# How to hang a FPTV with Unistrut



## kal

Back in Dec 2000 I saved these instructions off of another forum member's web site. Since then that site has died so I've had a lot of requests for these instructions. To make everyone's life easier I figured I'd simply repost them here!

*Please remember that this was not originally written by me, so I won't be able to answer specific questions about why a certain decision had been made. This *is* a strong, reliable, cheap, and most importantly flexible way to hang a FPTV. Though personally I feel that he used waaay too many lag bolts. 2 to 4 (instead of 8) per piece of unitstrut should be more then adequate.*


WARNING: Be careful not to use magnetized unistrut as it may contort the CRT rasters in funny ways. To make sure, wave a 1-2 foot piece of strut near the tubes while displaying a grid pattern & see if the grid warps at all...


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*How to hang a FPTV with Unistrut*


OK, first - I apologize for the crude images. I am still building the rest of the theater (and basement), so the projector is covered.


Parts list:


* 15 feet of channel strut ( called Unistrut, Superstrut, and Powerstrut most commonly).

* 24 lag bolts - 4 inches long 3/8 inch diameter, with washers that are sized to fit in the channel (less than 1.25 inches in diameter). Good luck finding the washers.

* 5 feet of 3/8 inch coarse thread rod.

* 30+ washers (normal 1.5 inch washers) for 3/8 inch rod.

* 10 strut hangers.

* 30 3/8 inch coarse nuts.


Total Cost of Parts:


* About $40. You can't beat the price, considering most OEM mounts are over $200 and don't have any flexibility.


Step 1:


Find the optimal distance from the screen to where you want the projector mounted. Decide how much play you want in the mount (by play I mean - how much do you want to adjust the unit once you have it mounted). Once you have decided how much play you want in the mount - you can cut the first pieces.

http://www3.sympatico.ca/vwallner/1S...ectormount.jpg 


The pieces you are cutting will go on the joists themselves. If you are going parallel to the joist (as pictured above) you could get away with only 2 pieces, but take the extra time and use three - you'll feel much better in the end. If you are going perpendicular to the joists then please mount a piece of 3/4 inch MDF onto the entire area of you mounting and then mount the strut through the MDF into the joist and where you have no joist - mount directly to the MDF. If you want extra play in the distance of the projector (moving the unit back and forth) then cut your strut so you have extra space left over to slid the projector front-to-back. As most people never get the distance exactly right (as you MUST if you use the manufacturer's mount) this is a great way for you to approximate the optimal distance. Then, once you setup the images on the CRT faces to get the most of the raster size - you can move the project to the "perfect" sweet spot for your screen.


Step 2:


Bolt on the strut. You will want to pre-drill all your holes - at least to a depth of 3 inches. I used 8 bolts per strut and 2 washers per bolt. Take your time on this. You are going to want to ratchet the bolts in as fast as you can, but please don't. The bolts are going to get VERY hot and can snap if you just twist away. Take your time and do this one step by hand, don't use a gun. If you snap a couple of bolts your gonna get ticked (learn from my mistake here).

And while I'm talking about bolts - please buy quality bolts. Go to a Home Depot or a Lowes, whatever you have, just don't go to the local ACE Hardware, or True Value - the bolts they sell are junk (sorry, but they are, I snapped two out of three from each of them when I was testing them out).


Step 3:


Now that you have your strut mounted to the ceiling, you are ready to cut the mid pieces. These pieces go between the joist mounted strut and the projector bracket.

http://www3.sympatico.ca/vwallner/2R...ectormount.jpg 


This piece only needs to be as wide as the pieces you have mounted to the joists. Any longer than that and you are looking at headaches on building the enclosure later (hush boxes are enough of a pain to build under the best conditions - don't make it any harder on yourself).

Once you cut this piece, make sure to knock the burrs of the edges - they will slice you right open. OK, now the hard part. Calculate the height you projector needs to be at and take into consideration the distance that the projector is going to hang below this layer of strut. You will be able to adjust this ~2 inches up or down later, but do try to get it right the first time. Now cut the 3/8 inch coarse rod for all 6 pieces - 3 in front and three in back. the rod in the following order (top to bottom): Strut hanger, washer, bolt -space- bolt, washer, middle piece of strut, washer, bolt. (There is a really good close-up picture of this below, so don't worry if that makes no sense right now). Attach all of these as shown above and then you will have 2 pieces of strut with three bolts sticking out the top of each. You can now place the Strut hangers in the top channels of strut and slide them into position. When you are done you will have three struts attached to the ceiling joists, with two struts hanging from them by 6 bolts. At this point give it a test - have some friends come over and hang on them, try to use them as a pulley and lift something ridiculously heavy (other than your projector).


