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24 Jan 13:11

Bits to Atoms: An Overview of Today's 3D Printing Technologies

by Sean Charlesworth

[Norm's note: If Sean's name sounds familiar, it may be because you first met him as the winner our first Inventern competition, in which he and the two other awesome finalists flew out to San Francisco to spend a weekend working on Adam's final build challenge. But we first heard of Sean when he posted photos and videos of his 3D-printed Octopod vehicle project that was his Masters Thesis at NYU. As it turns out, Sean's expertise is in 3D modeling and printing, and has had experience using various 3D printing technologies and combining rapid prototyping with real-world hardware. Basically, he's way more knowledgeable than us when it comes to 3D modeling and printing. So I was delighted when Sean agreed to share that knowledge with us and Tested readers. Over the course of this year, Sean will be writing a bi-weekly column on Tested about modern home and professional 3D printing technologies, provide tips on how to get started, and share walkthroughs of his various 3D printing projects. To kick things off, Sean's first column is a re-introduction to current state of 3D printers.]

Many of you are probably somewhat familiar with 3D printing. Will’s weekly MakerBot Mystery Builds, CES coverage of new printers, and other highlights pop up all the time, but now we are looking to delve deeper into how these new technologies work and are related to each other. For this first column, I want to start fresh with an overview of the 3D printing process and current methods of printing.

Today's 3D printing is primarily an additive manufacturing technique in which a digital model is translated into a physical object by a machine which ‘draws’ very thin layers of material on top of each other until the object is complete. There is a wide range of machines that print in different ways and materials, including plastic, metal, ceramic, plaster and even rubber.

Up until recently, 3D printing was more commonly referred to as rapid prototyping and/or additive manufacturing. Developed in the 1980’s, it was primarily used in manufacturing industries as a cheaper and faster way to build prototypes. This technology finally reached the consumer-level in the mid-2000’s, mainly due to the hard work of open-source hobby groups such as The RepRap Project. The goal of the Project was to develop and promote an open-source, self-replicating 3D printer and there are many printers based off the RepRap Project. If you buy a kit to assemble, chances are it’s some form of RepRap, in fact MakerBot grew out of the RepRap community. If you want to learn a lot about home 3D printers and possibly build one yourself, this is a great place to start.

The digital model is typically created in either CAD (computer aided design) which is generally used when mechanical parts and precision are needed or a polygon modeler which are typically used for animation and game assets. Examples of CAD programs are AutoCAD, SolidWorks and 123D Design. Some popular polygon modelers are Maya, 3ds Max and Blender. There are advantages and disadvantages to each and many more options which will be covered down the road. The model can even be created by scanning a real object, but regardless of how it’s done, the model is eventually exported as an STL (standard tessellation language) file which simply describes the surface geometry of the model in triangles. The STL should always be processed through a mesh repair program such as netfabb since during construction it is very easy to create a mesh that won’t print properly due to defects in the mesh. Once again, we will talk about this more later.

Once repaired, the STL file has to be ‘sliced’ into the layers that will be drawn by the printer, one at a time, layer-by-layer on top of each other until the object is completed. The STL is brought into a slicing program where you specify how thick each layer should be (resolution, typically in microns), what type of material is to be used, how solid the finished piece should be (solid, hollow, or in-between), how fast it should print and whether support material is to be used. This all varies based on type and brand of the printer and what software is being used. Really big or complicated models can take a long time to slice, particularly on home printers. The slices are turned into gcode, a machine language used for manufacturing on both CNC machines and 3D printers and describes the tool path for printing.

There are a lot of different 3D printing machines out there ranging from kits to mid-priced prosumer home machines, to crazy-expensive industrial machines. I would say that resolution and support material are the two biggest factors dividing printers. Some may argue materials as well but ABS parts that I have printed on my MakerBot are more flexible, stronger and have better longevity than some parts I have printed on the $500,000+ Objet machine. The difference is the Objet can do much higher resolution and support material that allows you to print parts you cannot on a home printer.

