Safely hanging projectors from gym basketball hoop piping.

nickwec

Member
Hi all (first post!)- not sure if this is a post for the projection forum, but I'm gonna stick it here because it's mostly rigging related. For my school's upcoming homecoming dance I've been asked to create a sort of projector mosaic on a white stone wall in our gym; I've taken 6 projectors from our stores and started to go about hanging them.

Here's the setup so far:
http://imgur.com/3EfjtdN

Couldn't find any hardware to mount these guys on c-clamps at first so I went ahead and built frames for them: each is constructed with ply held together with 3-in deck screws at the sides and L-brackets for extra support. The c-clamp apparatus is another ply board with a hole bored for the clamp bolt, mounted onto the bottom ply board with 6 1.5in screws. All in all the mount is held onto the projector with the built-in machine screw mounting points for a normal mount.

First question: will this be enough to ensure that the projectors will stay in place? They're being hung above people so I also plan to safety cable the projector itself to the bar...which brings me to my second question...

Second question: We plan to hang these from piping used for ceiling-suspended gym basketball hoops, with no more than 2 for each set of pipe. How will the clamps do on the pipe? Is the pipe even remotely safe to hang from? I've been up on a genie to check it out and I can't find stamping on it anywhere, but it seems completely stable.

Sorry for the long read, want to get this right and safe.
 
I can't download the picture since I'm at work, but
...will this be enough to ensure that the projectors will stay in place?
is a question that only you can answer. If you're asking that then you probably need to have a set of professionally trained eyes on this. Hanging from the basketball apparatus is questionable. I'm guessing that manufacturers of hardware like that will have an engineer determine attachment points to the roof and the proper bracing needed to sustain a basketball goal with what I would guess is occasional dynamic loading from the ball hitting or the occasional dunk. That being said, do you know what the load bearing capability of that structure is? If not, how can you be sure you're not exceeding it by hanging off it? A projector is relatively light, but it will still hurt/injure if it were to fall.

Please consider finding a rigger in your area (there are a few New Jersey people on here) to come put eyes on your plan before you rig it up.
 
Nickwec, whats preventing the projectors from sliding out? What model projector are they. They might have an actual hanging mount. Remember anytime someone says homemade and hung above someones head that puts all the liability on you. This a homecoming dance, there will be lots of low end. Things will vibrate. Things will come loose if any of those things is in this system. Its now your fault when it hits someone.

I Caution anyone who wants to hang a projector but doesn't want to pay for the rated and manufactured hanging brackets to not do so without them. There is a reason they are expensive, they've been tested and rated.
 
Duck, He did mention that his mount is held onto the projector with the built-in mounting points. I also can't tell from the picture where the fan and vents are but I'd caution that if your bracket covers them you should look for a different way of mounting, to keep the air flowing.
 
Vents are located on the sides of the projector- there's at least a quarter inch clearance between the wood and fan vents. In terms of the low end shaking the pipe, I'm not sure how much that would effect it, but since I'm also in charge of sound (I'm sort of a jack of all trades at my school...eh) I could put the main speaker setup somewhere where the vibrations are at a minimum (we use portable JBL towers).

The projectors are InFocus model IN2116. They've got 3 built-in mounting points that I'm using with machine screws to attach my boxlike clamp mount to the projector. I chose a box design so that if for some reason one of the built-in points fails, the bottom of the projectors will still be supported + won't fall.

Thanks for the quick responses, btw :)
 
We make a PPM1 projector pole mount which can easily be adapted to terminate in a steel pipe with standard C clamp or O clamp.

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Thanks Bill, but since this is a one time thing (and therefore my budget is quite low) I think that's a little out of our price range. I appreciate it though; more looking for advice at how to make a DIY mount as safe as possible.
 
Do they have to hang because that is a big ouch if it falls and it is just held together with some 1 x 4 s and 1" angle irons someone is going to get thrown under the bus.
 
Do they have to hang because that is a big ouch if it falls and it is just held together with some 1 x 4 s and 1" angle irons someone is going to get thrown under the bus.

Not just angle irons, also two 3 inch screws on each angle. It's built very sturdy and I'm less worried about it "falling apart" in the air than I am with it just "falling".
 
Ok... here we go...
  • Depending on the size of pipe used odds are your clamps won't fit over the pipe. I have hung fixtures off of basketball nets before, it is usually 2" pipe instead of 1.5"...
  • Are these movable/retractable nets or they the kind that can be cranked up out of the way? if so, what configuration are they in?
  • As far as the mount goes, I don't like it. First, plywood is not designed to be screwed into from the side. It tends to pull the lamination apart and weaken the whole thing. Your angle "irons" (that is not angle iron) is only making one screw on your top plate... which makes it pretty useless.
  • I assume you glued it...
  • You left yourself NO way to focus it
  • I'm concerned about heat if you only left yourself 1/2" of clearance
  • Are you overhanging or under hanging these?
I would not hang these as is. Jump up to 2x4 or 2x6 and we'll talk. If you are going to use wood, use some wood with some real meat. Plywood is great and all but as a structural piece it falls short... it works until it doesn't and when it doesn't it blows apart. Do you have a shop class? Does that shop have a metal shop? Walk down there and see if your shop teacher can help you build something a bit more robust. After that, then have him/her help you decide if what you are hanging from is safe to hang from.
 