Now...


Step 4:


Attaching the projector to the hanging strut is very easy, provided you have enough strong people, or a way to lift the proector into position and slide it onto the strut (drywall lifts don't work well at all - they are usually not rated for the weight and they tend to flop back to vertical). I personally built a platform to set the projector that was 4 inches below the strut so we only had to lift it up onto the platform once and then slide it into the strut.

http://www3.sympatico.ca/vwallner/3C...Mount-Side.jpg 


You use the same sequence of hardware as you did to mount the struts together (this picture shows it very well). When you are done, you will have a projector with bolts sticking out the top of it. All you need to do now is slide these strut hangers into the lower piece of channel and you are done. You can then adjust the height of the projector by adjusting the length of the bolts between the struts.


Hints to getting it right:


1. Take your time on the lag bolts.

2. Make sure that when you hang the lower strut that you have room INSIDE the strut channel to slide the strut hanger that is attached to the projector. You don't want to find out that the projector's strut hanger can't slide because the rod attached to the top of the strut is poking down too far ( especially if you are currently holding the projector over your head). Or, you could mount the projector by lifting it straight up and twisting the hangers into the channel (impossible if people are lifting it, but EASY if you have a mechanical lift).

3. Get all the distances as accurate as possible to begin with. This can save you a great deal of time later. Just because you

can adjust it as much as you want later, doesn't mean you should be sloppy in the design.

4. While you can adjust the height of the mount up and down, you can only easily adjust it up (see Hint #2) after you have the project fully mounted.

5. Be careful of the strut hangers, they can twist and come out of the channel, that is why I put a washer and bolt below them, when you have the perfect spot, tighten the bolt, the pressure of the bolt onto the cone will lock it into place. If you don't like the fact that they can twist out - look into getting "concrete nuts". They are perfect brass squares that fit in the channel and DO NOT rotate, but they are slick, while the hangers are grooved. Pluses and minuses to both - it is your call.


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Hope this helps someone!


Kal


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## Chris Williams

You might also check out the renderings I did of my UniStrut approach. It will only work on a CRT that has a flat area on the top like the Sony 12xx series.


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## wolf

I like your technique of using unistrut to hang a projector. But, I have to quibble with your advice about lag bolts.


From your description, you were almost certainly using the lag bolts improperly. A typical lag bolt is made with a metal having an average tensile yield strength of 45000 PSI. This is much stronger then the wood you're fastening the lag bolt into, and much stronger then the pullout strength provided by the bolt. For the size of bolt you used, a power driver shouldn't cause any problems. Your report of some brands of bolts not having a problem is probably due to them being made out of a 125000 PSI metal instead of a 45000 PSI metal.


You probably made some combination of three mistakes when using the lag bolts:


1) Lag bolts should be driven into pre-drilled holes that run the full depth the bolt will occupy. You said to drill "at least to a depth of 3 inches" for a 4 inch bolt. You should pre-drill the full 4 inches.


2) Many people drill a pilot hole that is not wide enough. For douglas fir or southern pine, the pilot hole should be 60% to 75% of the lag bolt's shank size. So, for your 3/8" bolts, a 1/4" drill bit would probably be appropriate.


3) Lag bolts should be lubricated before you drive them in. A bar of soap is an appropriate lubricant for your purposes.


The really critical mistake to avoid is using a short pilot hole. Lag bolts are not designed to create their own hole. When you hit the end of the pilot hole, the bolt may turn in place some, thus shredding the wood surrounding the threads, and dramatically weakening the pullout strength of the bolt. Excessive heat could be a sign that this is occurring.


The US government's Forest Products Lab website at www.fpl.fs.fed.us contains detailed discussions of proper use of wood fasteners for those who desire more info.


-Michael Wolf


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## stefuel

I'm scared. If I'm seeing the correctly you are putting lags or shields into the edge of the joist? This will split the joist over time. You can buy joist hangers for threaded rod that bolts through the joist on the flat side that will never come down. The threaded rod threads right into the joist hanger and gives you all the adjustment up and down you should need. Before you cover it up I would pick up a roll of that metal strap material with the holes in it and go around each corner up as high as you can go on the joist and bolt through it as a saftey measure. When the joist splits the tension on the lag is lost. Guess what happends next?


