IN CONTROL

Lighting and Control Panels in ModelsBob Schneider – Whirlpool Corporation

• Most of the displays I do are backlit or try to simulate production control panels. • Because of typical fast approaching deadlines I have tried to simplify the

components needed to accomplish a variety of looks. • Keeping a supply of light parts and powers supplies handy takes away one less

thing to worry about.• I try to use simpler plug and play items so I don’t have to worry too much about

amps, resistors and volts. I dropped out of electronics circuits class but I do like to solder though. More elegant.

• I have had to repair some models from our vendors in the field that were black box kind of affairs. Open it up and there is a rats nest of wires, bad connections, or shorts. Sure it looked great on the outside, but if it won’t turn on in San Antonio Texas, I get to fly down and fix it. And it was glued together. And it was headed to San Diego in a day

• Always leave a way in to fix this stuff because it will go wrong.

OF WHAT?

PLANNING

FIND OUT EARLY IN THE PLANNING STAGES:• What will be on the display• What text or graphic will be backlit• Where will the graphics be, front (A) or back (B) surface or both• Overlay, in-mold decorated (IMD), underlay, dead-fronted• Slideshow, video or special features using a LCD screen, smart-phone, TV• Back lighting, colors, filters, half-mirrored or RGB LEDS• Access needed for wiring, connectors, switches!• How will it be attached• Power requirements• Travel requirements (high or low temps, g forces, gorillas)

4500K to 5600K range for Neutral or Natural LEDs as specified by some manufacturers.

Cool Blue LEDs are 7500K to 9900K.

COLOR TEMPERATURE

MATERIALSACRYLIC: • Sheet stock- go for quality: impurities, crazing from solvents and paints can be an issue with cheaper

grades. Less than 3/16” may warp or sag• Tinted: some grays or bronzes may look murky in thicker pieces. Shine a flashlight through it to check.

Again, select quality, higher $ material.• Milled or thermo-formed shapes: keep it cool when machining and polishing to minimize crazing. Cold air

and water help. Keep solvents to a minimum. Allow time for evaporation or flash-off of paints. • Evonik/Acrylite makes acrylic specifically for the sign industry and back lit signs. I use the LED type for

diffusing. About 25% better than white acrylic.http://www.acrylite-shop.com/US/us/us/sheet/acrylite-led-3rb9eum8heh.html

PLASTIC OVERLAYS:• Thinner Mylar or other plastics need a backer or nest to support it• Limit 2-sided tape to perimeter if possible for easier removal later. Thin (1/8” to ½”) strips work better• Clear layers should be separated by about 0.012” (0.3mm) to prevent contact and sticking that may

show a moiré like effect• We typically have our vendors make these for usGLASS:• Thickness• Color, low-iron (water clear) or soda-lime glass (green tint) • Surface prep and hardness of whatever coating is key. Etch with a cream.• Silkscreen or mask and paint

LIGHT TYPESCCFL: COLD CATHODE FLUORESCENTS LIGHTSAn 1/8” diameter glass fluorescent light tube more often used to light up computer

screens, just like LEDs. Re-purposed by gamers to light up their computer hardware and sold by companies that appeal to gaming industry. They have been re-packaged into a ½” acrylic tube/diffuser to protect the thin high-voltage wire running from end-to-end. They typically piggyback into a 12V computer wire harness

CCFLs provide a nice neon-like glow in white and other colors. Limited by pre-made lengths 4”, 6” 8” 12”. You can use the CCFL tube by itself to get light into some tight spaces. Just remember to insulate the wire.

This web site is who I use for most of my CCFL lighting needs. http://www.coolerguys.com/4inccfl.html

LIGHT TYPES• LEDs (LIGHT EMITTING DIODES)1. Select a voltage level: 9 volts can use a 9V battery. Better selection of products with 12V

because it’s a common car voltage (?) 24V used more in architectural lighting.2. Color: Generally we use “neutral” or “natural” white and tint as needed. Earlier we used

cooler LEDs because that’s what the customers were used to seeing in the marketplace, because that’s what was available and affordable for manufacturing.

3. LEDs produce a narrower range of light color than most lights. Higher quality ones are more consistent, batch to batch.

4. 3528SMD (3.5mmx2.8mm) normal size, 5050SMD larger and brighter. Both available on 8mm wide PC board and self sticking flexible tape (my favorite)

5. http://www.superbrightleds.com/ Has been my go to source although there are many suppliers out there.

