Kickstarting the HexBright: Adventures in Flashlight Hacking

Kickstarting the HexBright: Adventures in Flashlight Hacking

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HexBright creator Christian CarlbergChristian Carlberg is a Cornell-educated mechanical engineer. After his undergraduate degree, he spent three years doing classical aerospace work and getting an MS, part time, at night school. At 25 he moved to LA to work in movie FX, specifically “practical effects”—physical, animatronic robot-based puppets now in decline thanks to low-cost CGI. After that, he moved on to show-ride engineering for Disney, where, among other projects, he worked to make the 6-foot diameter giant squid eyeball at Tokyo Disneyland’s 20,000 Leagues Under the Sea attraction light up. He left Disney to become a regular and successful contestant on the TV show BattleBots.

comingtobayareamakerfaire_2013These days Christian works in commercial robotics at Palo Alto’s Suitable Technologies, developing a sophisticated remote telepresence system called Beam. Since 2011, in his free time, he’s been leading a small team (two initially, now expanded to six) to design, develop, manufacture, and distribute the world’s first fully open-source, user-programmable high-performance LED flashlight.

Christian’s a busy man, by anyone’s standard, but I got a chance to catch up with him last month and get his insights about what it’s like to successfully crowd-fund a hardware development project with a very small team.

You originally launched the HexBright project at Maker Faire, right?

Correct. I made the Bay Area Maker Faire 2011 my target date to launch HexBright on Kickstarter. I enlisted the help of my friends to get a website together along with video and pictures. I literally filmed my promo video the day before Maker Faire and launched on Kickstarter the first day of the Faire. I spent both days at the Faire handing out fliers. Most people were interested, but more than a few people were skeptical. That’s OK, I’ve been called crazy before.

Your Kickstarter was hugely successful.

When funding closed, eight weeks after the Faire, HexBright FLEX had raised almost $260,000, making it one of the top ten most-funded Kickstarter projects at the time. I had more than 3,000 backers. Mythbusters‘ Grant Imahara gave me a video endorsement!

YouTube player

You started with the idea that you wanted to do a Kickstarter campaign, and then decided an open-source flashlight was the right project for that purpose. Why?

Three reasons: One, I had some LED experience, from my time at Disney Imagineering. Two, a flashlight is an interesting blend of multiple disciplines—mechanics, electronics, battery management, optics, as well as aluminum and plastics manufacturing. Three, I had an interesting idea about how to seal the micro-USB port.


Tell me about that, the USB seal.

You will note that the inside carrier threads are at the front, which draws the rear o-ring to seal against the body. I thought it was a great way to have a rechargeable flashlight with very good sealing. It’s a four-start thread, by the way; there are four separate grooves which overall makes it very coarse. But it seals tight and in one revolution you have access to the micro USB plug.

Why did you decide on open source?

I looked around and saw that no one had really done it. I realized I had a niche market.


What qualities of the flashlight are programmable?

You can think of it as having three inputs—the rear button, the little black reset button on the board, and the accelerometer—and three outputs: the main lamp (which is a CREE XM-L U2, the best available right now), a rear green indicator LED, and and a rear red indicator LED.

The light includes an accelerometer? What for?

Whatever the heck you want! Part of the idea was that I wouldn’t program anything but let “the wild” figure out stuff. I supply the tool, you supply the creativity. People are putting programs on Git Hub.

But at some point, during the design process, there must’ve been a moment when you said, hey, let’s put an accelerometer in the thing…

Actually, that idea came from the backers themselves, in the very early days. Sure, it costs more to put the part on the board, and I don’t use it at all in the factory-installed program. But it’s there if you want to hack your light.

So the design evolved during the funding cycle.

I originally offered two designs: a simple, small, cheap flashlight with a cool grip design, and a big, more expensive, open-source flashlight, thinking most people would want the smaller one. I was waaaaaay wrong. Everyone wanted the cool open source design.

Custom aluminum extrusion

You had a custom aluminum extrusion made for the body. Had you done custom extrusions before? How did you find the manufacturer for that?

Yes, I’d done it before, but it’s actually pretty easy. You just make a drawing and a .dxf file of the cross section, and send it to a shop for feedback and a quote. There are a ton of shops in LA and all across the country that can do it.

I recently saw a quote from the developer of the videogame FTL, which was a huge Kickstarter success, to the effect that he probably wouldn’t do it again because crowdfunding adds “a whole new layer of stress.” What do you think?