For example, let’s say you want to print out a miniature table. If you print it right-side up on a home printer, it will start with the bottom of each leg, build it’s way up to the tabletop and then run into a problem since there is nothing to print the tabletop on. It’s trying to print in empty space and the print will most likely fail. The high-end machine will have some type of support material that it will build up under the tabletop so there is something to print on. The support material is removed once the print is complete.

Now in this case the best thing to do is simply flip the table upside down so it prints the tabletop first and then the legs. This orientation needs no support so it will print fine on the prosumer and save money on the high-end printer. Prosumer printers do have support material made by either printing extra structures to hold up overhangs or using dissolvable materials. Up until recently I would never use support on my home printer since it never worked very well and would put blemishes on the model surface. For dissolvable material you need a machine with dual print heads and relatively mild chemicals to dissolve it. Great improvements have been made on support generation on prosumer printers and I use them more often as of late.

About 3 hours later, the print is done and ready to clean.

Now that we have covered how it all works, let’s take a look at the different 3D printing technologies in use today. This is terminology I'll be referring to in future columns, and that acronyms you may read or hear in 3D printing coverage.

Printed using FFF.

FDM - Fused Deposition Modeling

Thermoplastic filament off a spool is heated and extruded through a nozzle and ‘drawn’ onto a print bed. Most home machines are FDM or technically…

FFF - Fused Filament Fabrication

This is the exact same thing as FDM but can’t be called that due to trademarks. MakerBot, Ultimaker, Cube, Solidoodle, are all FFF machines. Most print with PLA (biofilament made with corn or organics, smells like waffles) or ABS (LEGO plastic).

FFF tends to be the affordable printers with very affordable materials. Prints can go up to pretty high resolution and can be very strong. Resolution still can’t match SLA and other high-end printing and supports can be messy to remove and not as effective as other machines.

3DP - Three-Dimensional Printing

The term for original ZCorp machines which uses a plaster-like powder and a cyanoacrylate (super glue) binder. This type of printer has a print chamber which starts in the up position, a thin layer of plaster powder is laid down and an inkjet head distributes the binder material anywhere the model should be on the print bed. The platform moves down and another layer of powder is distributed and bound. The interesting thing about this method is any powder which is not part of the model acts as the support material. If the model is designed to be hollow, significant savings can be had since any loose support powder can be reclaimed and reused. This is also the only printer that can do full-color, this is what Shapeways uses for Sad Keanu, etc.

Printed using 3DP.

3DP is usually the cheapest pro option, does detail pretty well, but not as good as SLA or SLS but can do full color prints. Finished models are very fragile until they are infiltrated which requires them to be completely dipped in super glue. After infiltration they feel like and have the strength of unfinished ceramic.

CJP - ColorJet Printing

This is what 3DP is now called since 3D Systems bought ZCorp. It’s the same thing, although they have announced a plastics-based machine which can also do full color.

Photo credit: 3D Systems

SLA - Stereolithography

The first type of 3D printing developed in the 1980’s by 3D Systems. Uses a laser which ‘draws’ each layer in a vat of liquid resin. Wherever the laser hits the resin it hardens and forms a layer. The object is anchored to a platform which moves in or out of the vat (depending on the printer) as layers are added. Supports are typically small ‘spears’ that can be easily broken off after printing. Some machines require additional UV curing of the model after removal from the vat.

SLA can be very strong and very high resolution but removing all of the support spears can be a giant pain and cause surface blemishes. Most SLA machines are professional versions except for the Form 1 which is a great prosumer machine developed by MIT grads.

SLS - Selective Laser Sintering

The setup is similar to 3DP but uses a laser to fuse a thin layer of plastic, glass, ceramic or metal and loose material still acts as support. Plastics models are ready right out of the printer. Ceramic, metal and glass may need to be fired to further fuse the particles together.

SLS is nice since the support is easy to clean up and most models are ready right out of the printer. Surface finish is still slightly rough like 3DP but can be polished. Details are usually very good and slightly better than 3DP. Plastics are very strong and slightly flexible. This is Shapeways goto tech for most of their prints including the great Strong & Flexible material.

