My layout is a single deck with a lighting valance above it. I’m using LED strip lights. What would help the strip LED’s more, painting the underside of the lighting valance white or gluing aluminum foil, shiny side showing?
I use a product similar to this:
I can not verify which of several brands I have but it is handy for passenger car roof interiors, structure ceilings, diesel headlight shielding and, yes, it reflects LED strip lighting very well.
Once it is stuck, it is on for good so plan out your installation and just peel back enough backing to tack it in place before you make it permanent.
Lots less messy than paint and very reflective. But you would probably still want to paint the underside of your upper deck anyway wouldn’t you?
At least that’s what works for me…
Ed
Thanks Ed, I could lay down a strip of that tape on both sides of the LED strip. Do you think it will make a significant difference? The wood I used for the upper valance can with a light white primer coat.
Some time back I had some recessed lighting (kitchen & two baths) updated and the contractor suggested painting the inside of the “boxes” with ceiling white paint. I did just that, and the result was obvious.
For your situation, I would tend to paint vs using foil. I have no major reason for saying that, but there are some minor ones that do - ease of painting, longevity of the painting, no concern of metalic foil around electrical circuitry, and overall appearance.
The foil, at least as long as it is not all crinkled up, is the better reflector. But the white paint is a better diffuser. Since you’d never have the foil perfectly smooth, I think the effect would be one of reflecting many points of light, exaggerating the tendency of a string of LEDs on the tape reels to already do this. You’ll lose more light relfecting oof a white painted surface, but the reflections will also not be as sharp, making the light look more like a continuous source.
I used to have tons of tape like that, for some reason my grandfather used to bring rolls home from work when I was a kid (he was NOT in HVAC work!). I used it everywhere, though it has no real strength. Mostly for things liek holding down aluminum foil, since it slosely matched in color - I made a robot costume with lights, a Star Trek transporter console, bunch of things. One thing with tape like that, eventually the adhesive dries out and it starts coming loose. So as Mobileman said, for longevity reasons as well as the reflective qualities, go with the white paint.
–Randy
I worked in a model shop in New York back in the 1970-1980 period and we always used white for our reflective surfaces on flourescent light fixtures as it was more reflective than the polished chrome/ss ones. I always use white now when I want a good reflective background for LED’s. The alum foil will still work but I would take the white over the foil on my layout.
BTW, I have used the foil you show and it does stick quite well and is reflective, but it assumes the finish qualities of the surface it is mounted to (very thin). I tried it on the sides of my Santa Fe F7 to simulate the ss surfaces and it works quite well.
-Bob
As a scientist I have to first point out that neither white paint or aluminum can amplify light, that would require adding energy into the mix to amplify it. Amplification basically means to “increase, or make more intense”.
Randy rightly specified that foil would make the best “reflector” because it is behaving more like a mirror and most of the spectrum from the light source would be bounced or reflected back to the scenes of interest. The problem with foil it is is an imperfect reflector and the more deformed or crinkled is, the more it will be bouncing the light at many angles, and you won’t get it reflected in the direction you need it, and because of that, you loose some of the light away from where you want it.
White paint tends to reflect light better than other colors because it basically reflects all of the spectrum it bounces off of more other colors, which absorb some of the spectrum and only reflect some of it, depending on the color. Therefore, it is a good reflector vs. colors which do not reflect most of the spectrum; this is why we paint rooms white if we want them to be “brighter” vs. other colors. Still, it is second to something that reflects all of the light and energy but as mentioned above, that is not the only consideration. You also want a diffuse pattern to your light so that it is distributted more evenly on the scene.
I am considering getting some 4’ fluorescent style LED light bulbs, which come in clear and frosted. The clear version would probably provide a bit more in raw light or lumens, but I personally prefer the frosted because it diffuses the light, and it is less attention getting than the many points of light versions. I’ve noticed this in Mikes Rio Grande narrow gauge layout when he posts photo’s where you can see above - the many points of light effect is distracting to me, so I think I will prefer something which diffuses the light.