Yes, actually, that is true. There is a world of difference between having a finished product to sell and trying to design a project in front of thousands of eyeballs and potential complainers. You can’t please everyone all the time, so someone always complains. But right now all my US backers have a light and they love it. I always knew I could pull this off and make a quality product, but it took time to get there, and I had to deal with a lot of people constantly asking “where’s my flashlight?” It’s kind of like driving a busload of kids who won’t stop asking “are we there yet?”

What was the most fun part of the process for you?

The very start and the very end! The original design process, and shipping the units. Everything in between was a grind. I had to deal with suppliers, manufacturing issues, costs, Kickstarter backers, and general logistics. All very critical and challenging but not terribly creative. It was a fantastic experience for me, but every light that went out was a small load off my back.


How would you do it differently next time?

Offer fewer options, and ask for more money per reward than you think, but still slightly less than “retail.” Try to get more homework done ahead of time. I used Kickstarter as it was originally intended—as a platform for project development and not so much as a store. As a result, I literally started with a rough idea and developed it all the way through to a product. That takes a long time and a lot of effort, especially when you’re also holding down a day job, as I was. I am pretty pleased that in my spare time I created a quality product in the same ballpark as big, multi-million dollar name brand flashlights.

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34 thoughts on “Kickstarting the HexBright: Adventures in Flashlight Hacking

  1. Timothy Gray says:

    and ask for more money per reward than you think, but still slightly less than “retail.”

    Yeah, ask me to risk my money on your idea and reward me with “slightly less than retail”? Good way to make sure a kickstarter dies on the vine. Far roo many of these people look at kickstarter as a sales generator and not a micro invester to get funding to get started. If he messed up and did not calculate costs correctly to begin with, oh well. But if you expect profits off of the kickstarter? That is just plain old wrong.

    1. Sean Michael Ragan says:

      “Yeah, ask me to risk my money on your idea and reward me with “slightly less than retail”?”

      Um, yes? Don’t understand why that idea seems so upsetting to you.

      “Good way to make sure a kickstarter dies on the vine.”

      Don’t see why. Can you unpack?

      “Far roo many of these people look at kickstarter as a sales generator and not a micro invester to get funding to get started.”

      Christian did just that. HIs case is exactly the opposite of the “sales generator” scenario you inveigh against.

      1. JD90 says:

        ““Good way to make sure a kickstarter dies on the vine.”

        Don’t see why. Can you unpack?”

        Unless the person setting up the Kickstarter (or IndieGoGo) has an actual track record, asking nearly full retail price is frankly asking a lot for something that might never become a real thing or not actually live up to its billing. A decent discount is not too much to ask for backers to expect.

    2. Edward says:

      I think what he meant by that was charge your backers less than retail. In his case he charged *way* less – a boon for backers but gave him no room for production costs like prototyping, rework and packaging. I think it’s a good idea to let your backers get a cool new product for less than the eventual mass market. For my latest Kickstarter project I was very open with the backers about where the money was going, including publishing a spreadsheet. I also made sure to calculate gross margin per item against estimated costs. My effective gross margin was around 50% after funding the rewards, to be used directly for project support. It’s a balance but as he says – do your homework before launch!

  2. Jim says:

    What would have made this a lot more interesting article would have been a couple or examples of creative uses people have come developed. As is we’re left with the mildly interesting idea that we could change the brightness level or something similarly mundane. It’s entirely plausible that people have come up with all type of creative niche uses for it.

    Yet, there’s nothing. This leads me to believe there really may not be much useful that anyone has come up with beyond some minor and largely irrelevant tweaks. I’m especially surprised there was nothing on the website touting any community designed mods.

      1. Jim says:

        Thanks, that does show more about whats going on. However, if that’s the best available it’s not exactly impressive. Just glanced at it and really didn’t see much except descriptions such as, Fred’s Hexbright code or My Hexbright code. Sure if I already owned one I might spend the time to open up each one of those in the possible hope they had something cool but that’s not very realistic for most people considering buying one. There were literally a couple out of the 25 projects that had descriptions that actually told what they did and most importantly seemed somewhat interesting.

        I’m not slamming the idea of the Hexbright at all. I’m just saying it seems pretty weird to put out an article touting a programmable flashlight and then not provide any examples of actual customization. It’s really strange for the manufacturing website to not provide that!

        1. Steven says:

          Hey Jim, I could go into details, but basically there’s two things to consider here…
          1. The official website is pretty much run by Christian, so any new content that should go up there – such as links to resources, full schematics, etc – is up to him.. and right now he’s busy just working his regular day job and getting the lights out to people (UK shipment up next).
          2. It’s a flashlight. Have it blink morse code, have it increase/decrease in brightness based on a twisting motion, have it blink brightly when dropped (or tapped), etc. but it’s still a flashlight. While I plan to add a buzzer to mine in order to add auditory capabilities, it’ll still be a flashlight – albeit with a buzzer – and certainly won’t be replacing my phone as a podcast player. Now, don’t get me wrong – it’s still easily the most advanced flashlight that is commercially available, but ultimately there’s only so much you can do.

