Made primarily from PVC pipe, this design has many good features: It looks cool. It has a connector and valve for a garden hose for instant on-stand water fills, an easy to read pressure gauge, 12' of air line, adjustable rear legs to allow for angled launches (into the wind). It's tough and stable, and lifts the rocket off the ground a good foot allowing for easy rocket set-up (latching the hold-down mechanism, arming the Tomy timer, etc.).
Now for the down side... as it is a manifold design, a lot of pumping goes into filling the maifold as opposed to the rocket... a waste of time and effort.
These shots don't show the hold down mechanism or the air line attachment. The air line was connected to a barbed tee added at the pressure gauge
The rear legs are NOT pressurized, as they are adjustable (they rotate in the tee) A bulkhead seals off the pressure manifold.
A better view of the garden hose coupling and valve. Filling in this manner also aids in pressurizing the rocket, saving strokes in the bicycle pump.
Different length launch tubes can be screwed into the threaded fitting in the launch stand.