Chip S.


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## wolf

You shouldn't be concerned about inserting 3/8" lag bolts into the thin side of a joist, as long as it's a solid wood joist of 2-by-whatever size, and an appropriately centered and sized pilot hole is used.


It is true that the max pullout load of a lag bolt is lower then max lateral loads, and an appropriate attachment to the side of a joist would support a larger amount of weight. But, the lag bolts should provide more then enough support to hang a projector. Kal specifies 8 lag bolts for each of 3 pieces of unistrut. 24 bolts total! Talk about overkill. I consider myself paranoid when it comes to structural engineering, and I used a total of 6 lag bolts to hang my XG135LC, and they were only 1/2" bolts.


According my wood handbook, a 3/8" lag bolt inserted into the side of a piece of douglas fir will have a max pullout strength of 2873 inch-pounds. Even with a factor of 5 safety margin, the bolts should be strong enough to hold a projecter even if 2 out of the three joists fail.


Many people will wish to mount projectors without tearing up the ceiling to get at the side of a joist. I hope my figures convince you that one can safely use "edge" mounted lag bolts.


-Michael Wolf


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## gn2

Thanks Michael, its really nice of you to take the time to give a concise, fact based reassurance. Very good additions to the Unistrut instructions.


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## rorox64

I normally use Unistrut with a couple of L pieces for each bolt, under the pj, the way you're explaining allows to mount the pj at a different distance, from the ceiling!


ciao

Romano


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## Steve B

I agree with Michael Wolf (until my G70 falls from the ceiling). To test the 3/8" bolts I placed, I bolted a board to the 2x10 "on edge". With a single 3/8" bolt (with a properly predrilled pilot hole), I was able to do pull-ups with no movement of any type. I weigh approximately 175 lbs and was not putting even lateral side pressure at the time. Based on that, I figured the 9 bolts I put in 3 pieces of unistrut was overkill, but better safe than sorry. Every bolt should be able to hold the weight of the projector - 170 lbs (since it held me), but they each only need to hold approximately 30 lbs.


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## lee jordan

Michael, what are you using to mount your xg? Curious as I'm weighing whether to buy NEC mount or attempt some fabrication for my xg. Any suggestions. Can e-mail me at [email protected] thanks


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## kal

Hi guys!


Good information here! I originally reposted these instructions from someone else (I'm not the original writer FYI), and tend to agree that 24 lag bolts is extreme overkill.


With 3 bars, instead of using 8 lag bolts per bar, 3 would probably suffice. Especially when you consider that the unitstrut is then connected to the projector using only 4 bolts!


Kal


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## wolf

It's getting a little off topic for this thread, but I thought I'd post about my xg135lc mounting here in case others are interested in my response.


Lee, my setup called for mounting the projector directly on to the ceiling. I didn't need to suspend it beneath the ceiling as occurred with the original post in this thread.


So, I obtained the standard NEC metal mounting square. This is a rectangular metal mount, 6 5/8" by 16 5/8" by 1 15/16", along with two metal mounting brackets. I assume this mount is available from the dealer that sold you the xg135lc. NEC's intent is to screw the brackets onto the projector, attach the mounting square to the ceiling, and then the projector quite simply hooks onto the mount via the attached brackets. So, the only question is how to attach the mounting square to the ceiling.


The mounting square comes with 4 holes of 1/2" diameter that can be used to bolt the mount onto a surface. My ceiling has 16" on-center rafters covered with 1/2" plasterboard. I obtained a 3' wide piece of 3/4" thick plywood, which is wide enough to span three ceiling rafters. I drilled four 3/8" holes in the plywood to match the holes in the ceiling mount, and then bolted the mount on to the plywood with 3/8" bolts and matching nuts and washers. Next I carved four holes into the drywall on my ceiling using a box cutter knife, which the four bolt heads can recess into, thus allowing the plywood to sit flush against the ceiling. I then used a stud sensor to locate the rafter centers, and attached the plywood to the rafters with two 1/2" lag screws (aka bolts) into each rafter. That's all there was to it! The only hard part was trying to make sure the ceiling mount was properly aligned with the wall I project towards, as this low end mount isn't really adjustable. Of course, lifting the projector was also no picnic.