5050SMD 3528SMD

LIGHT TYPES• ELECTROLUMINESCENT PANELS AND WIRE: I haven’t had recent experience

with EL lighting. Had problems with shorts and the noise or hum. I expect they have improved in 15 years. Hopefully someone in the audience would like to share their experiences?

• NEON: Yes, neon. Hard to get now but still a great source of intense light that stands up to daylight. Use it to create background glow. Still an option.

• Fiber Optic: Uses a bright LED to pump light through clear plastic fibers. Side-emitting fiber diffuses the light outward as opposed to the end like most fiber optics. Not as bright as neon

FILMS-TINTSWe use tinted films to match LCD number displays or when certain graphics

are called out as a different color than the rest, like cycle-dependent items on a washer panel. Besides the suppliers below, it is possible to spray tinted clear-coat onto a plastic substrate and use that as a filter. Handy when you are matching the tint across several items.

• Roscolux films: filters and equipment available from this theatrical supply company, including LED panels and diffusers http://www.rosco.comn

• 3M Automotive and Architectural window films: Mostly greys and ambers, mirrored films. http://solutions.3m.com/wps/portal/3M/en_US/Window_Film/Solutions/

• Solar Graphics films: architectural film supplier with full spectrum of colors. Nice samples. http://www.solargraphicshome.com/

TECHNIQUESBACK LIGHTING1. Diffused light shining through clear graphics (dropped out) surrounded by

opaque field2. Set lights 1” back to help spread it out, minimize hot spots3. Use white material when creating the light box that surrounds the source. Or

paint it white. Diffuses the light better. Chrome or polished metal may create a hot spot or shadow

EDGE LIT: 4. Like on an LCD computer screen, fluorescent tubes or LEDs on the edges light up

the entire panel with an even glow5. Requires a white back surface, several diffuser layers, and image layer. Dust

specks between layers may cause moiré effect6. Harder to set up on the fly but gives a low profile-high quality image

PROJECTED: 7. Using a small presentation projector to show an image on a back projection

screen8. Images must be flipped to read right from the front9. Heat from the light-source should be vented

TECHNIQUESBACK SPRAYING1. Spraying a solid opaque paint layer onto the back surface of a clear or tinted

material2. Graphic elements (words, arrows, dots) may be silkscreened, engraved, or use

rub-downs as a mask that will be removed with solvents, sanding or by picking them out

3. Front surface can be left clear or also receive more paint detail

IN-MOLD-DECORATED OR BURIED GRAPHIC INSERT: 4. Like a overlay but inserted into the injection mold when the production part is

made5. We simulate this by spraying the front surface with the graphic with 2-4 coats of

catalyzed clear until the graphics recesses are filled in. Usually polished in between each coat to 600 grit until the final one is polished

DEAD-FRONTED:6. Looks like a solid surface on the A surface until the lights are turned on behind it7. We spray a light coat of paint just enough to cover but still transparent to let the

graphics shine through8. Or the background color is close enough to the material tint that it seems like the

graphics are just a shadow.

CONSTRUCTION• Design for disassembly, access, repairs• Back loaded displays with screw mounting as opposed to floating displays with the

panel stuck in place with 2-sided tape. Front loaded into a recess is 2nd best option• 2-sided tape is attached to whatever is on the surface. Paint peels off of acrylic and

glass unless it is bonded or the surface abraded somehow. A layer of vinyl on the B side will also eventually give way

• Try to use a hidden ledge or some physical fastener to at least support the piece vertically. Gravity is not our friend

• Remember to create space and access for all the connectors, power switches, USB and charger cables when working with smart-phones or LCD displays

• Always have a back-up unit ready to swap in before show time• Work with the actual image when positioning whatever digital display screen you

are using. Suggest using a smaller image than full-screen so it can be adjusted to fit the target viewing area

• Place the display as close as possible to the “A” surface to reduce parallax effect• View the final construction in a low light condition to pinpoint light leaks or bleed

thru

CONSTRUCTIONWhen working with LEDs and wiring in general you

might need:1. A good soldering iron with a fine tip. Temperature controlled is

best.2. 60-40 blend of solder(more lead)3. Fine wire cutters and wire strippers. Sharp teeth work, too4. Plastic terminal blocks work well to keep the clutter down.

McMaster-Carr has some good ones.5. If you want to go solderless most of the companies that sell LEDs

also sell connectors that clamp onto the LED strips, and plug type connectors to the power supply

6. Good eyes because these things keep getting smaller.7. Stick to low voltage for safety. 120 volts is unnecessary.8. We use standard 6 plug power strips to plug all the power supplies

into. Power strips are fastened in place and the cord zip - tied as a strain relef.

PRODUCTION EXAMPLES