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Sign Magic

Electromagnets levitate a sign honoring an electrical magician.

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Magicians create illusions to dazzle the eye and confound the mind. “And now I will make my assistant levitate above this table,” they might say, and then somehow, by magical power, the assistant floats up and remains suspended in mid-air. It’s a heck of a trick, a real attention getter.

My company, Sign Pro of North Florida (Alachua, FL) was invited to enter the 2017 (second annual) Sign Invitational (thesigninvitational.com) based on our body of work. The competition, which seeks “to foster involvement and creativity within the sign industry,” is displayed and judged during the ISA Sign Expo. The theme for this year’s Las Vegas-based competition was sign magic.

Per the rules, the upper portion was required to nest into a lower crate no larger than 24 x 24 x 36 in. for shipping purposes. The entire assembled piece could not be larger than 24 x 24 x 72 in.

 

TESLA TRIBUTE

Reverse-painted

We decided to pay tribute to Nicola Tesla, a brilliant inventor who once put on demonstrations like a magician and whose creations still shape our world. Our first great idea was to represent Tesla’s “magical” wireless energy and induction lighting by using magnets to levitate a sign. This idea would become not only the solution to, but also the creation of many problems we had to overcome.

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We invented a narrative for our piece: It was created and used by Tesla to promote his fictitious, early 1900’s wireless sign company. We named the company Tesla Electric Sign Company (TESCO) and built a website to support the narrative. [Editor’s note: Check out the testimonials at teslaelectricsigncompany.com for a laugh.] We also posted some progress pics, videos and other fun stuff on the site.

 

SCIENCE BEHIND THE MAGIC

We spent many hours researching how to levitate a sign. We weren’t interested in just a typical floating object, but rather one that would light up, seemingly based on wireless energy invented by Tesla. Then, we came across a newly developed method of balancing an object on top of a magnetic field. If we could execute this, our piece would actually levitate!

Briefly stated, the engineering involved a proportional-integral-derivative (PID) controller, a tiny computer capable of continuously sensing and adjusting the strength of electromagnets placed below the top portion of the sign, creating a state of balance – or, in this case, levitation.

 

THE TRICK OF LOOKING OLD

Now we needed to design and build our piece. We also had to highlight our fabricating abilities so our entry would stand up to the scrutiny of the industry leaders and educated visitors who would be voting in the Invitational. We decided to create a three-tiered design with classic colors and textures common in the early 1900’s.

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The lower tier would function as both a stand and a crate, but also as support for our story. Composed of PVC, it would showcase the use of v-carving on our CNC router. We hand-drew the vectors from the historical letterhead reference in Adobe Illustrator. A pocket in the top of the lower tier was routed to allow the middle tier to nest within it.

Lightning

The middle tier itself housed the levitation device and provided a rise in elevation to help present the upper (floating) tier at a more desirable height. We carved 3D watermarks of Tesla’s patent drawings for induction lighting and A/C electromagnets into the four sides of the middle.

The upper tier – our levitating sign –would be our showcase. We envisioned reverse-lit acrylic letters with prismatic HDU overlays gilded with 23k double goldleaf. The background of the sign had a 3D texture derived from a photo reference of leather and organic pebbles. The upper tier would also have an internally lit portion that was reverse painted acrylic to mimic alabaster, a popular design element of Tesla’s era.

 

MAGNETIC POWER

As we started to design our CNC files, we thought we might have bitten off more than we could chew. The upper portion went through three redesigns to arrive at the final design. The main issue we had failed to identify was how crucial the center of gravity was to the success of a stable levitation of the sign.

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The other major issue we were presented with was the transmission of power. Upon further examination, the power required to light the top piece was 5-6W. Transferring that much power over the distance we needed with our A/C electromagnets wasn’t possible. If we had increased the magnetic field enough for our power needs, that would have been enough to wipe out the credit cards and hotel keys of anyone viewing the piece. Instead we utilized energy-dense lithium-ion polymer (LiPo) batteries to keep the sign lit while also keeping size and weight within range.

 

“CAREFUL WITH THAT!”

In the end, we accomplished both the levitation and lighting of our sign. The final result was so seamless that much of the public didn’t even realize the sign was levitating! A few passers-by, seeing just the top of the sign turning slowly, mistook it for an attached, rotating sign and tried to give it a spin. This sent the top piece tumbling to the floor, much to the spinner’s horror. Had we made the entire sign a bit taller, the space between the middle and top tiers would have been more at eye level. Like Tesla, we’ll improve that for next time.

Plus, we may not have to wait long, as we’ve received considerable interest from clients ranging from biotech startups and colleges to an NHL franchise. All have been extremely excited to use this technology to boost their brand and image. We plan on bringing more levitating signs to market over time, so, as they say, for our next trick: Watch for our signs floating about.

Douglas

 

EQUIPMENT AND MATERIALS

SOFTWARE: Vectric Aspire, vectric.com; Adobe Illustrator and Photoshop, adobe.com

SUBSTRATES: DUNA USA CORAFOAM, dunagroup.com; Palram Palight PVC Trimboard, palighttrimboard.com; Piedmont Plastics Acrylic, piedmontplastics.com

ROUTING/CUTTING: CAMaster CNC router, camaster.com; Safety Speed panel saw, safetyspeed.com; Bosch table saw, boschtools.com

PAINTING: NovaColor, novacolor.com; Krylon, krylon.com

GOLD LEAF: Golden Leaf Products, goldenleafproducts.com; Luco gold size, uhlfelder-goldleaf.com.

LIGHTING: HanleyLED Solutions, hanleyledsolutions.com

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