AVS Forum banner
Status
Not open for further replies.
1 - 12 of 12 Posts

·
Registered
Joined
·
357 Posts
Discussion Starter · #1 ·
Well, this is one time, I think, that a small theater is a benefit.


I'd like to do a fiber optic star ceiling with a drywall ceiling. I can't get access from the floor above. However, since the largest star field I am considering is 6' x 10', I think I may be in luck. I have 16" of space above the ceiling (truss space between floors). I have long arms, and from a ladder, I can reach across 3' of sheetrock after it is installed on the ceiling. So, my plan is to install the sheetrock from the center out. In other words, hang the sheetrock for the star field portion of the ceiling (happens to be in the center of room) first. Then, install fiber optics by reaching in from the periphery of the installed portion. Then, after fiber is in place, hang the rest of the rock.


So far, so good. I think.


But, how to handle the trusses (joists)? Since I plan to model an actual sky map, truss locations just may cover a point where a star should go. Especially for a particularly area in the ceiling where 4 trusses are used together (fastened together side-by-side), functioning as a single truss 6" wide.


My proposed solution is to fir out the trusses. Except, I'll omit small pieces the firring where stars need to go. So, the optical fiber will be running along the top of the sheetrock, and then "turn the corner" into the sheetrock in the space that exists between the bottom of the truss and the sheetrock. (The space will be there because of the firring strips.)


Hence, the question: How thick do I need to make my firring strips so the optical fibers can turn the corner without damage? I suppose that depends on the thickness of the fiber. The maximum diameter fiber I plan to use is 1 mm.


Might anyone who has installed a fiber optic star ceiling have any thoughts on minimum turning radius for optical fibers?


Thank you.


DG
 

·
Registered
Joined
·
268 Posts
The problem I foresee in your plan is that you definitely do not want to paint the background let alone finish the drywall with the strands installed. The problems you mention among others are why most are installed in drop ceilings. If you are after a more monolithic look over the tiles consider a drywall ceiling with the center set up as a mock skylight or series of skylights. Black panels (that represent the glass) would hold the fiber optics.
 

·
Registered
Joined
·
3,639 Posts
Oooo, good point Wayne. That would be a real pain trying to tape and bed a drywall ceiling with fiber optics hanging out all over. Plus what if he got through and found that one of his fibers broke during installation. Can't replace it.
 

·
Registered
Joined
·
5,896 Posts
I have been curious about this for a while, but didn't want to start a new thread... hence, I'll tag onto this one. ;)


What fiber optics do people commonly use for starfield ceilings? Can you buy the "strands" in bulk/rolls, or do you have to get pre-terminated lengths? Does everyone get a ready-to-go 'kit' complete with lamp, lamp box, fiber strands, etc., or can you just buy the fibers and make your own lamp box?


I've seen a few posts where people used "commercial" kits ready to install. Any DIY-type options?
 

·
Registered
Joined
·
594 Posts
This place http://www.thefiberopticstore.com/ sells the kits at a decent price. I bought a combo pack and 10' of the 64 strand cable to make a 4x8 star panel. There are one or two pics on my web page (see sig). The panel was VERY easy to make and is much easier than working with drywall. Basically you poke holes through a painted piece of rigid insulation and then thread the optics through. The perimeter is cased with trim. The light source is a fluorescent tube mounted in the rafters above.....
 

·
Registered
Joined
·
357 Posts
Discussion Starter · #6 ·
I think painting can be handled in two ways. In both cases, taping and mudding are done first. 1) Paint before installing optical fibers. (This is what I was planning). 2) Spray paint after fibers are installed. (This is also how one could change colors later.)


Maybe a "skylight" panel would work. But, I'd also be concerned that the extra absorption might affect the acoustic design. Guess I'd have to ask my consultant about that.


Fibers can be bought as cables or bulk rolls of individual strands. I think it's common to buy an illuminator, but some folks have successfully made their own (for relatively small number of fibers) out of large, very bright LEDs.


DG
 

·
Registered
Joined
·
268 Posts
Perhaps I am not getting it but with a 6 x 10 starfield you will be involving at minimum 3 sheets of drywall. I just dont set how you can reach from the perimeter if you are taping and muding and painting before installing the strand. Also you will more than likely have more than a hundred light points in that area and that would be tough to deal with painting after. The strands are suppose to protrude a minor amount. Anyway let us know how you make out.
 

·
Registered
Joined
·
357 Posts
Discussion Starter · #8 ·
I think I can tape and mud from underneath, just like normal.


I know I can reach in 3' from each side, so I can handle the whole area.


Probably paint first, but, if I paint after installing fibers, I just cut off the ends after I paint.


I'm really liking the idea of a separate "skylight" panel made out of polystyrene or similar.


If I do stay with sheetrock, I'm now also thinking I can drill slanted holes right through the joists and sheetrock (then use mud to change the angle of fiber hole exit to more nearly perpendicular). That way I might avoid firring strips. But, if I do use the firring strips, then I'm back to the original question of how tight I can do a 90 degree turn.


DG
 

·
Registered
Joined
·
268 Posts
The radius question is a very good one. I would be interested in the answer as well. Also your idea to trim after paint might well work. I did not think of that. Strands that cannot run exactly 90 degrees through the surface would not be a problem. A level trim on a strand that is angled through will simply give a larger diameter light point which is interesting to have in the field anyway.
 

·
Registered
Joined
·
440 Posts
I used 1mm fiber on my ceiling. I have a part reel of material left over, cut a small piece, and bent it in a circle that did not appear to stress it in any way. The circle was ~ 1" in diameter, so I assume you would have no problem.


BTW, the supplier of my star ceiling materials provided a hot wire method of cutting the fiber. This makes a round "blob" of plastic on the end which serves two functions: the stars are larger and brighter, and the fiber can't be pulled back through their holes.
 

·
Registered
Joined
·
1,237 Posts
the rule of thumb for any fiber is more then a quarter is too much.. this from someone who does fiber testing for communications ;-)
 

·
Registered
Joined
·
1,011 Posts
The bend radius can be fairly tight since the quality of light transmission does not need to meet the spec's of those used for data transmission.


I would however not build any system that prevented easy access to the space. Anything can and usually will go wrong so I personally would not drywall the ceiling.
 
1 - 12 of 12 Posts
Status
Not open for further replies.
Top