Mounting lights to shine upwards


Benevolent Dictator
Senior Team
CB Mods
Fight Leukemia
I want to create a movable floor mount that will hold 2 Source 4's. I want to be able to shine them upwards and outwards from the back of the stage as part of a potential design I'm working on. Oh, the only major requirement is, I can't attach it to the floor (not allowed to dril anything into our stage)
There is not a boom base available. What I'm thinking is a wood and/or metal frame that has a bar on it that up to 2 lights can clamp on. It needs to be portable, (so maybe have some removable ballast, or a non-tippable design?)

The entire support has to fit inside a 2' x 2' square.
I must be missing something here. Why do you have to use the C-Clamps as in a boom base or side arm situation? Why not just bolt the yoke directly to your plywood or steel floor base? Could even put a washer under it if you want the ability to adjust it - especially if it's a fiber or nylon washer that won't let you tighten the bolt tight enough that you still can't adjust the fixture. Most Lekos are yoked at their balance point so as long as you have enough weight and square inches of material below them to counter balance any tipping or top heavyness of the fixture, you don't need to attach them to pipe or steel as if they were flown over head. Consiquently, most floor bases are more than sufficient in weight to support the Leko. I would put both on individual floor bases. Much easier to move.

If necessary, lay down some gaffers tape and install some velcro above it. The gaff tape will come off the stage without marring the surface, the velcro will be able to stick to your floor base, ensuring it won't move. Another option is to use stick on or screw on rubber feet under the base to prevent it from sliding about when weight such as the weight of an instrument possibly with a small stage weight or sand bag supplimenting it. If necessary, install your hole slightly off center to counteract any weight distribution issues. After that, I have seen larger plywood bases that would easily adapt to a smaller scale with vinyl floor runner/non-skid materials on it for stage braces, a few sand bags thrown on the plywood to keep the wall in place without marring the floor. Wouldn't take much for a Leko.

Here are some options that I have used when painted black:

Option 1, use a commercially available room dividing industrial show/party pipe and drape portable steel or aluminum base. They vary from 12 to 18" in size and have countersunk holes in them to accept a 1/2" flat-head screw. (Your maintinence departmant might have a few they can loan out. They are usually either steel plate or molded and countersunk plates of a thinner gauge.)

Option 2, use a mic stand base, a 1/2" screw and some washers. Since it's tapped for a 3/4" NPT hole, and you will be using a 1/2" bolt, there isn't much chance you will be stripping it out but if necessary, you can add a pipe spacer of some sort say a 1/2" Sch. 40 pipe or better yet a small section of 1/2" RMT pipe to fill the gap. I usually don't worry about it however.

Option 3, get a piece of plate steel say 1/8" to 1/2" thick and usually 12" square and countersink two 1/2" holes in it. One at the center and one towards the front. If using a smaller plate, you will need to epoxy or weld a block or at least 1/4" plate to it to accept the countersunk bolt. Install some female velcro on the bottom so it doesn't scratch the floor. Could swipe a stage weight and countersink a hole to it also if you are not afraid of pissing off the TD. That's about double the weight you need. On the same idea, I have used some 10" x 1/8" plate with a small handle like section of 1.1/2" Sch. 40 pipe welded to it by way of a joiner plate between the two. That way, if you are really attached to using a C-Clamp, you just clamp to the handle part.

Option 4, laminate together 2 pieces of 3/4"x12" square particle board. Router the edges as needed and countersink a hole for the bolt. Cut the above holes in it and install rubber case feet on the bottom.

Option 5, do the above with plywood either plywood squares or disks. This is a light weight option so if you need to install both instruments, they can be both on the same base. Just a question of installing a block on the plywood so there is enough thickness to hold a screw. If you want to use normal hex bolts with this option, just fillet a hole in the bottom board.

Option 6, Get some 7/8"x1.5/8" slotted Unistrut in an appropriate length. Attach some at least 3"x6" x 1/16" plate to the ends (if not plywood) and center to act as feet, or attach some unistrut for this purpose. Use Unistrut nuts to attach the fixtures to the Unistrut.

Option 7, Same as above but with at least 1.1/4"x16ga box tubing steel or 1" Sch. 40 Pipe with the fixture bolted instead of clamped to the pipe or tubing.

Option 8, use Sch.40 Pipe (Steel Lighting Pipe). Rotolock legs/outriggers to the pipe using floor flanges and 90 degree plumbing joints. Than clamp to the pipe using anything from baby clamps for 3/4" pipe to normal C-clamps for normal 1.5" ID pipe.

I must have missed something. Look about, I'm sure floor bases for lights are around the theater somewhere or put a bit of thought and time into them and give the theather something they should already have about.
Well, we definitely don't have any lying about... (This theater is only three years old and we are just starting to get a usuable amount of equipment together)

But the options you presented are more than enough to get me started... Just need to figure out which solution will work best for our stage.
Need any details on making them?
I'm sure that would be a lively debate on the proper way.
thanks for the smile. Just got braces today on the lower jaw and can use a laugh. Spent 30 some odd years thinking annoyance was just what someone gave you or the effects of combat boots on marching but getting a lot of later life work done on the teeth is a whole new form of torcher.

What us debating the "proper way" on something? That's our purpose in life, Ying and Yang, Punch and Judy (you are Judy.) Without sparring with each other and the debates on the merits of long messages, where would the spice in life be?