Do you have a shop class? Does that shop have a metal shop? Walk down there and see if your shop teacher can help you build something a bit more robust. After that, then have him/her help you decide if what you are hanging from is safe to hang from.

Along those lines, usually the main component of those mounts is a piece of triangular sheet metal (I'd recommend 1/8") with holes drilled at the appropriate points. From there, you could figure out how to mount it, whether it's running the clamp directly through the mounting plate or building some other type of bracket. I would make it as simple as possible. If you added spacers to raise the plate about 1/2" off the projector's bottom (using long enough machine screws to account for the difference), you could fit a yoke bolt in there and hang it that way. Add a hole to run a safety cable through, in addition to safety'ing the projector.

@Footer raises a good point about the pipe thickness. I'm sure it depends on the brand and portion of structure, but the ones I've seen appeared to use 2"OD pipe (probably thin wall). That said, I've never been very close to one. What's the ceiling of this gym like? If it's exposed girders, you could use a beam clamp.

I'll echo the sentiments about circulation while I'm here. These small projector fans don't move a lot of CFM's due to needing to be so quiet, so they really rely on not being "hugged" by anything. The body kind of acts like a big heatsink.
 
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I am merely commenting on question 2 as I feel several good answers/issues have been given relative to your first question. This also assumes your clamp will fit on the basketball hoop pipe.

I think it's safe to assume that the pipe is sturdier than your mounting apparatus. That being said, I would do my best to safety directly from the projector to the hoop pipe (or if you have a lot of SWR the structural beam above the hoop) . No matter what rigging you used, the rigging is likely to be the weakest point in the system, and as far as safety goes I would plan for the whole system to be held up by the projector itself (many lighting fixtures have an integrated safety point, hopefully your projectors do too).

Going beyond your immediate concerns, this may be a one off with a relatively low budget, but if your school is going to continue to want to use projection for events in this space (hopefully what happens when you do this and it works well) it might me worth it for your school system to invest in a proper mounting system. Schools are notorious for recycling what works once whether it's safe or not, but in the long run they may not have a student willing or able to build custom frames to mount the projectors safely. One big oppsies in a custom frame means at best a projector that will never work again, and could be a serious danger to the people below. If this is something that you or your teacher foresee happening more than a few times in the near future I'd ask for proper mounts. It may seem beyond your program's budget, but honestly if you asked your school district's insurance company for permission to use student built mounts to hang equipment overhead they would almost certainly tell you no.
 
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No rigger here, but very good carpenter. It looks like your build is potentially solid - that being said, the design worries me. If I am reading correctly, there is less than 3/8" of bored plywood holding the pipe clam bolt. Any lateral pressure (ie: someone yanks the cord, big gust of wind through the door, or "the whole room gets a bouncin'") and that bolt is likely to break through the remaining material.

I hope the dance goes well!
 
@Footer, no shop class, but there is a set shop that I'm working out of -- metalwork is a no, and we're mostly equipped with a bunch of plywood considering it's the beginning of the year and our stores haven't been restocked yet. Also the focus knob is still exposed -- I can reach it just fine.

@AudJ, I thought about that as well...any ideas about how to reinforce/replace that board?

I'm certain the pipe is standard 1.5". I spoke with the school's dean of students and she is going to call an engineering company that consults with the school (which I should mention, is private) to ask about the pipes.

I'll take another look at the materials we have and get back to you all.
 
OK, quick update.
The bars in question are rated to hold more than enough weight for a projector, according to the engineer.

That is great, good working getting that checked on. I would still rather see a piece of 1/8 plate steel with a clamp attached to it then what you have now. Basically, do what Les said.
 
I'll head to the lumber store in my town to pick up some plate steel today. Hopefully I can use maint.'s circular saw for the cuts.
Any idea how I could go about boring holes through it @Footer ? I doubt a normal power driver would get to job done. Never worked extensively with steel before.
 
I'd recommend a jig saw with a metal blade in it over a circ and yes a power drill will work fine to make your holes you can either get a straight bit ( for metal) or what I would do is get a diamond carbon step bit so you can counter sink into your plate. So you screws are flush on the plate. Just my opinion.
 
I'll head to the lumber store in my town to pick up some plate steel today. Hopefully I can use maint.'s circular saw for the cuts.
Any idea how I could go about boring holes through it @Footer ? I doubt a normal power driver would get to job done. Never worked extensively with steel before.

Odds are you can buy the steel in the size you need... or at least close. A drill press is preferable, but a standard drill will work. Be sure to clamp down the steel. Be sure to center punch the place you want to drill... a nail will work to do this in a pinch. http://www.wikihow.com/Drill-Steel.
 

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