by Joe Federer
Trælys is hand-made modern LED lighting with full brightness and colour control, made with carefully selected solid wood.
The Trælys light uses the latest in LED technology combined with the timeless appeal of solid wood. The current culmination of a long process of learning, discovery, and design, the Trælys light will provide you with a unique feature in your home or office.
The base of the Trælys is made from a block of solid wood. I have generally used maple, but any tight-grained hardwood is appropriate. The control sliders are on the top surface, next to the Acrylite Satin Ice cylinder. The LED ribbon is helically wound around a 0.5” dowel centred in the cylinder, and the cylinder is topped with a turned wooden cap.
History
When I was very young, my father introduced me to photography with various inexpensive but good quality SLR cameras. I remember spending many hours in the dark room, watching the magic of an image appearing on the paper under a dim red light. This process of discovery started a life-long fascination with light in all its aspects. At the same time, I developed an appreciation of efficiency and elegant design. When I was finally permitted to use my dad’s Leica IIIc, my appreciation of the qualities of light and of the qualities of good design came together.
Some time in the early 1980s I took advantage of my staff privileges to the University of Waterloo student machine shop to make the initial version of what would, 30+ years later, become the Trælys. I had long wondered if a standard fluorescent tube could be made beautiful, rather than harshly functional.
My first version was unique, but with the technical limitations at that time, still pretty harsh. The very first version is at the left of the opening shot in the video. My next version incorporated photographic gel filters, but there was no way to change the colour.
I designed a version with different gel colours on a roll, but never built it. Eventually I put away my test articles (until making the video!)
When LED ribbons became available, I ordered some and started playing with ideas. Even now, the technology is barely able to fulfill my vision. We have the capability of full colour spectrum and brightness control, but the brightness is not quite enough for use in general lighting. However, as a feature lamp, it’s quite sufficient.
An RGB (Red-Green-Blue) light requires a controller. With my background in designing custom electronics, a bit of internet research allowed me to create a custom controller that is simple and efficient. Modern limited-run custom manufacturing made it possible to do a sample run of the PCBs (Printed Circuit Boards) at a fully professional level. What a difference from the old copper-clad board and acid-bath days! At the same time, I had developed a fascination with wood through my work as an amateur luthier. The two came together in the first limited run of Trælys lights, which went to several family members and friends for evaluation and testing.
Current Design
The first versions of the Trælys where either just white, or RGB (Red-Green-Blue). Recently RGBW (Red-Green-Blue-White) LED ribbons became available at reasonable prices. This has led me to redesign the PCB with four channels. Even in the first design I decided to use linear slide potentiometers, simply because I used them while working in the audio/TV production field. In the interim, that design paradigm has become the standard to represent “Configuration Options”. This does create certain manufacturing challenges, but I think the end result makes it worthwhile.
I made the first limited prototype batch entirely by hand. I created a series of jigs for a router table, which allowed me to mill the solid wood base with a cavity for the control electronics. In the end, I needed eight different jigs to create each base. The process is very noisy and time-consuming. Each base takes well over an hour of machine work, not including sanding or finishing.
To match the base, I turn a top cap out of the same type of wood. This has to match the outer diameter of the light tube exactly, so it also takes quite a bit of time to get just right. Turning the top cap and finishing the wood takes another half hour
I made the decision to use a standard external wall-wart to eliminate electrical certification issues.
Technology
The control electronics board uses a custom designed PWM (Pulse-Width-Modulation) circuit of four channels. There are two LM324 Quad op amps and four IRF530 Power MOSFET transistors. The first four op amps act as a triangle-wave generator running at about 117 Hz. This signal is fed to each of the colour channels, where each segment of the second Quad op amp produces a square wave, the duty cycle of which is determined by the slider potentiometer. The resulting square wave feeds a single IRF530 Power MOSFET transistor per channel, which boosts the power to a level that will light the appropriate section of the RGBW ribbon. The LED ribbon requires 12 VDC, at up to 660 mA for the RGBW strip, or up to 940 mA for the white-only strip. The IRF530 transistors can handle up to 14 A continuous, so there is lots of room for higher power strips as the technology improves. The end result of all this is that the LEDs are turned on and off 117 times per second, the on-time controlled by the slider potentiometer. To the human eye, this looks like a change in brightness. All dimmable LEDs work this way, since LEDs are by nature either on or off. 117 Hz is a high enough frequency that there is no visible flicker, and low enough that it can’t be heard.
The light is produced by LEDs surface mounted onto a 9 mm wide Mylar strip. The strip is helically wound around a 0.5” wooden dowel. In future I may use a standard copper water pipe for other projects I have in mind, but in this case a non-conductive surface simplifies things. The dowel is then inserted into an Acrylite Satin Ice acrylic plastic tube. It is held in place at the top by the end cap, and at the bottom by a hole in the base. The LED wiring is run in an expanded section of the dowel mounting hole into the components cavity. The Acrylite tube diffuses the point sources of light produced by the individual LEDs, softening the light and making the tube appear to have a smoother glow.
