3d Printer hacks

2714 Articles

3D Printer Tragedy Claims A Life

November 3, 2016 by 136 Comments

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.

Continue reading “3D Printer Tragedy Claims A Life” →

Variable Thickness Slicing For 3D Printers

November 3, 2016 by 25 Comments

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.

Continue reading “Variable Thickness Slicing For 3D Printers” →

Mastering Ball Screws

November 2, 2016 by 32 Comments

Most inexpensive 3D printers use a type of lead screw to move some part of the printer in the vertical direction. A motor turns a threaded rod and that causes a nut to go up or down. The printer part rides on the nut. This works well, but it is slower than other drive mechanisms (which is why you don’t often see them on the horizontal parts of a printer). Some cheap printers use common threaded rod, which is convenient, but prone to bad behavior since the rods are not always straight, the threads are subject to backlash, and the tolerances are not always the best.

More sophisticated printers use ACME threaded rod or trapezoidal threaded rods. These are made for this type of service and have thread designs that minimize things like backlash. They typically are made to more exacting standards, too. Making the nut softer than the rod (for example, brass or Delrin) is another common optimization.

However, when lead screws aren’t good enough, mechanical designers turn to ball screws. In principle, these are very similar to lead screws but instead of a nut, there is a race containing ball bearings that moves up and down the screw. The ball bearings lead to less friction.

Misumi recently posted a few blog articles about ball screws. Some of the information is basic, but it also covers preloading and friction. Plus they are promising future articles to expand on the topic. If you prefer to watch a video, you might enjoy the one below.

Continue reading “Mastering Ball Screws” →

The Potowitzer: A Rapid Fire Potato Cannon

October 31, 2016 by 38 Comments

If you’ve ever fired a potato cannon, you’ll know that they are a raucous good time, but are somewhat clumsy to reload after each shot. Seeing an opportunity to improve on the design and minimize the delay between launches, [Danger First] have concocted a fast reloading potato cannon — or should I say — Potowitzer.

The key here is that they’ve gone through the extra effort of designing and building honest-to-goodness artillery rounds for their Potowitzer’s manual breech-loading mechanism. Foregoing the inconsistency of potatoes, they’ve 3D printed a bevy of bullets and sealed them with propane gas into PVC pipe cartridges. Metal contacts around the base to carry current from a BBQ lighter to the inside of the cartridge to ignite the propellant. Seeing it fire at about 18 rounds per minute is something special.

Continue reading “The Potowitzer: A Rapid Fire Potato Cannon” →

Minecraft Sword Lights Up When Nearby Friends

October 21, 2016 by 8 Comments

With All Hallow’s Eve looming close, makers have the potential to create some amazing costumes we’ll remember for the rest of the year. If you’re a fan of the hugely addict-*cough* popular game Minecraft, perhaps you’ve considered cosplaying as your favorite character skin, but lacked the appropriate props. [Graham Kitteridge] and his friends have decided to pay homage to the game by making their own light-up Minecraft swords.

These swords use 3D-printed and laser-cut parts, designed so as to hide the electronics for the lights and range finder in the hilt. Range finder? Oh, yes, the sword uses an Arduino Uno-based board to support NewPixels LEDs and a 433Mhz radio transmitter and receiver for ranged detection of other nearby swords that — when they are detected — will trigger the sword to glow. Kind of like the sword Sting, but for friendlies. Continue reading “Minecraft Sword Lights Up When Nearby Friends” →

Hackaday Prize Entry: Antigravity Arm Floaties

October 20, 2016 by 19 Comments

A few years ago, [Mike] heard about orthotic devices for people in wheelchairs that make it easier to them to move their arms. His daughter had the opportunity to demo one of these devices, and the results with the device were good. The fights with the insurance company were not so good, but this really was a device that could be made on a 3D printer with a few rubber bands, after all. Thus, [Mike] invented 3D printed antigravity arm floaties.

The name basically tells the story — these antigravity arm floaties work well to counter the pull of gravity for individuals with low muscle tone. [Mike]’s daughter found the professional, official, not-covered-by-insurance version useful, so [Mike] decided to build his own. There’s really not much to it – it’s just a few 3D printed parts attached to a wheelchair with a few rubber bands giving the mechanical linkages some resistance.

In the true hacker spirit, [Mike] took the basic idea of these spring-loaded arm floaties and put a new twist on it. He’s using a chain as the mechanism that allows freedom of movement in the XY plane. This makes the device slightly better, and is by every account an improvement on the commercial version. That’s what you get when you can iterate quickly with a 3D printer, making this project an excellent example of what we’re looking for in the Assistive Technology portion of the Hackaday Prize.

The HackadayPrize2016 is Sponsored by:

Hackaday Prize Entry: 3D Prints For The Visually Impaired

October 19, 2016 by 7 Comments

Students with visual impairments can have difficulty with visual and spatial relationships. 3D printers can print almost everything, and with a lot of CAD work, this project in the Hackaday Prize provides these students with physical objects to learn any subject.

[Joan] and [Whosawhatsis] have already written the book on 3D printed science projects and have produced a 3D printed Braille map of a campus, but for this project, they’re making things a little bit simpler. Visually impaired students are tactile learners and the simplest of their 3D printable objects are fixed volume objects. This collection of 3D printable cylinders, cones, prisms, and pyramids give a physical representation of geometric solids. These objects also have another trick up their sleeve: they all contain the same volume. Fill the cylinder up with water, pour that water into a cone, and the student will discover that they all contain the same volume.  That’s useful for the visually impaired, but would also put these printable shapes at home in any elementary or middle school math class.

This project already has a rather large following, with teachers of the visually impaired contributing on a Google Group, and a ton of people downloading the models. [Joan] and [Whosawhatsis] are getting a lot of great feedback and growing the range of contributors, making this the start of an awesome community and a great Hackaday Prize entry.

The HackadayPrize2016 is Sponsored by: