Modern Hexa LED Lamp With Bluetooth

Hello,

Today I'm glad to bring you a new stylish LED lamp. I made this 94W lamp to illuminate a big room with a kitchen and a living room for a total space of around 7 x 5 meters.

The lamp is made of painted high-quality wood and it includes a dimmer that allows to use an app to change the intensity of the LEDs via Bluetooth.

I also made a smaller 24W lamp to lit the entrance of the house which is a smaller space of 1.5 X 2 m.

The Hexa LED Lamp with Bluetooth is an evolution of my instructable Honeycomb LED Panels. I used finer and stronger wood this time, oak and liden, instead than fir.

I started with a few ideas combining hexagons and I decided to pick a sketch among a few.

I designed the aluminum base of the lamp. Each side of the hexagon is 23cm.

I included in the drawings also the screw holes to make it easier to assemble and I included several bigger holes to pass through the main wires. Attached you find the DXF files, which are needed for the laser CNC to cut the aluminum. I asked a company in my local area to laser cut the aluminum for me.

Regarding the wood I decided to cut all equal pieces of battens and strips with a 60° angle. I included recesses to arrange the magnets. The depth of these recesses depends on the height of the magnets. I ended up using magnets 3mm high.

Mechanical supplies:

- laser-cut aluminium plate 2 mm thick
- 2 pieces of oak wood batten 5x2x300 cm
- 10 pieces of liden wood strips 2x2x100cm
- round magnets 10mm in diameter 3mm thick
- small steel plates for joints
- 1 piece of fir wood batten 5x2x100cm

- 1 foil (100x80cm) of opal polycarbonate 1mm thick

- opaque black paint for wood

- wood filler

- Self-adhesive support for white cable ties

- Cable Clips with Nail

Electrical supplies:
- 4 pieces of 35W 24V power supplies for LEDs
- 144 modules at 24V 0.7W (36 modules each hexagon). The length of a module is 60mm (also strips can be used). Neutral white (4000K)

- 4 pieces of Schottky diodes 100V 5A

- Bluetooth Dimmer 24V

- 2 pieces of 15W 24V small power supplies for LEDs (used for the small hexagon)

All the wood has been cut with the manual saw as you see in the picture and sandpaper was used to smooth the edges. You can also use a miter saw to be more precise but be careful!

I have used the aluminum plate as reference template and glued the liden wood frames together using only PVA glue. Be patient and you will see that the PVA glue is extremely strong on wood once dried.

After a few hours, once sure that the PVA glue had dried and the junctions were very stiff I have filled the grooves with wood filler. The quality of the wood filler is important here for a good finishing. I found a wood filler that simulates well also the "hairs" of the wood.

As first thing I suggest you to countersink the holes in the aluminum on the side where the countersunk head screws will go.

Then place the oak batten on the side of the base and drill a hole in it, in that hole you will more easily insert the screw to fix the batten to the aluminum. To make sure you are precise use a couple of table clamps, so the wood pieces remain still while you drill and screw. Another approach is to glue with PVA glue also the battens together and then place them on the hexagons and drill the holes.

As you can see from the last picture in this step, we will also make sure that the aluminum plate is earthed, just twist some copper wire around a screw before screwing it and it will make contact with the aluminum plate.

Even the more precise job can let behind some grooves between the pieces of oak wood. Not a problem, just fill the grooves with wood filler (use a spatula or your finger) and once it has dried up just use a little bit of sandpaper to smooth everything.

For the reason that the frames had only four supports each, for magnets I decided to use two magnets each hexagon side to make sure that the frames where well fixed to the base sides.

I have signed the holes with a pencil at around 3.5cm from each hexagon corner.

I really suggest using a wood drill and to place a piece of tape on the drill so you know when the recess is deep enough. Just be careful not to exaggerate with the depths of the hole and try to let the magnet tip come out a bit (0.3mm).

A little hint is that if you make a mistake and the hole is too deep, don't worry, just put some sawdust inside the hole and then place the magnet.

Before starting to paint the lamp I suggest masking the aluminum, so you will not dirty it if a few paint drops fall.

I have a used opaque black paint with white spirit as a diluent. But you can also use a water based paint which is more eco-friendly.

Once the paint is dried, you can screw back the magnets in their original positions.

