I am working on a project and am looking into different ways to diffuse the light. This is one of those crazy projects that I have to get out and I want the client to have a choice of materials.
The below photo is a graphical rendering of a building with ,what we call, a light spike sticking up out of it. The total height is 30'. We were going to originally use a clear shell to cover the lighting system but have decided it best to try to diffuse it. We are going for a "star wars saber" effect. The colored photos on the left side are the mockup and I placed a 3m #70 diffuser film onto a clear acrylic skin. I also know of a frosted acrylic #3172 material but need a 3/4" thickness to the body.
1. We don't want to sandblast the surface. 2. We really don't like the diffuser film because of long term maintenance issues. 3. The acrylic #3172 only comes 1/4" thickness (that I know of) 4. I have used grip flex but don't think I could control the consistency SO.....
What would you use?...Any thoughts?
Thanks in Advance!
-------------------- Robert Beverly Arlington, Texas Posts: 1023 | From: Arlington, Texas | Registered: Jan 2001
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Without seein the actual light source it is difficult at best to understand what you're up to.
When you say diffusion are you implying you want the light to be even all over instead of the hot spot you have?
If thats the case heres something we used to do with haligen lamps acting as a light source in a huge illuminated can...and I think a revamped version could work for you.
In front of the lamp we would place an aluminum baffle (063 or .090) and perrferate it in an even pattern with large holes to the middle and smaller to the outside.
From that I would surmize an aluminum tube could be used larger holes to the wide area and gradually smaller as you work your way down the cone. (keep the tube closer to the light than the cone).
Seems to me tho since it is conical... a single light source at the base would be more satifactory. Since it doesn't protrude into the cone there sould be no "hot spot"...in fact you could still use a light "baffle" at the base large holes in the center smalller to the outside ...with graduated holes between.
Just a thought!
-------------------- "Werks fer me...it'll werk fer you"
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I just read your post over agian and realized you're not concerned with the light source...rather the material covering the light source.So whats wrong with something like awning material like they used in the Denver airort roof...especially if this thing is going to be 30'tall...you'll need something light weight. flexible and strong.
Not many things diffuse the light like some of these new vinyl awning materials...and they come in seemingly endless rolls.
Ok... I shot all my ideas...let us know what you do.
By the way how tall is this building?
[ April 14, 2003, 09:31 PM: Message edited by: Monte Jumper ]
-------------------- "Werks fer me...it'll werk fer you"
Thanks for the insight...I guess I did leave a few holes in the parameters. The building height is +/- 50' to the spike tip. The spike is 12" in diameter for 23' tapering to 6" for the remaining 7'. We were ask to create a rigid structure that would encapsulate the lighting which is an led array mounted to a 2" aluminum pole inside the encasing.
The exterior skin is what we are deciding on now. The leds are programmable which we decided over just putting neon in it. There are 3 rows in a triangular pattern vertically going up the pole and we would rather try to diffuse what we have without the additional cost of adding more led's but trying to disperse it over the scope of the surface rather than leaving a single line appearance up the pole.
I am not familiar with the awning material but would be interested in it's possible application. Do you think it could be attached to the acrylic skin taunt enough and appear as a solid product?
-------------------- Robert Beverly Arlington, Texas Posts: 1023 | From: Arlington, Texas | Registered: Jan 2001
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I used to design light shows for bands and may have your answer. Locate a stage lighting supply and ask about diffuser gels. They come in sheets of various colors and clear, some are cut to fit the lights, others come in a 2 x 2 sheet that you can cut to whatever you need. They are also pretty heat resistant (they are made to be placed in front of anywhere from 500 to 1000 watt bulbs) so that should take care of any heat issues you may have.
Give it a shot, nothing like using the right thing for the job.
-------------------- Tony Broussard Graphic Details Digital Media Loreauville, LA Posts: 395 | From: Loreauville, LA | Registered: Jul 1999
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I didn't even think about the diffuser films like that...but I have used them in special lighting and am not quite sure how that film can be attached to either the interior or exterior faces of this structure...any thoughts?...
I actually thought about pin mounting or "screwing" the diffused 1/4" acrylic to the exterior face of the acrylic shell but was afraid I may not be able to seal it enough from allowing particles to get inbetween the materials...
I am just trying to anticipate any possibilities
-------------------- Robert Beverly Arlington, Texas Posts: 1023 | From: Arlington, Texas | Registered: Jan 2001
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Why do you not want to sand blast it? If you need a source for the diffusion jell, I work in stagecraft and I know a few dealers.
Good luck
-------------------- Mike Pulskamp Pulskamp Arts Sacramento, CA mpulskamp@earthlink.net Posts: 165 | From: Sacramento, CA | Registered: Dec 2002
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Are the LED's already purchased and installed? Another product that my be interesting for future projects is Super Instant Flexilight: http://www.wideloyal.net/main.html
I have never used it myself, but it seems to have some good properties for a project like this. They state that the average life-span of each bulb is around 35,000 hours.
