On Beer and 3D Printing: Tap Handle Musings Part 1

If you have been following our social media accounts or exploits online, chances are you’ve witnessed multiple references to craft beer & roadtrips. We’ve also been guilty for using a #beerforscale next to our human scale 3D prints.

Chief Hacker shows off his super-sized 3D printed GE engine downloaded from Thingiverse using a Shiner Bock for scale.

As we’ve connected with makers across the globe, we’ve encountered a disproportionate number of other 3D printing enthusiasts who share a passion for home brews. Over stouts & porters (and an occasional hefewiezen), we began to muse with tap masters worldwide on the synergies between the additive manufacturing and brewing cultures, which revealed multiple overlaps.

Below are some similarities we’ve witnessed between our industries:

  • Brewers are makerpros too
    • Many of the tap masters we chatted with shared that their career started out as a hobby. A bucket and oversized pot quickly was upgraded to a small still, which serviced crowdsourced recipe requests for friends and friends-of-friends. Like so many of us now running 3D printing companies, successful breweries are an amalgamation of passion, friends, curiosity and a little hardware hacking.
  • Both movements are changing policy
    • As state and federal law restrict scaling microbreweries, many beer enthusiasts such as Raise Your Pint in Mississippi suddenly found themselves immersed in state politics as they lobbied for deregulation. 3D printing startups sympathize as we struggle to make sense of lack of industry specific export codes, open source policies, debate around the ethical use of 3D printers and the slow realization that the government is unprepared for exporting personal factories worldwide. An artifact of explosive growth, participants in both the craft beer & the 3D movement have accidentally found themselves immersed in policy & regulatory discussions.
  • 3D printing and brewing is as much an art as a science
    • While both of our industries are ultimately contingent on chemistry, whether it be polymers or yeast, little academic rigor has been applied to craft brewing or FFF 3D printing. We therefore depend on instinct and basic scientific probing to ensure consistency & quality.
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  • We’re building factories
    • Whether you’re making a bottle of beer or a Gigabot, once you commit to commercialization (even in limited quantities), you’re forced to stand up shipping, compliance, and production. Within a few months, a small-scale factory emerges, with an impressive infrastructure investment (usually from the founder’s pockets).
  • We need significant capital outlay, that often is accomplished without a VC
    • With the exception of growth stage breweries (e.g. Laganitas), most microbreweries are intentionally small. As non-traditional business owners we chatted with borrowed from their 401K’s, installed the best investment apps uk, and got loans from families to bring their dream to reality. Not surprisingly, most founders we encountered were in their 30’s, 40’ or even 50’s, having accrued a nest egg to overcome the risk and initial expenditures. Breweries, like 3D printing start-ups tend to gravitate to non-dilutive options for initial funding and seemed more concerned with making a sustainable business than posturing for quick acquisition.
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  • Our cultures represent a lifestyle & community is core to our mission
    • Let’s face it.  No one wants to drink alone. Concurrently most hobbyists are only as successful as the last 3D print they shared publicly. Start-ups in both domains have calendars full of events to engage enthusiasts of all levels, because the heart of what we do includes sharing and dialogue. Yoga and trivia nights are no stranger to local breweries. Similarly most 3D printing start-ups host regular meet-up and grass roots efforts to provide education, good WiFi and a place to swap ideas.
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  • Tap handles make a perfect 3D printing project for budding breweries
    • Stay tuned for Part 2 of our Beer & 3D printing series!

~Samantha

Improving Your Manufacturing Equipment with Gigabot

Below is Gigamachinist Steve Johnson’s second blog on 3D printing for re:3D’s Gigabot fabrication shop.

Improving Your Manufacturing Equipment with Gigabot

by Steve Johnson

Sometimes, you have a product that works, but there is a way to improve it to make it work better.

A few months back, we added a 4th axis rotary table to our mill at re:3D. It has allowed us to begin to capitalize on the full milling envelope of our machine, allowing us to mill as much as 8 times more parts per program cycle, and reduced the need for multiple operations on some parts.

We quickly found a weak spot in our rotary table though. The table was designed without any seals to prevent shavings from entering the gearbox. As a result, we have had to disassemble the rotary table twice now in order to clean out aluminum shavings that had bound up in the worm gear. We decided this time, that we needed to find a solution for this issue, to keep our mill up and running longer between needed maintenance.

