Thread: Building a timber platform

Are there any other criteria:
- Does it have to be moveable? Wheels?
- What sort of surface needs to be on the top?
- Does it matter what it looks like underneath?

75x50mm pine, construction ply and lots of screws
You will end up with something like a large packing crate, paint it whatever colour you wish and it should be strong enough to support a small house.
You should be able to design something so it can be dismantled for storage/ transport/ re-use as needed.

Cheers

Ian

Hmmm, even on edge 2x3 pine is not going to be strong enough to span 3 metres. It would need struts up the middle. You could make up 4 or 5 cross braced 2x2m frames and join them together with 3m rails, then clad the lot with 19mm ply. Might be a bit shakey 2 metres up though. It's only 400mm short of needing a handrail under OH&S rules

Why don't you just hire some scaffold? I've got something like that on a job now and it's only $65 per week. It will cost you hundreds to make it from ply. You can even get a mobile tower that you can wheel around. That will cost you more like $200 though.

Adam
To be safe you need to build as walls and a floor. This means
"wall framing for the sides 75x50 studs should be OK with same size bottom and top plate. Nail studs to . Face with approx 12mm ply and nail/screw ply to studs. This will remove the need to cross brace the "walls" to stop the whole shebang from twisting or rocking. Put cross ties between the opposite bottom plates just for a bit of stability to the bottom of the wall.
The top of the box needs to be built as a floor. So put joists across at 600 centres and spanning the 2 metres not the 3 metres, this reduces the span and therefore the size. These need to be 100x50 to be safe. Provide a "floor" out of ply or Patricle board with the joints centred over the centreline of the appropriate joists (ergo the 600 spacing for the joists as the sheets come in 1200 widths) You can use a bit of cunstruction adhesive as well if you really want to impress. You can house the joists over the top plate if you want but I'd guess that it really isn't necessary; skew nailing/screwing is most likely quite OK.
Lastly you will need to trim in a batten along the 3 metre edges of the floor framing. This needs to be housed into the top outside corner of the ends of the joists to pick up and provide fixing for the wall and floor framing
Hope this helps
Cheers
HarcX

For a platform on or by a stage, scapholding is great - easy to adjust to your needs and designed to bear the weight of people moving about. You can dress them up with plywood or sacking etc. The mobile platforms are not so good if you are using them on a sloped stage.

Adam
additional questions:
how will the 4-5 people get onto the platform? by stairs or a ladder?
will the platform have a handrail?
will the platform be fixed in place or do you have to move it arround?
what sort of floor will it be going on? Is this floor level?
can it be fixed to the floor by nails, screws or bolts?
Does the platform have to be timber? Is scafolding an option?
will there be any horizontal load on the platform? things leaning against it, people swinging off it?
rather than your stated dimensions, can the platform be 2.4m wide, 2.4m high, and 3.6m deep? — this would mean that if you use ply, you won't have to cut any sheets.


This is what I'd do
build four corner boxes, each 1.2 x 1.2 x 2.4 high framed using 75 x 50 pine at 600 centres with a top and bottom plate (the top plate on all four sides would be located about 90mm below the top of the box. Sheath on two adjacent sides and the bottom with 19mm construction ply.

build two side boxes, each 1.2 x 1.2 x 2.4 high, framed using 75 x 50 pine at 600 centres with a top and bottom plate (the top plate on all four sides would be located about 90mm below the top of the box. Sheath on one side and the bottom with 19mm construction ply.

I'd screw a 300mm deep ply brace across the top of the each open side of all six boxes. I'd place this brace on the inside of the frame.

I'd bolt these boxes together to form the platform and weigh them down with about 50kg of dry sand (in bags) per box — this is why each box has a bottom. The counter weight isn't needed if you can bolt each box to the floor.

I'd then lay 100 x 50 joists across the top plates at the appropriate spacing and use yellow tongue flooring for the platform's top.

I'd get the ply supplier to 3 sheets in half for box bottoms and strips off another sheet for the bracing.

I've gone for a 1.2 x 1.2 module because, though heavy, two people should easily be able to move them into position.

If you must have a 2 x 2 x 3 structure I'd follow the same basic design but use 500 centres for the studs and definitely get the ply supplier to cut the sheets for me.

ian

comming from an entertainment industy background.
I would strongly recomend for a platform of that height, Either scafolding or portable stage (if you have a supplier that will do that height).
With current safety expectations I would not entertain anything but properly rated equipment in this context.
If it was under 900mm it would be a whole different thing but at 2 metres you are in a whole lot of trouble if it aint right.
If you are in any of the formal theatres you probably will not have any option.
It will be rated gear and there will be other compliance issues you will have to deal with such asproper means of access, guard rails on the back and sides.

If you have access to australian standards check out the stuff on staging. sorry cant give names or numbers.

Sorry to be a pain but there it is.

Can anyone recommend a scaffold hire place in Sydney? The places I have rung are all more like $100 rather than $65. thanks

Originally Posted by silentC

Are there any other criteria:
- Does it have to be moveable? Wheels?
- What sort of surface needs to be on the top?
- Does it matter what it looks like underneath?

Not on wheels or moveable
Plywood type surface would be fine
The platform will be hidden

I was talking to someone about this last night and we reckoned that scaffolding is the way to go. They will come and set it up for you. If it collapses, you are covered by their liability insurance. If it's an amateur production, it probably doesn't matter too much but then people sometimes lose their community spirit when they have been injured. It is 4" short of needing a handrail all the way around. You'd still want one on three sides at least.

What about dropping the height a bit? Say 1800 or so. Might make it cheaper and it would be a little bit safer.

Can't help with a hire firm. If you know any builders, painters or brickies, talk to them. Ask the actors and stage crew if they have a cousin or friend in the game. Some builders own their own scaffolding if they do enough work. Maybe the show could be sponsored by them and give them front row seats...

Just keep in mind that if you do it and it stuffs up, you're the one who is going to have to face the music.

To get insurance cover for this stuff now you have to get the rotten thing inspected & certifed by an engineer.

We have struck this problem at our local theatre at Malanda.

Try this site http://www.stageweld.com.au/stage_seatsystems.htm

If you plan to use the stage for a public event then you should have the stage designed and certified by a qualified structural engineer. The stage should comply with the relevant Australian Standards (ie loading codes etc).

Im sure you could build something strong enough. However, are you willing to put all of your assets on the line if something goes wrong. People love litigation these days.

Thats my two bobs worth.

Adam
Further to my last on this. Proceed with caution
There may be exemptions because you are dealing with a theatre set but I don't know of any. This being the case you need to comply with the BCA (Building Code of Australia). The details I gave you previously are a guide to compliance. Strictly speaking, because the drop is more than 1000 you also need to provide a handrail (rediculous isn't it)
As Tarlox and others suggest, the vulture called litigation is sitting up in the fly space just waiting to feast
It's a bummer but it is reality
HarcX