What does it take to make a really big digital clock? If [Ivan Miranda]’s creation is any gauge, it takes a really big 3D printer, an armful of Neopixel strips, and a ton of hot melt glue.
It looks like [Ivan]’s plus-size clock is mainly an exercise for his recently completed large-bed custom 3D printer, in itself a project worth checking out. But it’s a pretty ambitious project, and one that has some possibilities for enhancements. Each of the four seven-segment displays was printed separately, with a black background, translucent white for the segments, and recesses for five RGB LEDs each. The four digits and colon spacer are mated together into one display, and an ESP8266 fetches the time from a NIST server and drives the segments. What’s really interesting about [Ivan]’s projects is that he constrains himself to finishing them each in a week. That explains the copious amount of hot glue he uses, and leaves room for improvements. We’d love to see this display built into a nice walnut case with a giant red diffusing lens. Even as it stands it certainly makes a statement.
Thankfully it’s rare that we report on something as tragic as the death of a 17-year old, but the fact that the proximate cause was a 3D printer makes it all the worse and important for us to discuss.
The BBC report tells of a recently concluded coroner’s inquest into the December death of a young man in a fire at his family’s magic shop in Lincolnshire. The building was gutted by the fire, and the victim died of smoke inhalation. The inquest found that he had been working with a 3D printer in the shop and using hairspray to prepare the bed, a tip he apparently picked up from forums and blogs.
Unfortunately for this young man and his family, the online material didn’t mention that hairspray propellant contains volatile hydrocarbons like propane, cyclopropane, n-butane and isobutane — all highly flammable. Apparently the victim used enough hairspray in a small enough space to create an explosive mixture of fuel and air. Neighbors reported a gigantic fireball that consumed the shop, which took 50 firefighters to control.
While the inquest doesn’t directly blame the 3D printer as the source of ignition — which could just as easily have been a spark from a light switch, or a pilot light on a water heater — it does mention that the hot end can reach 300C. And the fact remains that were it not for the 3D printer and the online tips, it’s unlikely that a 17-year old boy would be using enough hairspray in an enclosed space to create what amounted to a bomb.
By all accounts, the victim was a bright and thoughtful kid, and for this to have happened is an unmitigated tragedy for his family and friends. This young man probably had a bright future and stood to contribute to the hacker community but for a brief lapse of judgment. Before anyone starts slinging around the blame in the comments section, think about it — how many time haves you done something like this and gotten away with it? This kid got badly unlucky and paid the ultimate price. Maybe we should make his death worth something by looking at what we do that skates a little too close to the thin edge of the ice.
With proper tuning, any 3D printer can create exceptionally detailed physical replicas of digital files. The time it takes for a printer to print an object at very high detail is another matter entirely. The lower the layer height, the more layers must be printed, and the longer a print takes to print.
Thanks to [Steve Kranz] at Autodesk’s Integrated Additive Manufacturing Team, there’s now a solution to the problem of very long, very high-quality prints. It’s called VariSlice, and it slices 3D in a way that’s only high quality where it needs to be.
The basic idea behind VariSlice is to print vertical walls at a maximum layer height, while very shallow angles – the top of a sphere, for example – are printed at a very low layer height. That’s simple and obvious; you will never need to print a vertical wall at ten micron resolution, and fine details will always look terrible with a high layer height.
The trick, as in everything with 3D printing, is the implementation. In the Instructable for VariSlice, it appears that the algorithm considers the entire layer of an object at a time, taking the maximum slope over the entire perimeter and refining the layer height if it’s necessary. There’s no weird stair stepping, overlapping layers of different thicknesses, or interleaving here. It’s doing automatically what you’d normally have to do manually.
Nevertheless, the VariSlice algorithm is now one of Autodesk’s open source efforts, just like the Ember resin printer used in the example below. The application for this algorithm in filament-based printers is obvious, though. The speed increase for the same level of quality is variable, but the time it takes to print some very specific objects can be up to ten times faster. Whether or not this algorithm can be integrated into Cura or Slic3r is another matter entirely, but we can only hope so.
When it comes to 3D printers, most machines you’ll see are pretty small. The Ultimaker, Prusa, Lulzbot, and the Rostock Max are desktop devices. While they have entirely usable build volumes, you’re not printing furniture with these machines. Yes, large format 3D printers exist, like the SeeMeCNC Part Daddy (they’ll build you one for ~$90,000, IIRC), a house printer that uses concrete, and a number of very large printers from various other manufacturers with very high price tags.