Once we had the rotary table apart, we found the area where the shaving were getting into the gearbox. There is a groove in the back of the table section, and a boss on the rotary body that rides inside the groove. But the fit between the two, once assembled, is very loose, and will allow anything smaller than .1 of an inch to pass through. Obviously we needed some type of o-ring, or gasket in order to seal this gap, without creating unwanted friction.

A few quick measurements, and Matthew headed to the computer to create a short profile on Solidworks, that would fill the gap. Using Ninja semi-flex filament from www.ninjatech.com, we made a first print of that profile on Gigabot, and took it to the shop to test fit. It was a little tight, so back to the computer to adjust a couple dimensions, and another short profile print. Once we had the right fit, we revolved the profile into a full circle on Solidworks, and 15 minutes later, we had a custom made flexible gasket that seals the rotary table from chips without creating drag on the axis motor.

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We found a problem. We imagined a solution. And with Gigabot, we made it a reality today.

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Now we are back up and running so that we can manufacture the parts for YOUR new Gigabot.

Happy Printing!

  • steve@re3d.org

Designing a Transformer Toy

The great thing about designing a huge 3D printer is being able to support your friends & family bringing their ideas to life. Below, Nathan, the nephew of Chief Hacker describes how he designed this awesome transformer toy that was printed on Gigabot in one print job.

This transforming robot was based on transformers kids toys. I had played a lot with Transformers toys in the past and desired to make my own design. The concept of pieces held together by elastic was inspired by some transforming wood toys that I had seen on the internet. Before making this design I had experimented with making robots figures similar in concept out of cardboard and rubber bands.

~Happy Printing!

Nathan aka Na Gr

  • Reach me at on G+: https://plus.google.com/118159598743335846845/posts or email my uncle at matthew@re3d.org:)

A Beginner’s Guide to Scaling Your Favorite Print

Odds are if you have a Gigabot you've discovered that the only thing better than 3D printing your favorite open source model, is printing it as big as possible!  In honor of Independence Day, we've scaled an impressive scan of a Statue of Liberty to almost two feet tall, while highlighting a couple of tricks we've learned along the way:).

Step 1: Find Your File

Knowing I wanted to print something patriotic, I conducted a quick search for “statue of liberty” on Yeggi, which yielded multiple results spanning several 3D file sharing platforms.  The Statue Of Liberty Bronze Model by jerryfisher quickly caught my eye, and being a huge Sketchfab fan, I clicked on https://skfb.ly/CONx. The impressive scan of a bronze Statue of Liberty had been downloaded over 200 times and the creator has produced several other awesome files, giving me confidence the file was print worthy.  I was also pleased to see the file was available for sharing through redistribution through Creative Commons licensing.

Step 2: Optimize for Large Scale Success

Once I downloaded the file, I opened it in Simplify3D, our preferred visualization and slicing tool. While centering the file on the build plate and inspecting the print, I noticed the bottom of the design had a slight curve. As I desired a level base to better support the future large statue, I borrowed a trick from Chief Hacker’s cheatsheet.  By lowering the print slightly into the bedplate until the upper part of the coven curve hit the platform, I was able to “cut off” the curved portion of the bottom, rendering it flat after slicing.

Due to the multiple overhangs (including Lady Liberty’s arm), the design required signifiant support material. Based on experience, I recalled that support material over 12 inches could be a little unstable, but after consulting with Chief Hacker, I learned this could be overcome by adding a -45 degree support angle in the support tab of Simplify3D. By alternating the angle, the supports would have more structure and be less wobbly.  I also decided to add a process setting to decrease the speed when printing the crown in order to give the tips more time to cool after seeing some prior fails with similar geometry.

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With these minor manipulations, I was ready to slice and get started! Two filament swaps later I was loving the out-of-filament detection feature on Gigabot Generation 3.0 and diggin my very own Statue of Liberty. Admittedly, it took a little time to remove the extensive support material (and I broke half of a piece of the crown), but the end result was more than worth it!