Note that a lag screw doesn't develop maximum pullout resistance until the threaded part is sunk about 7 times the shank diameter. So, for a 1/2" lag screw you need to put about 3 1/2" of thread into the rafter, thus requiring another 1/2" to clear the plaster board, and 3/4" inch for the plywood, for a total bolt length of 4 3/4". As that's an odd size for a 1/2" lag screw, most people will find it easier to buy a 3/8" lag screw of the appropriate size.


Also note that plywood doesn't have the world's highest "punch through" strength. So, where I had bolt heads or lag screw heads up against the plywood, I used fender washers to spread the load out. This is probably my paranoid overkill. For those who don't know, a fender washer is just an unusually wide washer. Normal washers are usually sized to be only marginally larger then the bolt head, and thus don't spread the load out much. Fender washers aren't really designed to carry much load, so this approach isn't a good idea for anything that actually puts high pressure on a bolt.


Also note that I didn't worry much about aesthetics, as my projector is mounted in my garage, and projects through a wall into a viewing room, so the mount goes unseen by most people. However, by sizing the plywood to make it symmetric around the mount, and then appropriately finishing the wood with paint to match your ceiling, I think this could be a fine mount for an interior room.


-Michael


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## stefuel

I hate to keep sounding like a jerk here but here we go again. Wolf, your's scares me even more. Sheetrock is cheap. Some of you guy's are spending big bucks buying these beautiful projectors and about $20.00 hanging them up. Cut that damn sheetrock out, a whole sheet. Get in there and know for sure that your mount is secure. Use L-shaped brackets to attach your uni-strut to the joists/rafters through the sides, up high and not through the edge of the wood. Take your $20.00 add $50.00 more along with 2-3 hour nights work will result in a bullit proof base from which to mount your pride and joy. Wolf, you used a stud finder to locate your wood from which you bolted your mount to. I'm pretty sure California building code requires strapping between the joist/rafter and your sheetrock. When you begin to have unexplainable drift in your projected image (keeping the image on the screen), check that the ceiling in your garage is not falling down. I could be wrong, but I think you've attached your mount to the strapping which is installed with 8-D brite nails. I wish a full time installer would chime in on this and comment? For the record, I'm a licenced heating contractor. If I used some of the methodes mentioned here to hang a residential furnace, a building inspector would throw me off the job.


Chip S.


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## pjenkins

Chip,

Can you post pictures or describe in a bit more detail what you consider "best-practice" for doing such a mount? I have been reading/posting for a couple of days and working with different sketches to figure out how to mount my XG85 with the following goals


a) give the projector no chance of falling!


b) make the projector as level as possible everywhere. If it isn't level, the rest of the setup will be very difficult.


c) allow easy adjustment of the projector in the x/y plane [forward/back side/side]


d) not make it look ugly when it is done. I don't mind the projector coming down from the ceiling for now, but I don't want to be able to look up and see bolts/sheetrock cutouts/other indications that a complete amateur did it..


my situation is that the ceiling/room is complete, and I'm adding the projector to it. My joists go horizontally across the top, so my current thought was to get a 64"+ unistrut and have it span 4 rafters, bolted into each on the 2" bottom. It sounds like you do not advocate that approach???


Thanks,

Paul


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## Vince_B

Ok, I don't have a crt (yet) but I am comfortable with mechanical things, and IMHO:


1. 6-9 lag bolts would be totally adequate. All precautions above about how to install them are totally right-on. I would drill a pilot exactly the same size as the shank of the bolt, you know, the center part that's solid. Get a drill the size of that inner shank without the threads. The threads should bite the wood only. Soap the bolts for sure to make it easier to install.


2. You should center the lags in the studs through the sheetrock. you can easily do this by tapping a finish nail through every 1/4" or so and find the very center of the stud.


I saw a pj fall, or rather it hit the floor above me. We were working in a nightclub one day. We had earlier commented that the pj was very precariously mounted, with the proper mount but not at all secure. So bad that I told my crew to stay out from under it. Later a bar employee walks through with a tall ladder and just taps it, and the thing hit the floor from about 10 feet up. It was amusing since it didn't hit anyone and they were very upset about the projector, and commented that it would cost a fortune to fix (yeah right). Any idiot could tell it was in real danger of falling; they were damn lucky it didn't hit a disco freak in the head. I was directly below it but one floor down, and when it hit I thought part of the building was collapsing


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## J. L.