Lots of ways to make a floor base. No one best way. How do you do it? Let the games begin.
Okay I guess I'll start with the sympathy for the teeth. I too am currently in the process of having my mouth re-done. Of course the one thing that is right with my teeth is they are straight, so I get to avoid braces. I am on a three year plan, first year fillings (20+), extractions (5), now I am looking into bridgework. So a word to the youngers, Take very good care of your teeth.

Now for the light base, my vote would be for a 3/4" ply 2'x2' square, framed out with 2"x4"(to allow plenty of room for bolts and add more weight for counterbalance), than to the center of the ply bolt on a 2" pipe flange (I believe that is the right term), Than take a threaded piece of 2" pipe about 24" long and screw it into the flange, than I would use either sidearms or just the C clamp(depending on the focus needs) to mount to the pipe (this should alllow plenty of focus room). And to avoid a messy accident I would suggest mounting a weight to the underbelly, but a sandbag on top would work fine too.

Now that that is said, all of Ships suggestion would work very well too, some better than others but all viable solutions depending on what supplies you may have.

How'd I do?

"So a word to the youngers, Take very good care of your teeth. "

Yea, we both have the same opinion. 4 extractions so far, 2 implants as soon as the lower jaw is in place and two on a bridge, than next year comes the lower wisdom teeth that grew in sideways and into the bone. Lots of fillings - 10 years without dental insurance.

I whole hartidly agree with the take care of your teeth idea.

In college, I put in a lot of hours and became edicted to Cokeacola and brushing when I had time. After school, while still edicted I spent too many hours on stage and not enough in personal time for things like doctor's visits or brushing. Hard to consider doctor's visits when you are choosing between donuts or a $2.00 burger with assorted bones and other cheap meat in it, coming with fries from the local diner in the slums for dinner and scraping pennies to afford even that. Much less affording a doctor. The better you keep up your mouth, health and credit rating when you are poor, the less it will cost you later.

I would put some carpet or some rubber under the 2x4 lumber, or at least ensure none of the screws tips pop or it can scratch the floor. I would also glue the assembly for strength.

As for your boom base as it were, 2" pipe is a bit larger than standard, remember water pipe/black Sch. 40/gas pipe as well as conduit is measured by the nominal inside diameter not the outside one as I think you were referring to. Only structural steel and aluminum such as used with truss is measured by the outside diameter. 1.1/2" sch. 40 pipe is more standard for theater and boom bases. The term "schedule" is an industry standard referring to the thickness of the pipe's wall. Doesn't come in much use at Home Depot because they refer to PVC pipe as Sch 40, but it's the same thickness thus you need to say black water or gas pipe. Avoid galvanized and RMT or ridgid metallic conduit/tubing pipe, they are not rated for use on stage. 2" pipe is only used on some old stages as batten pipe. Most modern J-Clamps or other types won't even mount to it. If you want extra weight as ballast you can get sch 80 or sch 120 pipe with their thicker walls. Sch 80 is available from plumming supply shops, 120 is difficult to get and officially as per the Backstage Handbook, is designated as batten pipe. I build my side arms out of Sch. 80 pipe. Much stronger and resistant to bending.

Floor flanges are probably okay for a 2' pipe sticking out of them but are highly frouned upon for use in other applications. They are cast and without load rating. Use of them for anything but this specific use with that length of pipe is dangerous. You would be better off using a flange designed for this purpose should you wish to use the boom base as described with longer pipe or it can break easily. You could also have a coupler welded to a 1/4" x 6" square plate and it would be stronger.

An even easier idea would be to use EZ-Rail or Key Klamp type fittings that use a set screw to retain the pipe instead of requiring threading the pipe into the fitting. I'ts load rated but not as a boom base so it's not the best option either. Easier if you don't have pre-threaded and un-dinged pipe however.

I still think a floor base with fixture directly attached to the base and at the yoke is the better option. Smaller in square area and weight, plus it would be easier to remove. Also, unless you are using 7-ply 3/4" plywood, it probably won't last that long with abuse. Too much flex to it even if blocked in the center. Another option would be to use a laminated layer of 1/2" plywood with 1x4 lumber at the bottom if you didn't want to countersink the holes for the screws. 5-ply 1/2" plywood would be nice but at least with 3-ply you would get 6 laminations of cross grain and a little more weight. Still Altman boom bases don't sell for that much money and are rated for use as booms as opposed to a plumbing floor flange as the weak point.

Remember once the thing is built, it probably won't be taken apart and will eventually be used as a misguided boom base.
Yeah my bad on diameter. You got me there.
As for gluing, I understand that some educational settings have very limited finances. But I would have to say glue as much stuff together as possible. As well as using screws or staples or brads... Glue is an amazing substance and it really does wonders for structural integrety.
As for ply I didn't realize I had to be that specific Ship. Of course 3/4" 7 ply and as for attaching the flange I would drill all the way through and bolt it together.
And I agree this is one of those things that there are a bunch of different ways to do it. I just decided to throw one out that you didn't mention. I agree that just mounting the yoke to something is the easiest way. But without knowing exactly what the focus has to be, I just thought I would thorw another idea that allows total focus. Where as mounting two source 4's in that tight of space can cut some of the options out.

Off to brush and floss.

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