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Step 3: Personalize Your Masterpiece

The only thing missing was Liberty’s iconic color, which I sourced after a couple of trips to local hardware stores. Sea Mist Rustoleum metallic spray paint did the trick and resulted in a great finish! We’ve had the most luck using spray paints intended for plastic when post-processing PLA, but find dry times between coats need to be extended (or at least when spray painting in the Texas humidity). Also, be sure to remove all the support material before applying a coat of paint as all support artifacts stand out when coated!

We love having our own Lady Liberty in our Austin office.  Huge thanks to Jerry Fisher for sharing this fabulous Statue Of Liberty Bronze Model licensed under CC Attribution!
Want to download the file? Check out https://skfb.ly/CONx

~Happy Printing!

Samantha: @samanthasnabes

Making a 3D Printed Bicycle Prototype

Last summer, Patrick Fiedler developed a 3D printed bicycle prototype for his summer internship.  In his own words, he describes his design process:

Have you ever wondered how 3D printing, renewable resources, and transportation all fit together? Although there many possible combinations, one instance is the 3D printed bicycle project that I worked on last summer. I had the wonderful opportunity to intern at re:3D in Houston, Texas and got the chance to work on this awesome project with the intention of answering this question: Is it possible to 3D print a working bicycle? I set out to do just that. With the large format possibilities of the Gigabot and wide range of filaments compatible with the Gigabot’s re3D hot end, I had the means to get started answering this question. The following is a brief review of my project that I wanted to share with the 3D printing community.

First, I deconstructed a MGX bicycle I found laying around. I analyzed its components and assembly mechanics thoroughly. I had to decide what could possibly be replaced with customized 3D printed components. The most likely option was the frame. With the customizability that comes with any 3D printed piece, I could easily use the modular nature of bicycle parts to attach them to my frame and roll from there (hopefully literally).

I set out to choose a good filament for frame construction. Thankfully, I had already been making ASTM tensile test samples for research re:3D was doing with Dr. Scott Fish at the University of Texas at Austin. Some of the most common filaments: ABS and PET tend to be brittle so it would not be ideal for a bicycle that experiences many dynamic forces and needs the ductility to flex as well as strength. I settled on Taulman 910 filament which combined the durability/elongation of nylon and the strength of co-polymers.

I printed a couple tubes with Taulman’s 645 Nylon filament which seemed pretty strong and had the ability to bend by hand without cracking. However, I realized that a 3D printed tube is much more expensive than metal, and there might be a better material to do the job. I need look no further than outside my bedroom window where a grove of bamboo plants grew flourishing in the humid hot Houston summer. Bamboo grows so fast and is so strong that it would make a perfect renewable tube for the bicycle. I set to work chopping down some plants and then trying various forms of heat treatment from a blow torch, to the oven. A few burnt ends and one smoky kitchen later, I had (somewhat) dry tubes to work with. For those intending to work with bamboo, I suggest either letting them air dry in a dry place out of the sun or at very low temps in an oven with no part of the bamboo touching the oven sides.

To connect these tubes, I used the Taulman 910 to create modular connector pieces. The pieces were custom printed with receiving holes for the diameter of the bamboo pieces I had cut earlier. The nice thing about 3D printing these parts is that you can conform to the exact geometry of your bicycle dimensions and the tubes you decide on using. Using the Simplify 3D program, I was able to examine my layers to make sure the path of my support structure would work out alright. The connector piece shown here is the bottom bracket where the pedal cranks, down tube, seat tube, and chainstays connect.

Interfacing with the rest of the components was the next challenge. The bicycle wheels clamped onto fork shaped dropouts which were easy enough to print. The real fun was going to be putting the crank arm bearings and the headset on. I decided to try a press fit approach for the crank bearings. The 910 was ductile enough to press those bearing right in there. Nothing to block rotation. In addition, I found out that you can machine 910 prints. The headset nuts have threads on the internal diameter that needed to thread onto the frame. I threw some of my 3D printed tubes on the lathe, turned them down, and added some threads. It worked much better than expected. Just remember to make your wall thickness large enough so that you don’t machine into the infill.

The bamboo tubes, the 3D printed tubes and connector pieces all slid together nicely with only a minor fit problem. I forgot support structure on one of my rear dropouts, thus I heated it in some hot water to make it malleable enough to bend back into the proper shape. Everything was adhered together with a two part epoxy and held in place by my bungee cord fixture.

