Aquarium LED Light Crane

prusaprinters

<p>This is a DIY Aquarium LED Light with variable length and light intensity.<br>Distance to the top edge of your tank is fixed to 10cm, but the length of the arm depends on your needs.</p><p>I'm using it with an 32cm long arm, but you can make it longer if you want. Althoug there will be a point on which the counterweight will get so heavy, that it might damage the 3D print or even the glass of the aquarium. Be careful.</p><p>I built myself several LED lights for my planted aquarium over the last years and finally wanted to share a design.</p><p>I wanted to cover as little of the tank and the water surface as possible, so I designed a crane-like LED light.</p><p>In the original design the arm of the crane did hang down a bit, and I was also afraid that over time the PLA will break from the stress. So I designed the whole light with a counterweight which depends on the weight of the arm and its length.</p><h3>What you will need for this project:</h3><ul><li>Aluminum Profile 40mm x 3mm x length of your light</li><li>12V LED Strips (I'm using warm white, cold white and a bit of red)&nbsp;</li><li>12V power source for the LEDs and a way to connect them to it</li><li>1m string</li><li>1 plastic bag and gravel or similar for the counterweight</li></ul><h3>How to build it</h3><p>First off, print the parts you need. I've designed parts for the corner and for the side of the tank with 4mm, 5mm, 6mm and 8mm glass thickness.<br>Print one of these and the endcap.</p><h4>The LEDs</h4><p>Measure the length of your tank and determine how long your light should be. I usually don't let it go over the entire length.</p><p>Cut the aluminum profile for that length plus 20mm which will go into the mounting.</p><p>Now you have to think about how much light your tank needs. This highly depends on the type of your aquarium, if you are having loads of plants, Co2 injection, size, amount of natural light the tank gets and so on.</p><p>Often you'll get recommendations in Watts per Liter(or Gallon) and they are meant for fluorescent lamps. LEDs are much more efficient and will give transmit the same light with fewer watts, LEDs transmission is measured in Lumens.</p><p>Depending on your tank you'll need 10-60 Lumens per liter. The LEDs I'm using have ~15lm/LED. Now with your aquarium size, Lumens per liter and your LEDs you can calculate how many LEDs you'll need, how long the strip will be and how you will arrange it on the aluminum profile.</p><p>For my lights I already played around with red, blue, RGB, warm white and cold white LED strips trying to archive a good spectrum for my plants.<br>What worked best so far is warm and cold white stripes and a short stripe of red.<br>I think this is, because white color LEDs are basically blue LEDs with a fluorescent coating on them. The coating absorbs loads of the blue light and emits it in a full spectrum.<br>I'm not sure if the red strip really does anything here, but I figured it won't hurt.</p><p>Now glue the strips on the aluminum profile and leaf 20mm on one and 15mm on the other end. Also leaf enough space to solder and connect the LED strip to your power source.</p><h4>The Counterweight</h4><p>After you've assembled the LED arm you can now calculate the counterweight. I'm fairly new to static and have neglected any friction or the weight of the rope, still I think that for small use cases, like here, this doesn't matter.</p><p>First we'll need the angle of the rope, this only depends on the length of your arm.<br>The angle alpha=artan(60/[arm_length_in_mm]).</p><p>After that we can calculate the counterweight, it depends on the angle and the weight of the arm.<br>Mass of the counterweight m=[arm_weight]/(2*sin(alpha))</p><p>Now fill the plastic bag with enough gravel, that it has the right weight.</p><h4>Assembly</h4><p>To assemble the whole light put the LED-arm into the slots of the endcap and the crane.<br>Connect one end of the string to the endcap and the other to the counterweight.</p><p>Now plug your power source in and enjoy the new aquarium light!<br>&nbsp;</p>