DMS - Direct Metal Sintering

Similar to SLS but directly binds and melts metal powder together for structurally sound and pure parts. I believe this is what NASA was using to make jet nozzles.

Image Credit: Morris Technologies

PolyJet

Composite liquids are drawn on print bed with inkjet heads then cured with UV light. Not as messy as most of the other methods but uses a wax-like support material that encases parts that need it. Objet machines were unique in printing multiple materials by using two print cartridges. An Objet Connex 500 can print rubber and plastic at the same time. Or different digital mixes or color and/or hardness at the same time. This is how I made the rubber tentacles for my Octopod and printed rivets and other details right out of the printer.

Polyjet is capable of high resolution, a wide range of materials including rubber and can print overmolds (plastic with rubber modeled to it like your toothbrush). The support material can be a pain to remove, usually starting with a water jet and moving to using mild lye baths, but the end result looks great. Some of the materials do not hold up well over time, but it’s mainly meant for prototypes.

MJP - MultiJet Printing

3D Systems just announced their version of Polyjet which can do the same type of stuff as the Objet. I believe that 3D Systems uses a wax support that melt away when heated. Don’t have any experience with this stuff yet.

Paper

Mcor Technologies uses reams of paper which are laser cut and glued together to make objects. The resolution is dependant on the thickness of paper and full color prints can be done by first printing out each paper layer on a regular printer. Staples is supposed to be offering print services with these in house. I’m skeptical as to how well this will do, although I have seen some prints in person and they were not bad for being paper.

Food

3D Systems has announced the ChefJet which will print in sugar and chocolate. It uses technology similar to 3DP (CJP) and can even do full color in sugar. It lays down a thin layer of ultrafine sugar and binds it with water. For chocolate it lays down a milk/cocoa powder layer and adds cocoa butter to bind it. Pretty cool, but how does it taste? Was Will just being polite?

Hope you enjoyed this overview, we’ll continue to tackle different topics and do some walkthroughs of 3D printing projects over the next few months. And if you have questions about specific 3D printing topics or technologies, please post them in the comments below!

Photos courtesy Sean Charlesworth unless indicated.

23 Jan 16:15

Yes, There Is A Yuengling Ice Cream; But No, It Will Not Give You A Boozy Buzz

by Mary Beth Quirk

yuenglingicecreamIf you’re the type of person who’s tried (or is willing to try) mixing beer and ice cream in some kind of alcoholic, creamy float dessert, hearing that there’s a brand of Yuengling ice cream that’s just now returning to shelves might sound like a dream come true. And while it’s true, all right, there’s no actual beer involved in the dessert.

It’s been almost 30 years since the last carton of Yuengling’s Classic Ice Cream disappeared from the grocery store shelf, so it’s no wonder devoted fans are in a bit of a tizzy, as noted by Foodbeast.

D.G. Yuengling & Son was founded in 1829 and is now the oldest brewing company still in operation here, although the ice cream arm is completely — and unfortunately, for many — separate from the beer side of things.

When Prohibition hit in the 1920s, the brewery decided to turn its talents to other industries, including the dessert set. The owner of the brewery started Yuengling’s Ice Cream Corporation in 1920 in Pottsville, Penn. to deal with the moratorium on booze set by the 18th Amendment, the company site explains.

And from there on, the ice cream became a fan favorite, even after Prohibition was repealed in 1933. That ended in 1985 when the family decided to close up the factory and donate the building.

But as of last week, Yuengling’s Ice Cream is back in production under the ownership of one of the Yuengling family, and will make its return to shelves by mid-February of this year at certain East Coast stores. As for that beer float, the closest brewed flavor is probably Root Beer Float. But if you want actual Yuengling, well, you’ll have to add that yourself.

(Oh and in case you’ve never encountered Yuengling in any of its forms and are curious about the pronunciation: It’s “ying-ling.”)

23 Jan 16:12

Better, Stronger, Faster? New Federal Safety Rules Proposed for Child Car Seats

by Kate Cox

From a parent’s perspective, frequent changes in car seat regulations and standards can be daunting. Still, safety is paramount, and so the National Highway Traffic Safety Administration (NHTSA) is proposing a round of new safety standards for child car seats.