After reading all the discussion about safety and lag-bolts, I decided to use three "L" brackets and bolts to secure each length of my unistrut to the floor joists. I'm going to use 3/8 inch bolts through the center of each joist.


I found very strong "L" brackets in Home Depot near where they had the unistrut on display. The brackets are made of 3/16 inch thick steel. I have no worry about them being able to support my projector safely.


I should get the unistrut mounted to the joists in a day or two. For now, they are simply resting on top of the projector. Attached is a picture.


Joe L.
_Building a custom projector mount from unistrut is a lot like working with an erector set when I was kid, only with much larger nuts and bolts. (that should date me)_


PS.

The recliner in the background is a BarcaLounger. Just one letter off for a "Barco Lounger"


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## pjenkins

Quote:

_Originally posted by J. L._
*After reading all the discussion about safety and lag-bolts, I decided to use three "L" brackets and bolts to secure each length of my unistrut to the floor joists. I'm going to use 3/8 inch bolts through the center of each joist.


I found very strong "L" brackets in Home Depot near where they had the unistrut on display. The brackets are made of 3/16 inch thick steel. I have no worry about them being able to support my projector safely.


I should get the unistrut mounted to the joists in a day or two. For now, they are simply resting on top of the projector. Attached is a picture.


Joe L.
Building a custom projector mount from unistrut is a lot like working with an erector set when I was kid, only with much larger nuts and bolts. (that should date me)


PS.

The recliner in the background is a BarcaLounger. Just one letter off for a "Barco Lounger"*
JL,

I saw the same thing today in Home Depot and am going to do the same thing. One question, how did you cut the Unistrut? They said hacksaw at Home Depot, I thought I'd buy a metal saw blade and use a miter saw...


Paul


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## J. L.

Paul,


I think it would take a long time to cut through unistrut with a hacksaw. (and probably more than one blade before you were done) Instead, I used a metal cutting blade in my circular saw.


The blade I used is more like a thin fiberglass reinforced grinding wheel than a saw blade. It grinds a 1/8 inch slot through the unistrut accompanied with lots of flying sparks. (do it outside, and make sure you use safety glasses) Look for this type of circular saw blade near the other circular saw blades in your hardware store. It took several minutes to cut (grind through, actually) each piece of unistrut. It is typically advertised as being able to cut through almost anything.


I used the same metal cutting blade to cut through the 3/8 inch threaded rod. I took about 30 seconds to cut through one, but... I think it would have taken much longer if I had used a hacksaw by hand.


Like an earlier poster, I used a file to remove the sharp burrs from the cut edges.


Joe L.


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## pjenkins

Joe,

Thanks for the confirmation, when they said hacksaw I thought he was joking


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## Steve B

I used a hacksaw and it took approximately a minute to get through the Unistrut. Get a new blade and it is actually pretty easy and will last for many cuts. It is just normal steel in the Unistrut and hacksaw blades are hardened to cut right through that kind of steel. If you need to make a lot of cuts, it would be worth getting a cut off blade - otherwise you will have no problem with an ordinary hacksaw.


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## unkyjoe-sa

What is the hold strength for a 2x3 joist. I am planning on doing the unistrut into my ceiling joists but they are only 2x3 dimensional lumber for the ceiling joists. What is the weight limit on these? I will use three unistruts across three different joists. Also what is the edge holding strength on a 2x3. I also have the option of using lbrackets in the side of the joist if I need to.


Any-ones expertise in this matter is appreciated.


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## RNO

I do not know the strength of a 2x3 but that seems like a very small ceiling joist. I was concerned about the strength of my ceiling (24â€ centers) so I sandwiched 4 joist between two sets of Unistrut.


I used two 6.5â€™ strips on the ceiling running perpendicular to the joist and two parallel strips in the attic above the joists. The ceiling Unistrut is attached with lag bolts to the joists and then I ran two lengths of threaded rod through each Unistrut (between the joists) to bolt to the parallel set in the attic space. This gave me a very stable mount and a stronger ceiling. 


Good luck and I think it's always better to error on the side of caution.


Richard


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## adarsh

I am in process of ceiling mounting my barco graphics 1200.

How are you attaching the unistrut to the projector? I saw the barco mount it actullly sits inside the metal brakets/sleves. First I thought I would just bolt the brakets to the unistrut.


Any ideas about how to lift the projector to the ceiling. I don't think I can get the genie-lift inside the basement. I guy at the Home Depot suggested coming up with some kind of pulley system to lift projector.