          In the end, I’m hoping this will help make more flashlights be programmable – even if not open source – because having brightness settings that aren’t exactly to my liking, or a strobe mode that is just a pinch too slow, or too fast.. is something that is now an addressed problem and there’s little excuse to being stuck with established manufacturers’ choices. Most people aren’t going to care, of course, but they wouldn’t be the target market anyway :)

          1. Jim says:

            That makes sense. I realize the article author has no control over the sales site but did think that it was sort of missing the fundamentals of showing the advantages of a programmable flashlight if that is what he’s trying to sell.

            Your explanation here was a lot more reasonable to me than the article. Nothing wrong at all with a flashlight where you can tweak the settings to your desire. The article, and it may just have been the author’s enthusiasm leaking through, seemed to say that people were coming up with all kinds of innovative uses. I couldn’t think of much personally beyond what you just said so thought I must have been missing something.

  3. rocketguy1701 says:

    I encountered Christian at that Maker Faire, and later bought in at the kickstarter. While I salute him for following through and making sure the end product was right, the time taken was *extremely* long. I’m glad he acknowledges that, I would not call this a shining example of how to do a kick-starter.

    I wasn’t one of the complainers, as I understood what the deal was, and I never asked for an ETA, figuring it’d get there when it got there. That said, by the time it arrived, I wasn’t jumping in glee, I was more “wow, it finally showed up”.

    The end product was slightly fatter than the original spec, which wasn’t great for putting it in my already overloaded tool holster, and the accelerometer is somewhere between a gimmick and actually useful. It can be useful, and I do use it occasionally, but the usb charging is probably far more important.

    I have loaded two programs into it, and will likely will mash up some of the existing sketches out there into something I find usable, and then leave it be for the rest of it’s design life. But, having it work the way you want can be compelling. I wouldn’t expect a vast library of code for what is, in the end, a flashlight, but there are already some interesting sketches.

    Obviously, you can get one now without the rather excessive wait, so if you want an efficient, well built programmable flashlight, with good brightness, by all means, go for it. It won’t change your life, but it will do the job, (your way with some effort), and the build quality is good.

  4. Mathijs says:

    Christian is a little of the truth with the comparison with the bus full of school kids. That is because he originally estimated that the lights would be shipped by the end of 2011. Now we are in the second quarter of 2013 and I personally still don’t have a light. That is like telling the school kids that the playground is just 15 minutes away and then drive for several days. By the way, I still agree that we are going to disneyland and not a small playground.

  5. Bruno Reyntjen says:

    Where is my light??? 2 years after the kickstarter project begun my light isn’t here yet. Christian, sorry but you are an amateur. You have underestimated everything you could under estimate. And 2 years later your international investors have not been served yet!

    This is where you make an error again. You are dealing with investors and not clients. Ask Disney if their investors complain if they will treat them as “a bus full of small children”. I know a lot of people who will never buy a product from you again.

    You may have a great pruduct without satisfied customers you will not get there.

    1. Steven says:

      Bruno, you know you’re commenting on an interview piece and not actually sending a message to Christian, right?

      I don’t know where you’re living, but every US and CA backer should have theirs, AU and UK are currently receiving (depending on speed of postal services to them), and some DE and NL backers have gotten address confirmation e-mails so those should be coming up shortly as well. Yes, it’s been a long time since the project funding was finished, but they’re being shipped out and – as with a bus of children asking ‘are we there yet?’ all the time – they’ll get there when they get there. And no, I haven’t gotten mine yet either, so I do sympathize.

  6. JD3 says:

    I still don’t understand the point of the custom aluminum extrusion. Hex is a commonly used shape, and it’s available in a variety of sizes and alloys.

    1. Steven says:

      Christian addressed this in the original project video, if I’m not mistaken. The prototypes were made from solid hex bar stock, but he suspected it would be cheaper to have a hex extrusion with the circular cut-out down the middle done, than it would be to drill holes through the solid stock for the expected number of lights (nevermind the number of lights it ended up being). I don’t know if he went through with the extrusion route, though.

  7. scarpe hogan donna says:

    You write very well

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I am descended from 5,000 generations of tool-using primates. Also, I went to college and stuff. I am a long-time contributor to MAKE magazine and My work has also appeared in ReadyMade, c't – Magazin für Computertechnik, and The Wall Street Journal.

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