I'd likely use the stairs for the "So Long, Goodbye" scene. If I can figure a way to incorporate them into another scene, that'd be cool. However, my fear stems from the possibility of the entire
unit swaying as actors get higher on the steps. I'd likely create a wide staircase, so the suggestion of three stringers is great. Thank you. Should I be concerned with instability? Would I need legs that outreach from the sides for additional support, similar to a
cherry picker? (And while we're at it, what exactly are those legs called?)
Stability of the
unit is going to be determined by a couple of factors:
Width of staircase.
Width of
wagon.
Height of staircase.
Materials used in construction.
Bracing.
If you are making a 4
foot wide staircase then your
wagon should really be a minimum of 6 feet wide.
Construction technicque of the staircase has a lot to do with things as well. If you
build it as a "real" staircase with the stringers knotched to accept the treads and risersit will be stabile but may not hold the capacity of all the Von Tropps at the same time. Using a 1/2" thisck material for the risers will greatly improve the stability of the
unit and reduce the need for as much cross bracing underneath, as the
riser essentially add lateral shear strength to the
unit. You may want to construct the stringers ot of 3/4" ply. a lot of times I will cut out a
stringer traditionally, then
laminate that to an uncut peice of plywood the same width as the peice I started with for the
stringer. This only gives you 3/4" to screw into on each side of the treads and risers, but it adds a lot of strength the to outside of the stringers. Unless my stairs are narrower than 24" I
always add a center
stringer.
Railing isn't even a question, any stair over 3' needs to have a railing, unless it is an
element specifically designed in a manner which prohibits.
The big factor in swaying
etc, and the weakest link in the stability game is going to be your casters, their placement, and you locking scheme.
The casters need to be placed as far away from the
center line on the
unit as possible < but you need them in the center of the
unit as well. >
This will allow the
unit itself to act as it's own
Outriggers which is the word for the arms that come out the side of a
cherry picker, Genie, Back Hoe, Canoe,
etc,
etc.
When you lock down the
wagon on it's spikes it ned to really lock down if it's sitting freen on swivel casters it'll just slide around like Snoopy on Ice.
If you can
build a Pnuematic or Hydraulic
system to lift the
unit onto is casters, then move the
unit into place then
drop the pressure so the
unit is sitting on it's own framing, that would be best. If Not, then perhaps some good old fashion Improved
stage screws and
stage screw cleats could be your freind.
Sorry I got long winded and had to walk away, now I back,
If all this makes sense to you, hurry to your local Psychologist, If not feel free to fire back with more questions.