The changes would add side-impact crashes to the battery of tests that child safety seats currently undergo. The proposed new test would simulate a T-bone style crash: the striking vehicle, moving at 30 mph, strikes a smaller passenger vehicle moving at 15 mph. The specially designed sled test also simulates the vehicle door crushing inward, toward the car seat.

The new test will not only use the exiting crash test dummy that represents a one-year-old baby, but also a new crash test dummy that represents a three-year-old toddler. It will cover car seats used for children up to 40 pounds.

Testing car seats for safety in side-impact crashes was first suggested as far back as 2003; much of the intervening decade was spent researching what, very specifically, to test for. The NHTSA has proposed a three-year window for car seat manufacturers to make any needed changes to their designs when the rule becomes final.

The NHTSA is also revising its policy on the LATCH system for installing car seats, USA Today reports. LATCH was designed to make car seat installation easier for parents (although it’s not always as seamless as intended). The new rule, expected to go into effect in February or March, indicates that LATCH should not be used for a combination of car seat and kid weighing more than 65 pounds.

Car seat manufacturers will have to label their seats to indicate at what weight point parents should swap over to using a seat belt attachment instead. So for example, a seat that weighs 30 pounds would have to indicate that for use with children over 35 pounds, the seat should be hooked into the seat belt.

Seat weights are not currently generally labeled. When they are, many parents may find it hard to believe that the seat does not actually weigh a hundred pounds; it only feels like it on the interminable walk to the front door.

New regulations sought for child car seats [USA Today]

23 Jan 16:11

Craigslist “Emergency” Taco Bell Delivery Request During Snowstorm Ends With A Full Stomach

by Mary Beth Quirk

When there is booze involved, there are many situations you may find yourself in that you normally would not get into. Say, there’s a certain cuisine you only crave when drinking. But what happens if a snowstorm foils your tipsy plans? Turn to the Internet, like one Baltimore Craigslister did yesterday in his quest for Taco Bell.

The newest darling of the Internet for the next 15 minutes or so emerged yesterday, in the form of a guy asking someone with sufficient wheels to handle the whirling snow. He wrote (with some tidying of expletives):

“Guys it’s snowing like a bitch outside, I’ve had a few drinks too many, and my sh***y little hybrid douchemobile can’t possibly make it to the neighborhood Taco Bell in this weather,” he explained. “I need someone with a 4 wheel drive vehicle to come pick my drunk ass up, take me to the Taco Bell drive-thru, and drive me back home.”

He goes on to offer a fun time playing video games if the person isn’t a total creeper, and offers payment in tacos, chalupas or “whatever.”

“Seriously my desire for tacos right now is totally unmanageable, so I’d probably even buy you a 7 layer burrito if you asked nicely.”

The end of the story is provided over on Reddit, of course, where a post on his Craiglist ad came full-circle. The Craigslist poster joined the comments to let everyone know that he eventually sobered up and went on the Taco Bell mission himself.

“I am currently nursing my taco baby,” he wrote on the Reddit post.

However, he did get 25-30 replies by the time he decided to serve himself and thought the better of having a crusading stranger save him from his food quandary. All’s well that ends well, right?

23 Jan 16:10

Truck Spills Massive Amount Of Beer On Same Ramp That Was Covered In Chicken A Week Ago

by Chris Morran

(WSBTV)

(WSBTV)

You may remember last week, when a truck overturned outside of Atlanta and spilled some 40,000 pounds of frozen chicken on the road. This morning, that same highway ramp was doused in beer after a very similar incident.

WSBTV reports that the incident occurred around 2 a.m. on the ramp connecting I-285 and I-20 in DeKalb County, GA.

The overturned truck spilled pallets of Bud Light all over the road, closing down the ramp for several hours. No one appears to have been hurt, though we imagine the unfortunate clean-up crew that had to sweep up all that busted beer will likely carry around that smell for the rest of the day.

According to the Atlanta Journal Constitution, this is the exact same ramp that was the site of last week’s chicken spill.