Is it possible to mount the diffusion gel inside the acrylic shell? Rosco makes a product called Roscobond that can be used to apply the gel to the acrylic. Or, maybe you could try to use some form of spray mount product or a thin coat of epoxy - WEST 105/207 may work. My only concern is the light fastness of the product. Rosco has a lot of tech info on their site. At any rate, I think you will need some sort of UV on the exterior of the spike.
The awning material may be a good option as it is designed to be outdoors for extended periods of time.
How about window tinting gels?
You have any CAD drawings of this beast? Maybe that will help us get a better idea of what you are trying to do. Are you using a clear light source? How is this thing supported?
Keep us posted… and good luck,
Marty
[ April 15, 2003, 09:04 AM: Message edited by: Marty Engel ]
-------------------- Marty Engel Berkley, MI Hill Mountain Signworks LLC
marty@hillmountain.com 248-890-8265 Posts: 58 | From: Berkley, MI | Registered: Dec 2002
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What we have done to get a frosted look, instead of sandblasting, is to spray clear acrylic with a matte clear coating. The matte clear produces a nice soft finish.
-------------------- Jean Shimp Shimp Sign & Design Co. Jacksonville Beach, Fl Posts: 1266 | From: Jacksonville Beach, Fl. USA | Registered: Nov 1998
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The led's run in 12" strips vertically up the internal mounting pole.
I have used the rope light from loyal and it is terrible...I had some lit that lasted less than a year.
as for diffusion: as for the question on sandblasting...you can only get so much frost from doing this and it becomes a dirt magnet!.. It does not provide near enough diffusion of light.
The 3m film is ok...but the client does not want any maintenance issues and I won't guarantee it won't be in need of a reskin in 10 years!
Here is a bit better graphical rendition of the project image
and the only other thing not mentioned is I want to stay away from laminating plastic due to the pain in the butt method of keeping air pockets from forming!
OH...and Monte, the spike is comprised of 3 10' sections. Maintenance will be performed as section will be encased in metal collars and can be removed for light replacement. That is the reason for using led's rated at 135,000 hours. We guestimate that properly done, this unit will need no service for 10 years.
At this point, I am seriously considering a frosted glass with acrylic skin and use a metal trim to hold in place. The whole reason to cast acrylic/mold acrylic was to avoid seams and actually creating round columns would have shot the price up considerably.
Hope this helps!
[ April 16, 2003, 08:24 AM: Message edited by: Robert Beverly ]
-------------------- Robert Beverly Arlington, Texas Posts: 1023 | From: Arlington, Texas | Registered: Jan 2001
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Well? How did you do it? I missed your original post, In Los Angeles there are towers at LAX that kinda does the same thing, though being that they are probably 60 or 80 feet, they had to illuminate it differently, here is the project sheet from the designer (Selbert Perkins Design Collaborative) http://selbertperkins.com/PDF/lax.pdf
Rick
-------------------- Rick Chavez Hemet, CA Posts: 1538 | From: Hemet,CA U.S.A. | Registered: Jun 2001
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We laminated octagonal staves together from 3/4" acrylic with a 3/16" white inner core. The led lighting was mounted inside on a vertical aluminum tree. It was quite a project heaving these 400 plus babies into place inside the tower on scaffolding, but they were in three sections and collared at the point of connection.
It is weird how well the photos pic up the true color of the light until you get a distance from it...then they appear white, but they aren't...as you can see from the glow!
is that the info you were asking?
-------------------- Robert Beverly Arlington, Texas Posts: 1023 | From: Arlington, Texas | Registered: Jan 2001
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Yes that is, I am not a big fan of LEDs, (currently haviing problems with white LEDs on a project-inconsistant color) but your project looks really good. A couple of questions, does the color change at once or slowly, how often, and does it shorten the LED life with it going on and off, and with all those LEDs (I know they are low voltage) is it hard too control your power to them, since they don't do well with power fluctuations. I am very dissappointed in the salesman pitch I got from one vendor, I know white LEDs have thier problems but they forgot to mention the most important to me, but the upsides look very promising. Being that I specify in my drawings, I want it to see what you think of them.
Thanks Rick
-------------------- Rick Chavez Hemet, CA Posts: 1538 | From: Hemet,CA U.S.A. | Registered: Jun 2001
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For future reference, there are ceramic frits that can be applied to materials like plex and glass basically just like the process in screenprinting, which diffuse light.
As for LED's, Lumileds (www.lumileds.com) makes some of the nicest and brightest LED's around. I buy the individual lamps in bulk for building the custom automotive tail light assemblies I've been selling but they sell pre-built units for architectural and signage uses.
-------------------- "If I share all my wisdom I won't have any left for myself."
Mike Pipes stickerpimp.com Lake Havasu, AZ mike@stickerpimp.com Posts: 8746 | From: Lake Havasu, AZ USA | Registered: Jun 2000
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