Thanks in advance

Adarsh


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## DoyleS

The Genie lifts are only 7 feet tall and fit through a standard doorway. I think you could easily get one downstairs into a basement. A pulley system would be precarious at best. I tried to post some pics but somehow they must be in the wrong format. I'll try again later.


..Doyle


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## wolf

unkyjoe-sa, are your joists really 2x3? That's a very odd size for a ceiling joist. Perhaps you really mean that you have an engineered wood joist consisting of two 2x3's connected with a strip of laminated plywood? If you have one of these modern "I-beam" type joists, then I don't know what to advise you. The proper attachment could vary substantially with the type of engineered beam you have.


-Michael


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## unkyjoe-sa

Yes, it is a mobile home... I was told this by the company that built the home, they are supposed to have an engineer contact me regarding the best way to mount this baby.


But I do appreciate the follow-up.


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## stefuel

A mobile home with 2x3 ceiling joist, Hmmm. Most mobile homes are delivered without the top on and in halves. the top is constructed with pre-formed trusses and installed 24" on center. Each truss due to it's geometry is quite strong. It relys on tensil strength of the wood vs the ridgidity of the wood. Never cut a truss. The ceiling joist in your case does the same job as the collar tie in stick construction. If you remove it the roof would collapse. You need to attach to the part of the truss that is designed to support the most weight, the rafter portion of the truss. You need a good carpenter who is familier with this type of construction and you will be fine.


Chip S.


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## scott jensen

I just flipped my Barco 808 over to measure the distance between the holes in the support legs. I then noticed that the holes are smaller than the threaded rod i bought. I am wondering if I should get smaller diameter rod (it's 1/2") or drill the holes in the projector larger (I think they are 3/8").


Scott


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## scott jensen

I have studied and applied the knowledge I gained from the "Unistrut" Post below. So.....I flipped my Barco 808 over to measure the distance between the holes in the support legs. I then noticed that the holes are smaller than the threaded rod i bought. I am wondering if I should get smaller diameter rod (it's 1/2") or drill the holes in the projector larger (I think they are 3/8").


Scott


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## pjenkins

I'm working through my installation tonight and am trying to reuse my existing screen that I had set up for my Sony LCD projector. I plan on taking the 133" 16:9 screen down to 110" 16:9 for the CRT by masking the sides and bottom of the screen with black felt. The screen is already mounted on the wall and has a top viewing height that my wife and kids like. And therein, lies the problem!


The ceilings in my theater are sloped, going from 8 ft to 10 ft gradually from about 80% out, in other words, like this

Code:


Code:


______
/        \\

So the ceiling height in the center where the projector will go is at 10'


The top of the 16:9 screen is 26.75" from the ceiling. Using the calculations in the setup program/manual, it lists the distance from the ceiling to the center of the screen at 39.75". Given my 1/2 screen height will be 27", you can see where I have a problem! 27+26.75 sure doesn't equal 39.75. So, I have to either

(a) drop the projector 53.75-39.75 = 14 inches from the ceiling or

(b) angle the projector


I believe that (b) is just flat wrong, so I've thrown that option out. Now, how to lower the projector 14" from the ceiling and not have it looked like a complete fool installed it??


Has anyone encountered/solved this? How?


My first thought is the Unistrut, hence the posting in this thread. One thought is to just get 4 >14" bolts to attach to the projector and allow it to hang 14" below the ceiling on the 4 bolts. Talking to my father, who knows much more about bolts than I do, 4 correctly sized bolts, properly anchored into the joists above somehow, should be more than enough to hold the 150lb projector.


My second thought is to build a platform off the ceiling. That would have the added benefit of being close to a hushbox, as I could wall in the back and sides, and keep it looking better by painting the platform/surrounding wood.


Opinions/options welcomed!


Thanks,

Paul


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## BGPGuy

I love this post! Thank you! I would only add that the third piece of unistrut when running parallel with joists limits your ability to raise/lower projector. Running them parallel should strengthen the joist though, right? My pj will be perpendicular to joists and I will place 2 top unistrut pieces to span multiple joists in order to keep the vertical adjustment. Different pj down the road may be lower/higher then current 8000 and I want to make sure I am not projecting on my ceiling mounted center channel shelf (although that may be damn near impossible). The extra 8(?) inches of mounting hardware + height to lenses from bottom of pj may get me past that.