At this rate, we’re predicting a third truck loaded with some sort of snack will overturn on this ramp, completing the party food trifecta. We’re not superstitious, but if we were hauling pallets of any of the following — frozen pizza, soda, mixed nuts, chips, or any sort of dip — we’d probably avoid this particular ramp for the time being.

23 Jan 16:06

Secret Service visits FL candidate who called for president's hanging

Local politician Joshua Black's call for the hanging of President Barack Obama got him a visit from
23 Jan 15:46

Streamlight TLR-1s - $98.74 shipped

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23 Jan 15:45

KIMBER SOLO CARRY 9mm 2.7" Barrel 6 Rnd MICRO-COMPACT - $599.99

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23 Jan 15:45

Glock 41 Gen 4 Pistol .45 ACP 5.45in 13rd Black - $640 + $5.99 S/H

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23 Jan 15:45

Glock G42 .380 ACP 3.26" barrel 6 Rnds - $449 + Free Shipping

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23 Jan 15:44

Century Arms ZASTAVA NPAP 16.25" 7.62X39 BLK SYN 30RD - $466.67 shipped after coupon

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RUGER 10/22 22LR CAMO TACSTAR TACTICAL TALO - $339.67 shipped

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GLOCK G42 380ACP 6RD 3.25 FS BLK - $428.31 + $5.99 S/H

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23 Jan 15:44

Yugo Zastava PAP M85PV AK Style Pistol Krink pattern, in 5.56mm (223), with PACKAGE DEAL of 35 Magazines! - $599.95

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23 Jan 15:43

Mossberg 464 SPX Lever 30-30 16.25" Blue 6 Position Flash Hider Fiber Optic 41026 - $381.07

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23 Jan 15:43

Yugo M70 AK Type Semi - Auto Lo Cap N-PAP Rifle Plus 12 Additional Ten Round Mags - $449.99

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23 Jan 15:42

Keltec PF-9 Limited Edition 9mm in Billfold Brown #KELTEC-PF-9 - $229.99

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23 Jan 15:18

ASUS VivoTab RT 32GB 10.1" Tablet + ASUS Mobile Dock $230 at eBay

Ends 2/8 at 8AM PT. eBay with voodublu has the refurbished ASUS VivoTab RT TF600T-B1-GR 32GB 10.1" Tablet (Gray) for $230 with free shipping. Weighs 1.16 lbs and features Windows 8 RT installed.

Includes Asus VivoTab Keyboard Docking Station with purchase.

  • NVIDIA Tegra 3 1.3GHz Quad-core, 2GB DDR3, 32GB storage
  • 10.1" 1366 x 768, front/rear cameras, BT 4.0, 802.11 b/g/n
  • 23 Jan 14:40

    Quirky bunny on Mandela statue causes stir

    (AP) A new, 9-meter (29.5-foot) sculpture of Nelson Mandela is billed as the biggest statue of th
    23 Jan 13:50

    Google Chrome Has a Bug That Lets Any Site Eavesdrop On You

    by Eric Limer
    Wmy2k7

    INTERESTING VIDEO!!!!

    Voice control is an awesomely futuristic way to control your technology like a spaceman, but only if you can trust it. So you might want to stay tight-lipped around Chrome; Google's browser has a dangerous security flaw that can let malicious sites eavesdrop on your every word.

    Read more...


        






    23 Jan 13:47

    Shocking Photos from the Water Sports Site of the Rio Olympics

    by Attila Nagy

    Shocking Photos from the Water Sports Site of the Rio Olympics

    Getty Images has published a fresh set of photos from the heavily polluted Guanabara Bay in Rio de Janeiro—which is the site chosen for water sports at the Rio 2016 Summer Olympics. The photos are frankly shocking, as the iconic bay will be the site of sailing events during the summer Olympic Games.

    Read more...


