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Author Topic: Black truss  (Read 9450 times)

Timoteus Ruotsalainen

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Black truss
« on: April 17, 2004, 04:31:50 am »

I'm more of an audio guy so this may be dumb question BUT is there such a thing as a black truss. I was thinking why would people want to use aluminum colored par cans.  IMHO they don't look good. I came to the conclusion that the silver pars look better with silver truss than black ones on silver. Now if a black par on a black truss could be used that would look better, at least IMHO.

Why don't shows use black truss?

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Timoteus Ruotsalainen
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Brian Ship

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Re: Black truss
« Reply #1 on: April 17, 2004, 04:44:08 am »

They do, you just can't see it Very Happy

You should be able to purchase black or silver truss, otherwise painting and powder coating the truss is very common.  You just need to be careful with C-Clamps on it or you have black/silver poka-dot truss. Shocked

Kidding asside, powder coated truss will hold up better, think I'm running Silver, Black, Red, Blue and Green truss at the moment.  There is some structural intregrety issues with powdercoating possible so verify with the manufacturer it's possible and coordinate the specifications for doing this with the powder coater if that's your choice.  Not in the know about such details but it could have something to do with temperature and other factors.  Think this was a Stagecraft type posting on that other website a while back.

"Truss Condoms" - PVC 3/4 cuts of tubing are frequently used with C-Clamps, or half cheseboroughs and other truss clamps are better used with any painted truss.  Hope it helps, others certainly will know more about it -  I don't do many shows anymore or order the stuff so my need to know is not much beyond this.
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Timoteus Ruotsalainen

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Re: Black truss
« Reply #2 on: April 17, 2004, 04:58:12 am »

hhhmm maybe I'd have to contact Miffe but I have looked and haven't seen any almost any shows here in Finland that use black truss.  Of course the arena shows are in another league.

a black truss, straight from the manufacturer, truss condoms and black pars Wink sounds great. Add black flown speakers and subs under the stage. Black mic stands, cables, and cases.Heck get a black midas. If I ever get that stuff maybe i should call it "The Black Hole" Wink

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Timoteus "No, a purple midas won't do" Ruotsalainen
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len woelfel

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Re: Black truss
« Reply #3 on: April 17, 2004, 08:44:55 am »

The Stones had black truss on their last tour.  I've seen a lot of it.  Maybe you've not seen it because the people you work with have the silver colored stuff and not enough people requested black to make it worth the investment.  

Rob Kettridge

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Re: Black truss
« Reply #4 on: April 17, 2004, 05:29:12 pm »

Black truss is very common over here, well in the tours that i have anything to do with. Trouble is that it's very easy to scratch as people have said. I often think that a scratched and pitted black truss looks worse than a silver one. Only thing i've ever seen that doesn't scratch in this way is the fly bars at a theatre i work at. No-one know's what they're painted / coated with but it doesn't wear off at all no mater what you do to it.

Confused

Rob Kettridge
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Rob Kettridge

Craig Leerman

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Re: Black truss
« Reply #5 on: April 18, 2004, 12:11:36 am »

There not only is BLACK colored truss, but many other colors as well!

Alumimun truss is more comon because of two main issues, Maintenance and Look.  As others have already said, if you scratch standard aluminum truss, it still looks good. In fact, from 10-20 feet away, even really banged up/scraped/nasty aluminum truss looks great to the human eye!  

Black or other colored truss, no matter how the finish is apllied will not look as good after it is scraped and dinged.  On the road, it is very hard to keep small dings and nicks off the truss. Trusses get slid into the truss or stacked ontop of each other or on road cases. Nicks and dings and scratches are a given on a road show.

The other main reason you see aluminum truss more is the Look of it. While you may prefer the look of black truss, many designers and clients prefer the "industrial" look of aluminum truss and aluminum cans.

On concerts, you will probably see either aluminum or black truss and cans, with aluminum being more popular. In theatre type gigs, you are more apt to see black truss and cans (and lekos, fresnels, etc).

At trade shows, you will see a lot of truss in many different colors. Trade show exibiters like to color coordinate their booth displays to their company logo colors, and the truss is no different. Recently at a trade show in Vegas, I remember seeing truss in RED, GREEN, BLUE, YELLOW, and POLISHED ALUMINUM in different booths. display truss is usually smaller sized and lighter weight than concert type truss, so its easier to handle carefully so as not to scratch or damage the color.  Many display truss structures actually pack up into trunks or shipping crates or on pallets for delivery, so the pieces dont get damaged.  Also, display trusses may be used only a few times per year, so the colored truss will stay looking good longer than concert type truss whick may get loaded/unloaded in trucks on a daily basis.