Thanks for the information, very interesting.
Keep in mind that if you have the LEDs oriented right, they produce a very directional light. Any reflection from behind the lamp(s) is incidental and reflected already. The advice to simply paint everything white is probably going to gain more than foil would, because it tends to reflect light arriving from a variety of angles. To best use foil, it needs to be flat, as Randy, Jim, and others advised, but that assumes it’s bouncing light that generally arrives from one direction. You lose that advanatge when the light has already been reflected once and is scattering. White benchwork would tend to deal with that better.
Mylar would increase the brightness the most. Electricians use Mylar to reflect light instead of aluminum foil. Another choice is reflective white paint, specially formulated to be bright. The difference is paint will diffuse the light source removing hot spots, however it is not as bright and can be a big mess.
If you saw the underside of the deck above on my layout, you’d realize how hopeless I’d be if I tried Mylar.[:o)]
The thing about white paint is that once dry, it’s forever outta the way. You can work around it or add stuff without any issues. Foil and Mylar both share the characteristic of being in the way of virtually anything, not to mention the hassle of figuring out how to support them to actually gain the best use.
My assessment is that, assuming there is some slight reflective advantage with foil or mylar, it is more than offset by all their negatives versus the ease of slapping paint on to dry and being done with it.
One thing I’ve found helpful on lower decks is aluminum duct tape, the kind that has the peel off backing leaving aluminum foil with adhesive on one side. I have flourescents down there right now. From certain angles their light would spill in your face. I peeled back enough of the AL tape to stick and made little hoods or visors for ones like that. It’s flexible and can be pushed out of the way as needed, then you can straighten when done.
Using white paint that is used for movie screens would work great.
So there’s a special reflective white paint?
High reflective white paint:
Take Care! [:D]
Frank
Good learnings on this thread for sure!
I’m reminded of the opposite scenario where as “no light” is desired - most typically on the open ceilings of bars and restaurants where everything is painted flat black.
Projector screen paint:
http://www.amazon.com/Projector-Screen-Paint-Definition-Ultra/dp/B00DR7E7Z2
Well, maybe, if price is no object. I’m reminded of the Drive By Trucker’s line that goes something like “don’t get caught with a bucket of rich man’s paint…”[:P]
I’m sure it’s better stuff than the $15/gallon stuff at the big box. However, I’d almost bet in the cheap seats you’d get 90% of the effect the $95/gallon stuff gives you and then you could put the $80 saved against your next loco.
What someone ought to do is repackage that expensive stuff for MRR use. I can think of several uses for it on a much smaller – and more affordable – scale. Painting road markings, a drive-in theater screen, road signs, certain conspicuity markings, etc.
For painting unseen benchwork, I personally would go with the cheap stuff. YMMV
I’ve been an electrician for 40 years and I don’t. There may, indeed, be other electricians that do. So I would recommend preceding the word “electricans” with a modifier like “some” or “a few” or even “many”. This, of course, after doing a proper statistical sampling of the class.
For most of the work I do, I install the light fixtures exactly as specified by the manufacturer, customer, designer and/or the general contractor. And, let’s not forget the opinion(s) of the electrical inspector. That way, I don’t have to hear how “my” method was inadequate/improper. If the person writing the check were ever to specify Mylar, I’d likely put it in. I am VERY interested in and responsive to the person who writes the checks.
I am NOT a lighting designer. I am an electrician. Electrical contractor, actually.
On those rare occasions when I offer an opinion (at home, for one), I recommend flat white titanium dioxide paint as a reflective surface. I’ll note that aluminum foil is conductive, if that is or will become a concern to you.
Ed
Reflective paint (and I think that would likely include projector screen paint) is designed to reflect the light back from whence it came.
So the bright lad who uses it will be reflecting light back to the light source. Is that REALLY what you want?
Ed
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