Introduction: LED Strip Spiral Dome - 10 RGB Channels
A project demonstrating a technique of twisting a loop of perforated metal strapping(pipe hanger) and applying LED strip to them. Fairly simple, project that utilizes a surplus/reuse 20" diameter diffused hemi-sphere, probably made of HDPE, some 12 volt RGB LED strip, perforated metal strapping, MDF base board, and a NLED 30 Channel High Current LED Controller. The controller is a bit overkill for a project such as this, as it can handle many times more 12 volt LED strip than what is used here, but in the spirit of reusing, the particular controller used was an early prototype and otherwise would have been scrapped. Alternatively (addressable) LED pixel strip and a compatible controller, such as a NLED Pixel Controller Ion, could have been used.
Step 1: Supplies and Tools
- NLED 30 Channel High Current Controller or NLED Quasar
- 4 Conductor 22AWG Ribbon Cable
- 12 Volt RGB LED Strip, Choice of 30, 60 or 90 LEDs per Meter
- 12 Volt Power Supply, proper amp rating
- DC Power Jack, Panel Mount, Optional to have included with purchased Power Supplies
- Data Jacks - Male 3-pin XLR, Female 3-pin XLR, other options are 5-pin XLR , RJ-45, or whatever they want
- White plastic dome, this one is from a street light of some type. Surplus and Reuse stores are good source.
- 5/8" thick MDF large enough to cut the base plate for the plastic dome
- Black Paint
- Metal Strapping, with perforated holes, pipe hanger
- 2x2 board, about as tall as the plastic dome, in this case it was 14"
- Pan head screws, short
- Solder Iron and Solder
- Diagonal Cutters
- Hot Glue Gun
- Misc Screw Drivers
- Router with Rabbit bit
- Jigsaw/Bandsaw/Any saw that could be used to cut a circle out of the MDF
- Power Drill
- 1/2" drill bit
Step 2: Base Plate
Base Plate: Made of 5/8" MDF, it holds the plastic dome and supports the metal strapping.
- Cut 20" diameter MDF disc.
- Routed a rabbet(notched corner) on the outside edge on one side, measured the inside diameter of the dome to figure the depth.
- Found and marked the center(Thales Theorem), using the center mark and a protractor, divided the circle into 10 parts.
- Marked approx 1" from the edge on the division lines.
- Drilled a 3/8" hole on either side of the division lines, so they over lapped, making an approx 3/4" x 3/8" wide hole.
- Drew out the shape for the data and LED display panel, and cut it out with a jig saw.
- Rubbed watered down wood glue into the exposed edges of the MDF to reinforce it, re applied after it dried. This glues the particles on the edge together, making it stronger and less likely to chip.
- Painted all surfaces black after the center column was installed.
Step 3: Center Column and Metal Strapping
- Cut a 9" long(for a 20" hemi sphere) pine 2x2.
- Securely attach to the center of the base plate(already marked) glued and screwed.
- Then paint the base plate and center column black.
Metal Strapping Loops: Part that makes the project, the interesting twisting effect.
- Test fit the metal strapping to find the length it should be, did some trial and error to find the best. As in the diagram there has to be extra strapping, so once it gets twisted it will be parallel to the dome. Since the aim is to have the LEDs a consistent distance away from the dome.
- Place a temporary nail in the center of the center column and line up the perforated holes with it.
- Cut the metal strapping to length, and place each end through opposite holes on the base plate. Screw them in with pan head screws.
- Repeat for all 5 pieces of metal strapping.
Twisting: Requires a really simple jig(pictured) The nails fit into the perforated holes of all the metal strapping loops at once, and then is twisted to get the desired effect.
- Grab a piece of scrap, drill a large hole in the middle, 1" or so.
- Use some scrap metal strapping or reference the installed pieces and mark the jig for where the nails should go
- Install the 10 nails on the jig.
- Attach the jig to the strapping loops, line up the nails into the perforated holes.
- Remove the temporary nail holding the loops.
- Twist the jig, which will twist the metal strapping into shape.
- Through the hole in the jig, use a wood screw to screw down the metal strapping loops. Wrench it hard in so it will hold them steady.
- Tweak the positioning and check that all the loops are even looking.
- Remove the jig and add more screws through the metal strapping perforations.
Step 4: LEDs and Electronics
Mount The Controller and Connectors:
Test fit where the power, data connectors and external LED display will go.
- Position and mount the controller with stand offs or screws.
- Mount the power, data, and external LED display.
- Connect the data and power connectors to the controller.
- Measure and cut the LED strip to length, 10 strips.
- Number them and test fit them, measure the distance to the controller position.
- Cut 4-strand wire to length, strip and solder to the LED strip.
- Repeat for all strips.
- Clean off any oils from the metal strapping with isopropyl or similar.
- Remove adhesive backing and apply to the metal strapping.
- Apply, and rub the LED strip on well. Make sure to place them in the correct order.
- Connect the LED strip wires to the controller, again make sure in the correct order.
Power Up Test:
- FIRST check everything, check every connection, ensure power polarity is correct. Look for any frayed or loose wires and fix it.
- Once everything is checked, apply power, the device should turn on and all LEDs should starting working.
- Look closely at the LEDs and see if any are missing colors(unconnected) or if the colors are wrong(wired out of order)
Secure and Route Wires: With everything tested the wires need to be routed and secured.
- Route the wires nicely and secure them, used here were carpet staples.
- Some foam was forced into the holes in the base plate to secure the LED strip wire connections from shaking or coming loose.
Step 5: Software
Close It Up: The plastic dome is pressure fit onto the base plate then secured with screws from the backside.
Software: Most NLED Controllers are compatible with the NLED Aurora Control Software. The software is used to create a multitude of patterns and sequences on a computer then, upload them to the compatible controller for the device to run by itself, without a computer connection. The simple GUI makes it easy for anyone to create custom color sequences of any sort and upload them to the controller over the USB connection. Great for any LED project that requires custom color sequences. In addition to standalone sequences, it also supports USB Live Control, send packets over USB to the device for direct control of the outputs. It supports single color, RGB, or RGB+W/U.V. LED configurations.
Controllers come loaded with many sequences, so software usage is optional. The software is freely available and requires a USB cable to interface with controllers.
Step 6: Completed
Thanks for Reading, please Contact with any questions or comments. Visit our Profile Page for more Instructables. A full line of LED Controllers for both LED (addressable) pixels and regular LEDs are available for purchase and more types will be added in the future. Most are compatible with the NLED Aurora Control software, great for wearables, infinity mirrors, decorations, stage lighting, art projects, and more.
Please Contact Us with any questions or comments about this or any other project. Northern Lights Electronic Design offers customization of any project or controller for personal or commercial uses. In addition to offering custom design and manufacturing of electronics to a customers specifications. Please Contact Us with any inquiries.