Craig
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I'm so old, when I was doing FOH for Tommy Dorsey, to balance out the horn section I would slide their chairs downstage and upstage to mix!


dawen

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Re: Black truss
« Reply #6 on: April 19, 2004, 07:20:26 am »

Timoteus Ruotsalainen wrote on Sat, 17 April 2004 10:58

Black mic stands, cables, and cases.

And what color of cables do you use now, pink?  Shocked  Razz
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Timoteus Ruotsalainen

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Re: Black truss
« Reply #7 on: April 19, 2004, 08:48:05 am »

I was thinking more like orange... To match with my power cables. ;)

Seriously I have seen shows use all kinds of colors. Local boys must have bought some kind of a rainbow set cause they have red, blue, green, orange... Sure it might be easier to color code some cable but I don't like the fact that your stage looks like a rainbow, heck that's what lampies are for. And THEY don't need my help for that ;)

Craig you must have missed the tongue in cheek after the stuff about orange cables.

I DON'T use the non rated cables.

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Timoteus Ruotsalainen
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Craig Leerman

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Re: Black truss
« Reply #8 on: April 19, 2004, 10:48:33 pm »

Quote:

I was thinking more like orange... To match with my power cables.


I hope you are not using standard ORANGE EXTENTION CORDS for theatre use.  Standard extention cord (like the orange ones sold at hardware stores and home centers) are allowed for home use, and in construction use, but are not rated for use in theatres. The jacket insulation on those cables is not thick enough to stand up to theatre use.  Not to mention that the orange color stands out like a sore thumb instead of blending into the background like a black colored cabled will on stage.

Play it safe and get rid of all your orange extention cords for lighting and buy or build 12 gauge cords made from SJO or SJOW cable.

Craig

Craig
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I'm so old, when I was doing FOH for Tommy Dorsey, to balance out the horn section I would slide their chairs downstage and upstage to mix!


Craig Leerman

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Correction!
« Reply #9 on: April 20, 2004, 10:13:10 am »

Ship  (Brian) pointed out to me that I added an extra "J" to the cable designation.  Its not "SJ" series cables that are allowed, its the "S" series (like Soow).  

I guess its time to put down the Playboy mag and refresh my memory with a copy of the NEC!   Rolling Eyes  

Craig
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I'm so old, when I was doing FOH for Tommy Dorsey, to balance out the horn section I would slide their chairs downstage and upstage to mix!


Brian Ship

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Re: Correction!
« Reply #10 on: April 21, 2004, 10:57:02 pm »

 Shocked I was hoping to keep it as an off line correction because in general Craig's point was valid.  Keep the Zip cord and Orange extension cords at home.  In general for actual stage type play use in a 100 seat or larger theater, you are not allowed to be using junior jacketed cable no matter the type - SJE, SJ, SJT as most but all orange extension cords are.  The NEC makes (at least under my understanding of it) no separation between the rubber like plastic, the rubberized plastic supplemented and the totally plastic type of wire for use on stage or in amperage rating - much less color.  They are all - no matter the color yellow, green, brown, white, blue, black or what ever banned from proper stage usage in the SJ grade as he referred to.  On the other hand as long as they are type S without the SJ following it, they are all permissible for use on stage in jumper cable types but not single conductor feeder cable which is still required to be type SC or W.  SOOW wire in fluorescent yellow would thus be more proper for use on a actual stage than anything SJOOW much less SJTOW no matter the color on a real stage.



That all said, there is an exception for cable supported by truss in conditions other than theater.  Otherwise the maximum length of SJ type cable no matter the plastic content in them is 3'.  I read about such an exception once but am not an expert on Code thus would rely on others to state the exact exemption for stage usage.  This however controversially would not apply to even in a rock concert to stuff used on stage or dropped down from the truss since it's not supported by the above.  In other words, use of SJ cable in general is a large Gray area and one that to the best of my knowledge is either ignored and broken or there in rock/convention use separates it application to it's use by our stage hand brothers.

In any case, Orange, Black or what ever the color, there is no NEC requirement for color that I can discern for use in our industry.  It's very un-professional to be using orange cords, but nothing electrically wrong with it in general given the plugs are also acceptable for your application which is another area of debate.  In general, he is also right in that the thermoplastic type SJT wire will not hold up as well as other cable.  I differ in that it does not hold up as well by way of abuse - all it takes is one cable loom with a stage hand having other than a hook blade utility knife and that jacket no matter the material will be slit.  I don't differ in that rubberized type SJ, SJO, SJOW or SJOOW wire in being rubberized will react much better to heat than any SJE or SJT type.  Plastic melts and drips away when heated.  While all similar cables above have the same operation temperatures, just touch anything in SJE or SJT to the back of a Leko or moving light and it's going to be much more damaged than any rubberized cable.  Granted the rubber won't be di-electrically as strong, at least it's still a barrier between conductor and short.