The end product looks much like a real bicycle and may have had the chance to ride like one. A few technical problems kept this prototype from being fully functional. There was some interference along the chain path to prevent usage of some of the gears. Also, the 3D printed tube that runs through the headset above the front fork failed under the large moment that is created by the front fork acting as a lever arm. The rest of the frame, however, was very strong and was able to support weight.

At the end of my time in Houston, I was very surprised at how far the bicycle was able to come along thanks to the structural properties of the Taulman 910 as well as the large format printing capabilities of the Gigabot. If I were to do it again, I would use as much bamboo as possible so it could be renewable. I would also focus on how little plastic material would be needed to make strong connectors, possibly experimenting with more renewable filaments such as PET despite its limitations. Although it wasn’t completely functional, I am confident that yes, it is possible to create a working 3D printed bicycle. One aspect I did like about the modular design was its ability to conform to the exact dimensions needed. All that would be needed would be to change a couple of angles and bamboo tubes lengths, and you would have the geometry for any human rider. You could have a bicycle custom fit to you without needing to settle on a typical configuration. In addition, I liked how easy it was to put together. Anyone with a 3D printer, a bamboo conducive climate, and a nearby bicycle parts repository (like the Austin Yellow Bike Project) Keep your eyes open as I have seen others who are working on their own 3D printed bicycles as well.

All in all, this project was a large amount of fun and made for an amazing summer with the Gigabot 3D printer!

Happy Printing!

~Patrick Fiedler: Mechanical Engineering Intern

Want to continue the research? Apply for an internship at re3d.org/careers!

Made in America: 3D Printing Prototypes for Stump Armour Molds

Meet Travis: A Texan, father, entrepreneur, warrior, and inventor.

re:3D first met Travis in Austin last winter as he was prototyping his second version of Stump Armour: an affordable, accessible device he pioneered in order to expand mobility options for bilateral amputees.

As a combat-wounded Marine, Travis is uniquely qualified to inspire solutions to increase maneuverability for other double amputees while reducing back strain that traditional prosthetics can create. By using himself as the test subject and leveraging business insights he acquired in the 100 Entrepreneurs Project and the Entrepreneurial Bootcamp for Veterans (EBV), Travis launched Stump Armour on indiegogo this week.

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Stump Armour Mod 1

About Stump Armour

Stump Armour is a round design that connects to traditional sockets to allow for constant surface contact from any angle. Pressure can be directly applied to a terrain without changing position, allowing amputees to roll themselves up independently when preforming activities close to the ground.  Since the round shape can grab from nearly any position, it works great on uneven/irregular surfaces, so the amputee doesn’t need to focus as much concentration on limb placement when compared to other devices.  Travis doesn’t feel Stump Armour is intended to replace full leg or knee prosthetics. Rather, it’s meant to increase functionality with specific tasks.

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Keeping Costs Low

A key tenant of the Stump Armor’s mission is to make devices as affordable as possible worldwide. For this reason, Travis contracted Mike Battaglia & I last January to see if we could 3D print his vision for a Stump Armour’s Modification. Using Simplify3D we were able to generate a raft & support that could easily break off. The completed PLA prototypes printed great and we were excited to give them to Travis, who planned to use the prints to create a mold to scale Stump Armor globally.

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3D printed Stump Armour Mods 3 (left) and Mod 4 (right) cast at SureCast

Prints in hand, Travis partnered with local foundries who guided him through the process of making his own custom mold to cast multiple sets of Stump Armour.  This week we interviewed Travis to learn more about the process he used to create a mold from a print by working with Stevens Art. Below are the steps that he described:

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  • From a 3d printed prototype made on Gigabot, a silicone rubber mold was created.
  • The print was covered in an releasing agent that was then covered in silicone, leaving an inlet for wax to be poured in later.
  • After the silicone cured, a 2 piece plaster shell was made.
  • Once completed, the silicone was carefully cut with a razor along where the plaster shells come together so it would come apart into 2 pieces.
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  • The shells were clamped together and hot wax was then poured into the inlet.
  • When the wax hardened, the wax casting of the original print was removed.
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  • The wax cast was then dipped in a a ceramic slurry and power coat until a hard shell formed.
  • This shell was fired in an oven to harden the cast melt the wax out.
  • Metal was poured in and the ceramic shell was broken off after it cooled.
  • A metal replica of the original 3d print was then ready for finishing!
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Stump Armour Mod 2

Using lost wax casting, Travis was able to do his first production run of Stump Armour, which is now available to other amputees on the Stump Armour indiegogo campaign. You can support Stump Armour’s next production run and Stump Armour donations at: https://www.indiegogo.com/projects/stump-armour#/  until July 1st.

