Introduction: Polychrome LED Filament Lamp

About: Hobbyist wood worker, builder, tinkerer of all things.

I found these clear, filament style, LED bulbs at a hardware store on Castro Street in San Francisco! The bulbs themselves are great and I wanted to make a simple light fixture to show off the whole rainbow.

For this project I used S4S hardwood lumber that you can buy from any big box hardware store such as Home Depot. I decided to use solid walnut for this project. I love the mid century vibe walnut brings and also the rich depth of color this beautiful hardwood takes on after applying a finishing. That said, you can use any hardwood you perfer. (I'd love to make this again with Zebrawood!)

Step 1: Tools + Supplies


• Miter saw - Metabo HPT 12-Inch Compound Miter Saw, Laser Marker System, Double Bevel, 15-Amp Motor, Tall Pivoting Aluminum Fence, 5 Year Warranty (C12FDHS)

• Table Saw - DEWALT DW745 10-Inch Table Saw, 20-Inch Rip Capacity

• Orbital Sander

• Drill Press

• Cordless Drill

• 5/16" Wood Drill Bit

• 3/8" Thread Cutting Tap

• 1-3/8" Forstner Bit

• Drafting Compass

• Speed Square

• Tape Measure

• Ruler

• Phillips Screwdriver

• Wire Cutter/Stripper

• Strap Clamp

• Bar Clamps (I ended up using 5 of clamps varying sizes.)


• 1x Red Feit Clear LED Filament Bulb 4.5W - FEIT Electric A19/TR/LED LED Light Bulb, A19 2.38" D x 4.44" H, Red

• 1x Orange Feit Clear LED Filament Bulb 4.5W - Feit Electric - Orange Filament LED 25W Equivalent Dimmable Clear Glass Light Bulb, A19 (A19/TO/LED)

• 1x Yellow Feit Clear LED Filament Bulb 4.5W - Feit Electric - Yellow Filament LED 25W Equivalent Dimmable Clear Glass Light Bulb, A19 (A19/TY/LED)

• 1x Green Feit Clear LED Filament Bulb 4.5W - Feit Electric A19/TG/LED 25W Equivalent 4.5 Watt Dimmable Green Filament Glass A19 Transparent 4.5W LED, E26 Medium Base, Clear, 2.38" D x 4.44" H

• 1x Blue Feit Clear LED Filament Bulb 4.5W - Feit Electric - Blue Filament LED 25W Equivalent Dimmable Clear Glass Light Bulb, A19 (A19/TB/LED)

• 1x Purple Feit Clear LED Filament Bulb 4.5W - FEIT Electric A19 A19/TP/LED LED Light Bulb, 2.38" D x 4.44" H, Purple

• 9 ft x 0.75" Walnut (or hardwood of your choice) Lumber

• 1 Can Spray Polyurethane

• Wood Glue

• Sandpaper

• 12x 3/4" Pan Head Screws

• 4x 1" Brass Wood Screws

• 6x Light Sockets - Leviton 9063 Medium Base, Pony Cleat Lampholders

• 6 ft 18/3 Round Cloth Covered Electrical Cord

• 1x Antique Electrical Plug

• 4 ft Black 18Ga Wire

• 2 ft White 18Ga Wire

• 2x 2-Terminal Lever Wire Nut

Step 2: The Lamp Base Sides

Let's start off by creating the four sides of the lamp's base box. From your 9' length of wood you'll first need to cut two 22.5" long pieces with a 45° miter on each end. These will be the back and front panels of your lamp base. I cut these on my compound miter saw. first made sure to take some time to dial in the setting for my 45° cuts - you will want to cut a test piece on some scrap wood to check the two cuts met for a perfect 90°

The next step is to cut two 4.5" lengths with a 45° miter on either end, do this at the Compound Miter saw while you have your settings still dialed in.

I then cut the 4 pieces for the sides down to 2-3/4" at the table saw.

We're going to glue these four sides now so that we can measure the top and base to fit later. Lay out the four pieces and check for fit, now apply a thin layer of wood glue to each miter. I used a band clamp to help with this glue up but you can do this with just painters tape if you don't own one. Google "miter joint glue tape method" for tips.

Put the assembled sides somewhere for the glue to dry.

Next we're going to drill a hole in one side of the lamp base for the power cord to exit. I'm going to use a strain relief fitting to help firmly secure the cord. The fitting I used has 3/8" threads. Initially, you will need to drill a 5/16" hole 1-1/2" up from the bottom of the lamp base side that you prefer to have your power cord on. When making the hole, you will want to keep the drill as square to the surface as you can - this is important. Now it's time to thread the hole. Take a 3/8" tap (thread cutting tool) and insert it into the hole. Begin slowly winding the tap. As before, it's again necessary that you keep the tool square to the surface.

Lessons learnt the hard way...

• CONCENTRATE when cutting the miters. Make sure you cut them in the right direction, I suggest you sketch a quick line when measuring to indicate which way each should be cut.

• Check every time you're buying hardwood that it is not bowed. Even the slightest bow in the wood for the sides will cause trouble later.

Step 3: The Lamp Base Bottom + Top

Now it's time to make the top and bottom of the lamp base. To get a perfect fit you'll want to take some time making sure your measurements are precise.

Once the lamp base top and bottom pieces are cut to length (miter saw) and width (table saw) mark the top piece to prepare it for drilling holes for the bulbs. These holes are centered in the width of the board and the spacing between the center of each is 3". With a compass I drew a 1-3/8" circle on each of these 3" marks, using the mark as the center.

Place the 1-3/8" Forstener bit a drill press and proceed to drill the six holes where marked. Remember, go slowly and place some scrap wood underneath the hardwood you are drilling to help prevent tear out.