SJT type orange plastic/thermoplastic/thermoset type cables on the other hand do have a better abrasion resistance to that of rubberized wire.  It on the other hand is by far harder to bond to a strain relief or twofer junction than rubberized materials supplemented by plastic also to prevent bugs, rot and make it cheap.  They all will cut open very easy in comparison to the "Extra Heavy Duty" thick jacket type S materials such as S, SO, SOO, SOOW or SOW material.  Good stuff, but "Too heavy" as most complain.  When it comes to load rating that weight will add up however.  Expect any SJ type will last three to seven years.  The thick cable is heavy jacket and should last 10 to 20 years.

Craig is right in avoiding the Orange cable given it's SJT type, type stuff will melt down when heated exposing conductors.  It's jacket once it gets really cold or otherwise abused won't last as long in general.  On the other hand some vendors do sell SJT pre-molded Edison type plugged cable in this style - just in black.  On the whole there is nothing wrong with it but it's made to a higher standard or grade in general than your 99 cent home owner grade.  The home owner stuff does fall apart readily.  This while usually Euro with it's own standards is what you might find on your IEC type cable such as you have coming off your computer monitor.  Them things when not abused do last.

The next new thing is SJE which is supple like rubber unlike SJT but still plastic.  Many microphone cables and snakes will be made of a similar material.  The at least electrical contracting industry is very much sold on this stuff.  Any questions, contact your electrical supply house and wait for the next sales pitch for SJE over SJ cable.  For the most part, Coleman makes a very nice SJE cable, but it's still going to melt and not be as easy to work with.  It should take heat and cold conditions a little better, but for general usage, it's crap.  Remember the NEC accepts any of these cables by code for their usage equally so if low on budget, SJE might not be a bad solution.

Grade S cable while not really completely rubber any more is the stuff you want to be using.  It's mostly only available in black as a color but often can be found even in an orange color - even the thick extra hard usage stuff as per proper stage usage - remember it's the construction industry that pushes the market and Orange has a value to them at least.  SJ verses S wire is your choice as long as your local inspector signs off on your usage of it.  I supply in stock both types but my intent is a more strict interpretation of the NEC and it is very much not followed by the end users on shows even where I work.  "It's too heavy."  Thus even on a floor that does not at least have a ramp over it, the SJ - junior jacket cable is used even in doorways that are also against code to string thru.  Get a lot of cut SJ cable that were passed thru doors much less cut themselfs on the corner of a truss.  Since our stock is primarily SJ and black, with orange only occasionally and in limited usage, I see lots more of the black not holding up to utility knives or abuse than any orange cable no matter the grade.  SJ cable might seem thicker in jacket to SJT but in actuality, it's resistance and strength is similar.

Does not matter the color, and at least when temperatures are not factored in, the SJT orange extension cords might even hold up to more abuse than a rubberized cable - at least it's not going to rot in a few years like the other stuff.  I have seen the thick jacket type S cable last over 30 years.  On the other hand, SJ lasts about 15 years in the extreme and if lucky.  Given the cheaper over the life price of the Extra Heavy Duty cable, it's more economical to be using anyway, but at least is required on stage.  For truss, the SJ cable is best for our type of "entertainment usage" as long as any cable is 12 AWG.  I say 12 AWG because given most dimmers are rated for 20 amp, and most stage hands don't know amplification tables for extension cords, much less voltage drop, anything 14/3 at 15 amps/1,800w is very likely to be used for larger loads thus potentially melt down or even explode at times.  Go with at least 12/3 S or SJ for all your cable as a American 120v standard.  Much safer.  The 14/3 much less 16/3 stuff will be overloaded and one of the problems with rubberized cable is that it can become overheated without showing a problem, but still loose it's dielecric strength.  On rubber cable if overheated or over amperaged, it's much more possible you won't notice the problem until it is far too late.  SJE has it's advantages in this case.

Hope it helps describe the three types of cable, NEC requirements as I understand them, and what's best to be using in spite of all being Ok or not Ok for usage.

I became sold on the SJE cable for a while in saving about $0.04 per foot over 1,000 and 2,000 foot spools of it.  Hated wiring with it, and in general the cable did not last as long.  I also frequently get in SJT black cables with pre-molded plugs on them without any identifying marks on them that I'm forced to put into my own stock since I can't send them back.  In my case I have the ability to mark them well.  The SJT and SJE for the most part seem to hold up as well if not better than SJ rubberized wire on the whole as long as they don't touch a fixture.  Economically, the price on pre-molded Edison plugs on SJT wire might be well worth it also given the prices such things sell at.  They won't take the heat thus can be dangerous, but for the most part work just as well all around.  I'm back to normal rubber wire now, the SJE did not hold up as well, nor was it as easy to wire, but there is nothing on the whole wrong with it.  Where possible, especially for adaptors and twofers, you might go with grade S Extra Heavy duty in thickness jacketed cable because it will last longer, but after that for rock it's all good.
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