Still is nice to be able to center your picture vertical with unistrut mount rather then try to adjust screen and finished proscenium to the pj.


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## kal

Quote:

_Originally posted by BGPGuy_
*I love this post! Thank you! I would only add that the third piece of unistrut when running parallel with joists limits your ability to raise/lower projector.*
You mean the middle piece? Because the if you raised the projector far enough the bolts would hit the projector itself?


True, but don't forget that while this setup is used by many because it's cheap and flexible, you should still be getting your install correct to within an inch or so. Then use the flexibility of the Unistrut to move the projector in all 6 directions by an inch or two at the most until it's bang-on. This setup is not meant to be able to allow you to raise/lower the unit by 4-5", or to serve you for 2-3 projectors with different height requirements and throw distances.


If you change your projector, spend the $5 for new bolts! 


Kal


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## Patrick C

Not to bump an old thread, but....


I'm getting to the later stages of my HT and am thinking about hanging the PJ (ECP 4000). My thought about the thread is:


can't I bolt the Unistrut onto the projector upside down and gain some ceiling clearance? In other words, I plan on running 2 pieces of unistrut to the ceiling perpedicular to the joists (spanning 3 joists). I would then mount 2 pieces of strut upside down on the bottom of the projector I'd use 4 pieces of 3/8" rod with strut hangers on each end to connect it all (of course I'd have nuts and washers so I could lock it all into place once I finally got it together.


Any reason this won't work???


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## draganm

Chip, the L brackets sound like a safe precaution in an older house with solid wood rafters or joists, but what about the new "fabricated joists" that are a thin flimsy layer of vertical wafer board sandwiched between a 1.5" top and bottom layer of resin bonded ply-wood. you certainly wouldn't want to go through the thin center, and the top and bottom aren't really thick enough for side drilling? As a matter of fact drilling on end dosen't sound too smart either, any ideas?


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## swechsler

How about using bolts with T-nuts (or even better, conventional nuts and fender washers, if you can have someone hold the wrench for you up in the attic)? Drill through the end pieces midway between the center piece and the edge. I'd do one on each side of the waferboard to avoid overstressing one edge of the joist. If you need to run parallel to the joists you may prefer to hang a 2x4 from the joists using that method, then attach the unistrut to that.


An even more reliable solution might be to use very long bolts or threaded rod, and drill through the bottom and the top flange of the joists, using two sets of nuts to distribute the load between top and bottom. I've never worked with fabricated joists, but I'm guessing that they're designed to hold more weight from the top rather than the bottom.


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## chrispy

Patrick, that sounds pretty similar to how I mounted my BG 808s . Check it out!


- Chris


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## SteveGrimm

I posted a bunch of pictures of my Unistrut setup in progress, for those who're interested. It shows things at each step along the way rather than just the finished product. Haven't hung the projector yet (though I've dangled myself from the Unistrut to load test it!) but I'll post pictures of that process as well.


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## CZ Eddie

Quote:

_Originally posted by SteveGrimm_
*I posted a bunch of pictures of my Unistrut setup in progress, for those who're interested. It shows things at each step along the way rather than just the finished product. Haven't hung the projector yet (though I've dangled myself from the Unistrut to load test it!) but I'll post pictures of that process as well.*
EXCELLENT PICTURES! I had decided to go the chain route, but have decided on the unistruts instead, so I could get added flexibility for just a couple of dollars more.

Your pics are the first I've seen that provide detailed close up to allow me to understand the best way to "erect" this set.


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## stephenbr

I am currently considering installation/mounting options for my G70. The Unistrut appears a possible option however my ceiling is raked with a 17.5 degree slope - has anyone got any suggestions as to whether this problem came be overcome using Unistrut while allowing a non perpendicular angle for the rods supporting a level projector (ie. the inside angle between the rod to the projector and the Unistrut is 72.5 degrees)? I hope this explanation of my problem is clear enough.


Stephen


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## timle

I don't think a non perpendicular angle will work with the unistrut. However it should not be necessary.


Forgive the crudeness of the drawing.


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## stephenbr

Thanks - a clear drawing detailing a solution I didn't think of (and although my rafters run down the slope of the ceiling rather than across as indicated the principle could still apply). I have thought that my other option could be to attach L brackets to the rafters, run threaded rod down (longer at front and shorter at back to account for the slope) from these brackets and attach the Unistrut across them to which to mount the projector.


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