Once you've finished drilling, gather your clamps and glue etc. Apply a thin layer of wood glue to all four outside edges of the top. Push the top down into the assembled frame and apply as many clamps as you feel you need to hold it in place, applying additional pressure where needed to close up any gaps along the joint. Once you're satisfied with this, put your assembly to one side for a few hours so the glue has a chance to set.

Lessons learnt the hard way...

• If you're working on walnut use a chalk pencil to mark your measurements on your board. This save you from having to hunt for the pencil marks - like I did.

Step 4: Electrical+Wiring

Now that the glue on the top panel and sides is drying, it's time to work on getting power to all the bulbs. This will include installing the lamp holders and wiring them in. You will use the same measurements you marked to drill the top panel, six points centered on the board and every 3 inches, to align the bulb sockets to your cut holes. Once this is done, place one of the six lamp holders you purchased on the center of each your marks. Aligned the screw holes along the center line as seen in the picture above (Visual Reference for Wiring) making sure that you place all of the live terminals (gold screws) on the one side and the neutral terminals (silver screws) on the other side. It does not matter which side you choose, as long as you are consistent with the live vs neutral. Then screw each lamp holders down with 3/4" screws. After the lamp holders are securely affixed to bottom, you will run your live and neutral lines. Take both the black and white 18 gage wire and measure, cut and strip five lengths of each color. These lengths should be 3 1/4 inches long so that you can run from each of the terminals on the lamp holder bottom to the next, on both sides. Go back and add one additional live (white) and one additional neutral (black) wire of on each corresponding side of the first lamp holder. These wires will be used to connect to your power supply cable later. CAUTION: If you're unsure about electrical wiring, consult someone knowledgeable who can safely guide you through the process step by step.

I chose an interesting antique style lamp plug from amazon rather than a plain white one. I connected this to a 7 foot length power supply cable that comes wrapped in decorative gold cloth. This small detail really adds a lot style to the look of the whole lamp.

Now we slide the strain relief fitting onto the cord (but not into the threaded hole yet...) and pull through several cord inches. Trim back enough of the wire to connect to your lamp bases later. For lamp project like this, I use Wago Lever Nuts instead of classic twist on wire nuts. The Lever Nuts hold the wire much firmer and will not slip off by accident.

Time for a bench test! Hook everything up. When you do this be aware that all the bare terminals inside are live. Now, make sure you see all your bulbs light up. If you have any issues or problems immediately unplug the power cord. Trouble shoot what might be wrong by going step by step through all previous instructions here until you again bench test and see all bulbs lit. Keep in mind that safety is always your first and foremost concern.

Now unplug the the power cord and detach the lead wires. We're going to prepare some screw holes for later. We'll be installing the lamp base bottom within the lamp base side frame you constructed with 4x 1" brass screws. Insert the base into the sides and slide it up until the lamp holders are just below the level of the holes in the top piece. Mark where the base is and pre-drill two countersunk holes on each side. We'll use these later on.

Lessons learnt the hard way..

• Make sure to be extra careful that none of the lamp holders move when you are screwing them down.

• Use Pan-head screws to secure the lamp bases - not counter sunk screws, like I did. Not good,

• The antique style plug is truly elegant and beautiful but not the sturdiest way to go. If you foresee the unit you are making to be subject to more travel or need consistent plugging and unplugging, you might consider a regular, run of the mill style plug you can find at your local hardware store.

Step 5: Finishing Touches

Get ready to do some serious sanding. This project will look it's best if you have the patience to "go through the grits" as my husband calls it. Start sanding all exterior wood surfaces with 80 grit sandpaper, then move on to 120, then 220 and finally 400 grit sandpaper to hone a handsome, smooth finish on your hardwood. This will be most easily done, in my opinion, with a random orbit sander. A palm sander, with a bit more elbow grease, will also suffice. If you do not have an electrical sander of ether type you might want to go for old fashion, manual hand sanding - it will take you good bit more time and energy, but could be quite rewarding. Then wipe all surfaces with a damp cloth to remove all dust and any unwanted shavings. Spray on the first coat of Polyurethane on the exterior of the lamp base panels. Let them dry, lightly sanding it with 440 grit sandpaper. Wipe away the dust and then repeat this until you are satisfied with the finish. I sprayed on 6 coats total. Remember, you don't sand the last coat after application..

Now for final assembly. Poke the cord through you threaded hole, then screw in the strain relief connector. Now attach the live and neutral wires from the lamp holders to your braided cord with leaver nuts. Fit the bottom panel into the lamp base. Secure this panel to nearly finished lamp with brass screws through the pre-drilled/countersunk holes from earlier. Now screw in the bulbs in the correct order Red, Orange, Yellow, Green, Blue, Purple.

Lessons learnt the hard way..

It's important with Spray-on Polyurethane to turn the can upside down after each use and spray for a few seconds until it hisses with little to no particulate being emitted. If you don't do this you will most likely block the nozzle between every coat. This can be super frustrating.

Step 6: And... You're Done!

Plug your lamp in and look for the pot of gold! My favorite outcome of this project (though entirely unintentional) is the rainbow shadows it casts! The lamp now sits proudly on a surface in a prominent spot in our bedroom.

Final thoughts...

I'm currently using a plug in wall dimmer I brought at a hardware store to adjust the brightness of the bulbs. I hope to find a nice rotary dimmer that will work with the led bulbs. I would like to mount this inside the lamp itself. Please let me know in the comments if you know of a specific dimmer that you think might work.

Also, I plan on routing a keyhole in the bottom of the base to utilize the lamp in both vertical and horizontal orientations displaying on walls.

Happy Pride Month, everyone!

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