Use black acrylic spay to colour the plates and then screw them to the wood frames as seen in second picture.

The function of the steel plates is also that they keep the opal cover fixed down on the frame.

I hope you like the case. Now we just have to place LEDs and power supplies inside the lamp to light it up.

The total LED load is about 100W and as my designed included a dimmer all the current had to flow from it. The dimmer I chose can handle up to 10A of current. To choose a power supply we have to stay at leat the 20% above the total load power but a power supply of 120W would have been too big. So I decided to use 4 pieces of 35W power supplies connected in parallel and then I designed the circuit you see in the picture. If we were building a normal on/off lamp we could have used a single power supply for each LED hexagon but in this case, as all the power supplies had to pass from the Bluetooth dimmer, I had no other choice than to connect them in parallel.

It is often unadvisable to place constant voltage power supply in parallel, especially if are different brands and models, because output voltages may vary between them and even if variation is of only 0.1V, one power supply will work more than another or completely take over another. The output current of one power supply could enter into the output of another power supply, reducing the current of the latter. To avoid this, it is important to place Schottky Diodes in series with the output as showed in the schematics and always use certified LED power supplies of the same model.

Certified power supplies will automatically switch off if their inner temperature will rise too much.

A diode is an electronic component that blocks the current flowing in a verse. A Schottky Diodes is designed to limit the voltage drop to minimum when current is flowing through it. As you see in the schematics the diode voltage drop is around 0.6V, which is quite acceptable considering this is a power application.

I have used brass wire to make the connection between the LED modules. I used an aluminum hexagon as reference to be precise in making 3 LED hexagons, one would go inside the other.

The outer hexagon LED side is 3-module long, 6cm each module for a total of 18cm.

Use small wires to make bridges between the LED modules. As always, it is very easy, positive (+) with positive (+) and negative (-) with negative (-).

Glue the power supplies and dimmer to the aluminum with silicone. As you can see I had to modify a bit the dimmer casing to make is fit.

The general idea is that nothing has to block the light coming out form the lamp and the power supplies and dimmers must not be placed too close to the LED as they will project a shadow on them that will create a darker area on the opal cover.

Now we have to make all the connection as the schematics and we have to make sure they look nice. I have extensively used the wood as support for cable clips with nails and self-adhesive supports attached to the aluminum plates where I fixed cables with nylon cable ties.

I also screwed to the wood sides some plastic electrical terminal connectors to make all the junctions between the mains AC wires (brown for live and blue for neutral) and the 24V DC wires (red for positive and black for negative).

At last I connected the diodes, I used electrical terminal connectors to do so. Because these are power diodes I have used some thermal conductive tape to make them touch the aluminum plate that is acting as heatsink (you can also use thermal paste instead). We really want that these diodes will not move, so I used silicone to fix the electrical terminal to the aluminum base.

I have then switched on the whole lamp and did some measuring with my multimeter thermocouple.

It was a summer day (ambient temperature at 25°C). All the temperatures were very good.

The aluminum plate of the big lamp not even reached 30°C after many hours of testing. On the other hand the aluminum plate of the single hexagon reached 43°C, not much either.

The Schotty diodes measure all a steady 40°C while working from several hours.

Regarding the light emitted from the lamp it really depends on the LED efficiency. If the strips efficiency is the standard LED one, 100 lumen/W, and we estimate that the opal cover cut a 40% of light we can estimate the Haxa Lamp is a lamp of 6000 lumen.

I must tell you that at full power it was pretty bright.

Use Fischer plugs to fix the Hexa LED lamp to the ceiling and switch it on.

Test the smartphone app to dim it. As you might have thought, every time the switch shuts the lamp off, the Bluetooth dimmer will keep saved in its memory the last dimming settings. So when you turn it on again you won't have to change the lamp intensity again.

The Hexa LED lamp DIY project is finished and if you made your own lamp please share your design. As you can see with hexagon shapes you can really make any design you wish.

I think the Hexa LED lamp is now ready to be used to lit a very big living room.

If you feel lazy today why not just buying the lamp and avoiding the great fuss to make it. Ensure it on Etsy and I will make it and ship it to you in the colour you like the most.

https://www.etsy.com/listing/1148767076/hexagon-le...

Thanks for reading.

Bye from Merenel!

Pietro