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Want to learn more?
  • Email: info@stumparmour.com
  • Web: http://www.stumparmour.com/
  • YouTube: https://www.youtube.com/channel/UCsObkfi6W6x2B6dpZ89_CGg/videos?sort=dd&view=0&shelf_id=0
  • Facebook: https://www.facebook.com/Greens-Machines-LLC-716439551739895/
  • Google: https://plus.google.com/u/2/b/106145756742784523319/106145756742784523319/posts
  • LinkedIn: https://www.linkedin.com/company/10602419trk=tyah&trkInfo=clickedVertical%3Acompany%2CclickedEntityId%3A10602419%2Cidx%3A2-1-2%2CtarId%3A1464716547152%2Ctas%3Agreens%20machines

April Puzzler Solution Revealed!

Below is the solution to the Monthly Puzzler Chief Hacker presented in our April Newsletter. Want to play? You can sign up to receive our monthly publication by submitting your email address in the sign up at the bottom of re:3D.org. Proposed answers are presented on our forum at: https://re3d.zendesk.com/hc/en-us/community/posts/206262336-April-Puzzler

The Question

The April puzzler is another print quality mystery. Take a look at the below pictures of an oversized auger screw originally designed for an automated pet feeder. On one side of the auger there is a blemish in the print yet from another view the print shows an excellent surface finish. What is causing the poor print quality on one spot only?

The Solution

The winning answer was presented by whosawhatsis who stated both reasons for the problem.

  1. Uneven cooling
  2. Steep overhang with no support

Great job to everyone and keep an eye out for an improved 360 degree cooling feature for the GB3 hot end to give even better printing capabilities!

Happy Printing!

~Matthew Fiedler

  • Twitter: @chief_hacker
  • Email: engineering@re3d.org

Additive Value for Your Subtractive Manufacturing

Below is Gigamachinist's Steve Johnson's first blog on 3D printing for re:3D's Gigabot fabrication shop.

 Additive Value for Your Subtractive Manufacturing

by Steve Johnson

You may be thinking: “Why would a machine shop need a 3d printer?”

Turns out there are a lot of uses! In my case, we needed to make new fixtures to take advantage of the capabilities of our new 4th axis and the full travel of our machine.  When making fixtures, cost is always a main concern, and making a bad fixture can be expensive in terms of both material and man hours.

By using re:3D’s Gigabot 3D printer, we were able to design our fixture in Solidworks, export the model, and print a full size model of the fixture overnight on Gigabot (no time wasted).

This morning, we tapped the holes for our cam clamps, put the printed fixture into the machine, and checked for clearance and travel issues. In the process we found two issues that we corrected in the solid model, and we are now printing the revised test fixture.

Without the benefit of Gigabot, we may have wasted a 4in diameter by 20in long piece of material, as well as hours of labor. Right now, our only cost has been a few dollars worth of plastic.

This experience has been a great opportunity for me to learn Solidworks and I’m looking forward to using Gigabot again to cut costs, create efficiencies, and to have fun in the shop!

~Happy Printing!

steve@re3d.org

Drones & Open Source: Partnering with Local Motors

Below is a re-post of content MicheleAbbate hosted on the Local Motors Blog at: https://localmotors.com/MicheleAbbate/lmdrones-re3d-gigabot/

LMDRONES: re:3D Gigabot 

As part of the LMDRONES projects that you can find on Local Motors, we want to welcome re:3D and their Gigabot 3D printer as they join our LM Drone efforts!

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May 7th was International Drone Day and the Local Motors Teams, from both Vegas and Chandler, paired up with Matthew Fiedler, Co-Founder and Chief Engineer at re:3D, to bring their Gigabot 3D printer to the world’s first drone port, the Eldorado Droneport, in Boulder City, NV.