        






    23 Jan 13:47

    Virgin Galactic Doesn't Have FAA Permission to Fly You to Space

    by Robert Sorokanich

    Virgin Galactic Doesn't Have FAA Permission to Fly You to Space

    If you're one of the 700 or so people who bought tickets to fly to outer space on Richard Branson's Virgin Galactic rockets, don't pack your space bags just yet: Smithsonian notes that the company doesn't have the Federal Aviation Administration permit required to take passengers to space. Hope you folks got traveler's insurance. Or kept your Bitcoin receipts. [Smithsonian]

    Read more...


        






    23 Jan 13:17

    New video footage of world's tallest waterslide is absolute insanity

    by Greg Newkirk on Roadtrippers, shared by Brian Barrett to Gizmodo

    You might have heard the rumors that Kansas City is about the receive the world's largest waterslide, but if you haven't seen the new drone-shot video.. you don't know how terrifying it's actually going to be.

    Read more...


        
    23 Jan 13:15

    A Single Man Spent 53 Years Building This Massive Cathedral

    by Kelsey Campbell-Dollaghan

    A Single Man Spent 53 Years Building This Massive Cathedral

    Very few of us will work at a single job our whole lives. Even fewer will work on a single, self-led project our whole lives. Spanish octogenarian Justo Gallego Martinez is an exception: He's been the sole designer, engineer, and construction worker on a cathedral in Madrid since 1961.

    Read more...


        






    23 Jan 13:09

    An abandoned veterinary school looks like the most terrifying place

    by Casey Chan on Sploid, shared by Casey Chan to Gizmodo

    An abandoned veterinary school looks like the most terrifying place

    Old mental institutions. Haunted houses. Cemeteries at night. Clown conventions. They're all terrifying. But I'm pretty sure I'd rather sleep overnight in those places than spend a single minute in this abandoned veterinary school. At this horrifying school you see animal heads trapped in formaldehyde, organs floating around, death surrounding you and monsters in the hallways (presumably).

    Read more...


        
    23 Jan 13:09

    Cute animation explains everything you need to know about NFL football

    by Casey Chan on Sploid, shared by Casey Chan to Gizmodo

    Because we are in the US, I'm not going to call football "American Football" or whatever other people call our version of not-soccer outside of the USA. It's football here. That's the end of it. But I get it. To people who know football as some other thing or don't care to know our football as anything, the sport doesn't seem to make any damn sense. It's okay. It's as silly as America itself.

    Read more...


        
    23 Jan 13:06

    Waiting in line looks way cooler when five Hercules aircraft do it

    by Casey Chan on Sploid, shared by Casey Chan to Gizmodo

    Waiting in line looks way cooler when five Hercules aircraft do it

    Like ducks in a row, five C-130 Hercules aircraft lined up before taking off at Yokota Air Base, Japan. That's one intimidating traffic jam to be in. The picture was taken for the US Air Force by Senior Airman Cody H. Ramirez on their Instagram page.

    Read more...


        
    23 Jan 13:05

    This Is What Happened When Google Raced Top Gear in a Street View Car

    by Jamie Condliffe

    Street View cars may be packed with technology, but how do they do on a race track? This video shows what happened when the guys at Google decided to go race the folks at Top Gear.

    Read more...


        






    22 Jan 17:12

    44 Reasons Why Evolution Is Just A Fairy Tale For Adults

    by Michael Snyder
    Wmy2k7

    interesting read

    The theory of evolution is false.  It is simply not true.  Actually, it is just a fairy tale for adults based on ancient pagan religious philosophy that hundreds of millions of people around the world choose to believe with blind … Continue reading →

    The post 44 Reasons Why Evolution Is Just A Fairy Tale For Adults appeared first on .

    22 Jan 16:42

    Why I Cannot Support Concealed Carry Weapons Permits (And Why You Shouldn’t Either!)

    by Mac Slavo
    Wmy2k7

    I didn't think the fact that you have a CWP showed up if they run your tag.....

    John Filippidis is a Concealed and Carry Weapons permit holder, which means he can carry his firearm on his person or in his car legally. He followed all applicable laws in the State of Florida to obtain his permit, and … Continue reading →

    The post Why I Cannot Support Concealed Carry Weapons Permits (And Why You Shouldn’t Either!) appeared first on .