drill a 1/4" hole through both pieces of wood. Using a jigsaw or saw
round off the open end to allow the legs to move without running into the
bottom of the table top.
Repeat for the other two legs.
Sand down the legs
- Leg Mounts
Cut a 4" long piece from the 2"x2". Drill a 1/4" hole 3/4" from one end and offset
more towards the bottom of the block rather than centered, say 3/4" from the bottom.
You can taper them (which we did for the first prototype but not the second) as well
Repeat for the other two mounts. Sand down the mounts
- Tray Arm
From the leftover 1"x2" cut out a 9" piece. Drill a 1/4" hole in one
end 3/4" from the end and centered. Taper the other end by slicing off
a piece approximately 1" from the top. Repeat for the other two arms.
Sand down the arms.
- Table Top
Draw 3 lines on the bottom (to align the mounts) and top
(to align the screws) of the table top 120 degrees apart.
Glue a mount and align in so the outside edge just comes up to the outside of
the table top. Clamp and turn over. Drill pilots holes 1" and 3" from
the outside edge, drill counter sinks and then install two 1 3/4" screws.
Drill them down past the surface of the table top.
Repeat for the other two mounts. Sand down the table top.
- Leg assembly
Line up a leg with the leg mount and insert a 3.5" carriage bolt. It should
go all of the way through with a little force. secure with a washer and a lock nut.
Tighten all of the way for now.. then loosen off the lock nut a little
later to test the leg swing. The carriage bolt head bites into the wood and
prevents the bolt from turning.
Repeat for the other two legs.
Mark the center of a 12"x12" piece of the 1/4" plywood and drill a small pilot hole.
Next mark out and cut an equilateral triangle (inside angles 120 degrees), 12 inches
a side. Then mark out 2 inches from each point, draw a line across and cut them
off. You should be left with an 8" a side equilateral triangle. We cut off the ends
as they stick out quite a lot when the legs are stowed. You are now going to cut
out an equilateral triangle tray base from the leftover 1/2" or 3/"4 plywood.
This should be a triangle with 6" sides. Attached the hinges to each point
with the hinge itself inside the wood so the tray does not overextend when
deployed. Drill pilot holes and use two small #4 or #6 1/2" screws in each hinge.
Attaching the tray arms is next. With the tray base upside down,
fold the hinge up, place the tray arm with the pointy end onto the inside of the
hinge, align and drill a pilot hole in the farthest hole from the hinge then put
in a #4x3/4" screw. Drill a pilot hole in the next hinge hole (it might have 3)
and put in a #4 x1/2" screw. Repeat for the other two arms.
Now attach the tray to the tray base by gluing and using a single #4x1/2" screw in the
centre from the top
- Tray walls
Optionally you can cut up three 8" sections of 1/2" quarter round molding and
glue it onto the tray, leaving three "openings". This is to help items stop
rolling off the sides.
- Mounting the Tray
Set up the tripod with the legs apart. Insert the tray from the top and bring the tray down
with the arms entended until the tray is level and the arms are level.
Pull out the legs until the arms no longer jut out from the legs.
Mark a leg for a 1/4" hole and measure it (it should be approx 18" +-).
Mark the other two legs. Remove the tray and drill a 1/4" hole in each leg
(through both pieces of wood). Put the tray back in and connect
each arm to each leg using a 2.5" carriage bolt and secure it with a washer and a lock
nut until the carriage bolt is firmly in the wood, then loosen off a bit.
The tripod should now be able to close by putting your hand under the tray base and pushing upwards
and open by pushing down on the tray and pulling out one of the legs.
Lastly, open the tripod to it's fullest extend. Draw a parallel line to the
floor on the feet so that when you cut that bottom bit of leg off, the entire foot
will rest on the ground, and not just the tip of the foot. Repeat for all three legs.
Click here for a gallery of all of the photos, not just the ones display here.
After the Fact
The table top surface.. flat, strong and stable.
It took about 4 hours for the first tripod, mainly figuring out how
things were supposed to go.
The 2nd one went together in under 2 hours. We plan on finishing them, one by
paint and the other by a clear varathane.
One will have a wedge attached using a 1/4-20 bolt and be used on a small
The other will be tested on the Voyager telescope by attaching it's base using a 1/4-20
bolt. It will also be getting a custom built wooden wedge (see next project!)
to allow a barndoor to be mounted on it. My barndoor currently is mounted on my
camera tripod with a quick release mount. Too bad it doesn't lock down
Total Cost: under $20
It helps to have scrap wood hanging around (1/4", 1/2" or 3/4" plywood).
I happened to have 1/4" and 3/4" plywood leftover from another project and used it.
You can shorten the legs by up to 3 inches or so (up to the first screw) if you
are a vertically-challenged person.
The 1st tripod has had two coats of exterior grade white latex paint and now
will get 3-4 coats of water based varathane.
The 2nd tripod got two coats of oil based hard shell spar varnish directly on
the pine and a light sanding.
Onto building the wedge!