ImagineerTom

My instinct would be to ask “does he use a mobile phone?” If he does and it’s surviving repeated daily exposure then a radio mic shouldn’t have any problems from a one-off event. If hes told not to use one (or he’s getting through a lot of them) then you’ve got your answer.

I’m acutely aware that blue room posts appear in google searches so whilst I’m not specifically expecting the OP to have this level of emergency planning it it’s important that the claim that “fire alarms aren’t needed outdoors” is corrected otherwise someone else will be hosting a bigger event and decide they don’t need safety infrastructure because someone on a knowledgable forum said it was fine and no one corrected it.

Again just to be really picky - the school teacher may have decided that is not the case but the law isn’t so loose. Lots of safety regulations require a “fire alarm” (a way of notifying the crowd of an incident and the need to evacuate immediately) to be used in open air situations. Outdoor music festivals have a whole infrastructure of fire exits, secondary and backup lighting systems, backup PA systems, trained staff with megaphones and portable lights, fire extinguishers and literal fire engines on site ready to react even though the entire event is “in a field” We’ve also had to install “fire alarm” (heat or smoke detection systems) in tents, trailers, under grandstands, under stages - again the law (and the risk assessment your insurer will expect you to have to be covered) requires appropriate monitoring systems or processes in place to ensure a small fault can’t grow into a big fire unseen and suddenly become a really big problem. The idea that because it’s outside or not a public event means that it doesn’t need proper safety systems or to follow current safety legislations (and best practice) is a nonsense. Whether the audience is the public, visitors, employees or somewhere in between the obligation to be safe always remains however inconvenient that might be to the administrators

Just to make this very very clear, the LAW requires you to have a separate emergency lighting system for the “venue” there is no shortcut or work around for that. There is a prescribed lux level of light that is required at specific points along any evacuation route not just within a venue but all the way to evacuation muster points. You /may/ hit that level with light spill from stage lights but if you don’t then you’re not compliant and your event is dangerous. and just to emphasise how much you don’t seem to truely understand the situation- earlier you talked about your system being similar to a building’s centralised battery backup system; emergency lighting on new builds (and any existing theatre that has had any kind of refurbishment at all) has been based on stand alone, self contained, self powered emergency lighting units for close to 20 years. Regardless of the artistic requirements of the show the rules about emergency lighting, evacuation routes, staff training & rigging safety do all apply to this show no matter how much you try to explain their need away.

Just to re-emphasise this. Regardless of whatever artistic lighting choices the show desires the “venue” is required by many many laws to have emergency lighting & safety systems in place which (unless you’re splashing some serious cash on self contained and wireless options) will require generators and infrastructure you’re currently trying to avoid. Also the “chandelier” will need some substantial rigging and infrastructure just to keep it up and safe in common uk summer weather scenarios. are you sure this event is being planned and spec’d properly because for the information provided it looks like it isn’t?

The only real “robust” machines are the old jem designs, now rebranded as Martin. I’ve seen those units dropping with water and dropped of the back of a lorry still working. Any of the modern drop ship brands (antari, chervut, etc) are designed to hit a price point not actual long term stability.

That is terrible advice - this WILL impact the properties of the beam and almost certainly reduce its rating. Steel frame construction increasingly “economises” its design to ensure parts are only just strong enough to meet the forces (and safety factors) applied to them- compromising the integrity of the beam by randomly welding non-standard connection parts to it is crazy and needless. Non-destructive connectors are perfect for the task the OP is trying to achieve, permanent structural modifications absolutely are not.

If this is a touring show then remember each venues tech manager my well want to see some fire safety paperwork for your “screen” which an old sheet or a show curtain won’t have. isn’t a better solution to use a good quality screen and render some “decay” and dirt into the video itself?

Tbh unless you’re happy to pay 4 figures all anyone will do it buy a radio controlled car and glue it into your frame as it’s a technology that will “just work” so you might as well just do that yourself. if it’s got to be especially powerful or if you’re adding multiple extra motions then a custom solution might be the only way but virtually every Panto and single year touring musical that has a prop like this is actually an off the shelf RC car and a lot of hot melt glue.

Why? Multi track recording has been accessible and easy for decades; find out what precisely he is trying to achieve as it can't surely be just to record "stereo"

Normal, non surfaced ply all the way. You can’t really paint it, if it gets damaged it’s unrepairable and every screw or staple that goes into it adds another point of failure. Regular ply painted black is cheaper, easily repairable, durable, adaptable / flexible in actual use and will match any other decking you sub in. as for painting - with a roller (on a stick) it’s reasonably quick; because of the quantities you’re going to do invest in a £30 spray gun from Toolstation and spray paint them: 4-5 thin layers (each one at 45degrees to the last) will give you a fast, even coat in surprisingly little time.

pushing back a bit here - the OP does ask for something that does it "automatically" suggesting there isn't currently backstage staff with the time / skills to do this manually, the OP also works in contemporary dance which is almost universally under-funded and under staffed from a tech crew point of view; these are the markers that normally indicate to me that this automation is to save money / reduce staffing when in reality its not going to. The op is also very clear about this starting at almost ground level and raising up to 3m which puts all the pantographs / chains / home made systems mentioned right into prime "something gets caught" height range so if implemented would require multiple safety interlocks and stage crew to monitor when in motion; more complications and costs. Also dancers in dance companies do have an incredible ability to put themselves in harms way backstage. to the OP - the closest to off-the-shelf you will find is going to be something from wahlberg but please do also consider your design and implementation very carefully - something which can lift 30kg of moving light 3m up and down will punch holes in sets, tear curtains and slice bits off humans within seconds if anything goes wrong so you do have to ensure you are taking proper precautions and have considered every worst case scenario.

Just to be the grinch here... what you're making is ultimately a piece of automation so in-show-use it will need lots of safety switches / crash sensors on it, some heavy-duty safety assessment paperwork and probably a dedicated member of backstage team responsible for checking it and operating (or overseeing its "automatic" operation) in the show. This is something that will require $00000's of equipment (that admittedly you may be able to rent rather than buy) and a weekly operating/staffing cost of at least $1000 so before you get your heart too set on this its worth stopping to make sure the show has a budget that can absorb those sorts of costs?

Just a general note based on experiences helping others - just because you /could/ 3D print a perfect model, doesn't mean you can. One example that jumps to mind was someone who wanted to print a model of a grand piano for a model box. He found a stl file, scaled it and couldn't get it to print, he used CAD to make his own model, scaled it and couldn't get it to print - in both cases I had to point out that the spindly legs of the piano were so thin that when scaled to modelbox size they were barely 1mm thick; virtually impossible to print. In the case of the steeldeck pieces linked above they would appear to have been designed with 3D printing in mind but if you add legs to them make sure you 3D print an actual solid leg, not a scaled scaffold tube as the latter would again have walls so thin the model would either fail to print or crumble at the slightest touch. Sometimes with modelboxes getting a shape that fills the correct volumetric space is more important than producing a photo-real, perfectly accurate 3D part.

The mister / fan / LED’s system I describe will give you exactly what you need - the “flames” will be effectively invisible until you turn the LED’s on and or you can ramp the fan power up (turn on a second fan for a few seconds) will make the visible flames suddenly get visibly much taller for a few seconds.