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The all day event included open tuning, demonstrations, races, and freestyle flying.  Matt Jackson, Alaric Egli, and Alex Palmer of Local Motors brought a variety of different drones to take part  in the event.  Matthew began printing with the re:3D Gigabot as soon as it arrived, showing it’s potential and usability for creating parts, wings, and even a full size Wing FPV.

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Stayed tuned for what’s next with the re:3D Gigabot which just made its successful journey from Nevada to Chandler, AZ at the Local Motors Headquarters!

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Gigabot arrives at Local Motors Phoenix facility after participating in the International Drone day festivities at Aerodrome near Las Vegas, Nevada. Engineers at Local Motors are excited to train on the Gigabot and start running their first prints!

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re:3D Gigabot can now be found at the Local Motors’ headquarters in Chandler AZ!

#Road2Collision Take 2 & a Southeastern Roadtrip to Digital Now!

We still can’t believe that a year has passed since Matthew, Katy & I packed up Gigabot and embarked on an unforgettable adventure to Collision in Las Vegas. The week was a milestone for re:3D.

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Not only were we honored to win PITCH, the same evening at an afterparty we had the chance to share our vision with Local Motors in an elevator (ironic, we know:), which consequently resulted in a tour the next day of the Las Vegas Local Motors Microfactory and several partnership conversations (stay tuned for more details!). We could hardly contain our excitement when the staff allowed us to take the Varrado Electric Drift Trikes out for a spin!

During Collision, we also finalized our acceptance in indie.vc, an inaugural cohort of 8 proudly bootstrapped companies. As the program launch was in San Francisco, just a few days after Collision, we made the real-time decision to continue driving from Las Vegas to Silicon Valley while visiting customers. Safely in San Fran, Matthew flew home while Lara & Morgan joined me & Katy for the indie.vc kickoff, the Bay Area Makerpro Event (thanks to our friends at OATV), and the San Mateo Makerfaire the following weekend. Katy & I then drove quickly back to Houston where I met up with Rebecca & Ernie for 4 days of Cosplay and 3D printing at Comicpolooza.

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It was a crazy season for our team as we collected requests that informed Gigabot Generation 3.0 while actively engaging with the community (which was well overdue!).  We learned a ton and grew a lot internally, while taking in the beauty of natural parks and inspiring Gigabot use cases our customers shared along the way.

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The journey revealed the importance of listening to those outside of our factory, and the value of sharing our experiences with friends & partners who can support our goals. For this reason, we are thrilled to announce a second roadtrip, this time throughout the Southeast United States as we return to Collision, cheer on this year’s winners, and also attend the Digital Now Conference in Orlando. Once again, we’re hoping to squeeze in a few customer visits and parks along the way.  Most importantly, we hope to catch up with new friends & old, and to possibly see you. We’ll be updating the itinerary below as the next two weeks evolve. Please email marketing@re3d.org if you’d like to set up time for coffee, a demo, some soul food or a beer! Also, to anyone looking to hitch a ride post Collision to TX, we’ll have a couple seats available if you don’t mind squeezing in with our large 3D prints!

TX Library Association

  • When: April 19th-22nd
  • Where: Houston, TX
  • More Info: http://www.txla.org/annual-conference
    • (The Austin team is enroute to do setup with Todd now who will remain in Hou with the gang!)
  • Follow Online: #txla16

Digital Now

  • When: April 21-23
  • Where: Orlando FL
    • Samantha Speaks at the Technology Showcase at 4:05pm on 04/21 with a Gigabot demo afterwards
    • A second Gigabot demo will take place at 9:55 on 04/22
  • More Information: https://www.fusionproductions.com/fusionnews/four-extraordinary-association-stories
  • Follow Online: #diginow

Collision

  • When: April 26-28th
  • Where: New Orleans LA
    • Samantha & Matthew exhibit Gigabot live at the START display: April 26 Booth S118
    • Hardware demo time: TBA
    • Matthew & Samantha will also be at the morning jogs and at night summit all week!
  • More information: https://collisionconf.com/
  • Follow online: @collisionHQ, #collisionconf, #road2collision

Forever Humbled,

Samantha, Katy, Matthew and the entire re:3D team

Katy, Sam & Matthew drive from Houston to San Fran demoing Gigabot & visiting customers (and a few national parks)