There is no 3D printer designed to print large objects without spending tens of thousands of dollars on a machine. That’s the focus of this Hackaday Prize entry. [RigTig]’s Big 3D Printer is designed to be big, but also inexpensive.
A big, inexpensive 3D printer can’t use the usual machine setups seen in other large format printers. Big machines with traditional kinematics demand big pieces of aluminum, counterweights, and a design that might spiral out of control. Instead of a thousand pounds of metal, [RigTig] is using something like the Skycam system seen at every NFL game; put a few towers up at the corners of a triangle, run some string or cable through some pulleys, and you have a simple, light movement platform.
With the machine side of the problem figured out, the next question is what material to use. [RigTig] has decided plastic filament is impractical because of cost. A clay extrusion system has a lot of problems. Concrete is a good idea, but the prints would weigh several tons. Right now, [RigTig] is planning on using dirt with a polymer binder. It’s an interesting idea, and one we haven’t seen elsewhere.
Building a 3D printer from scratch is easy. Building a huge 3D printer is one of the most interesting engineering challenges out there. Not only do you need a motion platform that can make it work, but you also need to print in a material that is cheap enough and prints fast enough for the printer to make sense. We don’t know if [RigTig] is on the right track yet, but we’re glad to see him put in the effort for this excellent addition to the Hackaday Prize.
[Tallaustin] worked at Stratasys as an intern this past summer. They let him know that he was welcome to use their fancy industrial printers as much as he’d like. Not to waste such an opportunity he promptly got to work and designed an electric longboard, printable for a mere $8,000.
[Tallaustin] is presumably tall, and confided to Reddit that he weighs in at 210 lbs. For those of us who have had the pleasure of designing for FDM 3D printing, we know that getting a skateboard one can actually skate on without it delaminating somewhere unexpected is pretty difficult if you weigh 80 lbs, 200+ is another category entirely. So it’s not surprising that his first version shattered within in moments of testing.
So, he went back to the drawing board. Since he had his pick of all of Stratasys’s most expensive and fine spools of plastic, he picked one of the expensivest and finest, Ultem 1010. Aside from adding a lot of ribbing and plastic, he also gave it a full rundown with some of SolidWorks’s simulation tools to see if there were any obvious weak points.
Six days of exceedingly expensive printing later, he had a working long board. The base holds some batteries, an ESC, and a 2.4 GHz transceiver. The back has a brushless motor that drives a pulley slotted into one of the wheels. The rest is standard skateboard hardware.
If you’d like to build it yourself he’s posted the design on Thingiverse. He was even nice enough to put together a version that’s printable on a plebeian printer, for a hundredth of the price.
If you have a 3D printer, your nozzle and heater block are invariably covered in a weird goo consisting of decomposed and burnt plastic. There’s only one way around this – a nozzle sock, or a silicone boot that wraps around the heater block and stops all that goo from accumulating.
Right now, E3D sells silicone nozzle socks for their normal-sized heater blocks, with a release for their maxi-sized Volcano blocks coming shortly. [Ubermeisters] couldn’t wait, so he designed a 3D printed mold to cast as many Volcano nozzle socks as he could ever need.
The mold itself is taken from the mechanical drawings of the E3D Volcano hotend, printed in Proto Pasta HTPLA. To create the nozzle sock, this mold is filled with a goo made from GE Silicone I, mineral spirits, plaster of Paris, carbon powder, aluminum powder, titanium microspheres, and bronze powder colorant from Alumalite.
The mold is sprayed with release, filled with silicone goo, and slowly brought together. After a few hours, the silicone has cured, can be removed from the mold, and the flash can be cut away from the finished part. The end result is great — it fits the Volcano hotend well, and shouldn’t be covered in melted, burnt plastic in a week’s time.
All the files for the Volcano nozzle sock mold can be found on YouMagine. Alternatively, you could wait another month or two for E3D to release their ‘official’ Volcano nozzle sock.
Building a big 3D printer has its own challenges. The strength of materials does not scale linearly, of course, and long axes have a tendency to wobble. That said, building a bigbot isn’t hard – stepper motors and aluminum extrusion are made for industry, and you can always get a larger beam or a more powerful motor. [James] is going in the opposite direction. He’s building tiny, half-scale printers. They’re small, they’re adorable, and they have design challenges all their own.
At this year’s New York Maker Faire, [James] is showing off his continuing project of building baby 3D printers. He has a half-scale wooden Printrbot, a half-ish scale Mendel Max, a tiny Makerbot Replicator, and a baby delta and baby Ultimaker in the works.
Click past the break for a gallery, and more info on [James’s] tiny creations.