Materials
The prototype circuit board and some components contained small amounts of lead. The Panasonic slider potentiometers I used then are now not readily available, but the Bourns versions are readily available (in substantial minimum order quantities) and are lead-free. Likewise, any new PCBs are lead-free. As long as all soldering is done with lead-free solder, the entire resulting product is RoHS compliant. The wall warts are all RoHS compliant. They are available with the common (North American/EU/UK) plug configurations.
The LED ribbon is Mylar with surface-mounted LEDs. The ribbon is also RoHs compliant.
The Acrylite cylinder is food-grade Acrylic plastic. It is fully recyclable, UV resistant, and doesn’t show fingerprints. The top cap and base are made from solid wood. I generally use Maple, although Walnut and Cherry would be good as well. Certain exotic woods can be used, as long as they are hardwood with a tight grain and are available at least 2” thick. The base is 2” high, requiring an unusually massive piece of wood. The components cavity is machined out of this solid block using a router. The wood is finished using multiple coats of a tough Urethane finish.
How bright are Trælys lights?
These ratings are based on published specifications of the LED ribbons used.
What can I do with the Trælys light?
You can use it as an accent light in any room in the house. I find it makes a great night table light, setting any mood required. At maximum brightness, you can use it as a reading light. The RGB and RGBW versions make great teaching aids for demonstrating additive colour theory. The 1 metre tube light makes a great display light for trade booths and shows at night. In short, the Trælys light can be used for just about anything that doesn’t require more than 700-900 lumens, which is the brightness of a traditional 60W incandescent bulb.
Rewards and Shipping
I have enough components in stock to fulfill the Early Bird rewards. I will order components for all other levels as soon as this campaign is successfully funded. Delivery of the PCBs is within about a week, but the other components may take longer. The most time consuming part is making the bases, so depending on the number of rewards required, this can take some time. The first three reward levels are small packages that will be shipped quickly. The fourth through seventh reward levels are one box each with dimensions of 8x8x17 inches, and will be shipped via Canada Post/USPS. The eighth reward will be shipped in three individual boxes, or one big box if that’s more economical. The top three rewards will be shipped in the most practical and economical way possible.
The 1 metre tube light in the top three rewards is a special limited version of the RGBW Trælys light tube, but is 1 metre long with an external controller box connected by a single cable. It will be shipped separately in the safest and most economical way.
Why Kickstarter?
I self-funded the prototypes. To move into larger-volume production will require an investment in production machinery. A good quality jointer/planer will simplify the dimensioning and finishing of the wood bases. A CNC router will allow the carving of the component cavities to be semi-automated, saving at least an hour of noisy, tedious work per unit. Neither of these machines goes for pocket change. Lastly, some components are very expensive in small quantities. Electronics component prices become much more reasonable when ordering at least 1000 of anything. Even the Acrylite plastic tubing has a fairly high minimum order quantity. The funds raised in this Kickstarter project will allow me to purchase the essential production equipment and order components in cost-effective quantities. This project will allow the ongoing development of unique LED based accent lighting which will be featured at www.traelys.com
International Backers
The only part of Trælys that is country specific is the power adapter. When you fill out the delivery survey, you will be able to specify which plug style you need out of the North American/EU/UK options. If you need an adapter other than one of these three, please let me know and I will try to find one suitable, or you can find one locally. The barrel plug dimensions are 2.5mm I.D. x 5.5mm O.D. x 9.5mm and the output is 12 VDC at up to 1 A for a rating of 12 W. Shipping is also more expensive outside Canada, therefore, a shipping charge will be applied outside of Canada. In all cases you will be responsible for GST/VAT and import duties.
Schedule
I have specified all parts and identified sources. In all cases, I have dealt with the same reputable suppliers for the prototype phase. Lead times are reasonable for all components. The challenge will be to make and assemble the lights. Even with a CNC router and series production, each unit will require about 2.5 hours. The Early Bird units can be in your hands within 2 months of the project successfully closing. The main production units will be shipped as promptly as possible, depending on how successful this project is. I aim to deliver sooner than specified at each Reward level.
Although I have identified reliable suppliers and have dealt with them in the past, nothing in supply chain management is for sure. So Risk #1 is that there may be unanticipated parts-delivery problems. Risk #2 is that this campaign is so successful that the sheer volume of rewards will take a long time to fulfill. I do all parts of the process myself, although I can call in help with things like PCB assembly and shipping. I suppose that Risk #3 is that something truly unanticipated occurs, such as a major natural or human-made disaster or postal strike. In such a case finishing this project will not be the highest priority. Having said all that, it is my firm intention to deliver all rewards as quickly, accurately, and carefully as possible.