3D Printed Ribs For Not 3D Printed Planes

September 8, 2017 by Brian Benchoff 14 Comments

A few months ago, [Tom] built a few RC planes. The first was completely 3D printed, but the resulting print — and plane — came in a bit overweight, making it a terrible plane. The second plane was a VTOL tilt rotor, using aluminum box section for the wing spar. This plane was a lot of fun to fly, but again, a bit overweight and the airfoil was never quite right.

Obviously, there are improvements to be made in the field of 3D printed aeronautics, and [Tom]’s recent experiments with 3D printed ribs hit it out of the park.

If you’re unfamiliar, a wing spar is a very long member that goes from wingtip to wingtip, or from the fuselage to each wingtip, and effectively supports the entire weight of the plane. The ribs run perpendicular to the spar and provide support for the wing covering, whether it’s aluminum, foam board, or monokote.

For this build, [Tom] is relying on the old standby, a square piece of balsa. The ribs, though, are 3D printed. They’re basically a single-wall vase in the shape of a wing rib, and are attached to the covering (foam board) with Gorilla glue.

Did the 3D printed ribs work? Yes, of course, you can strap a motor to a toaster and get it to fly. What’s interesting here is how good the resulting wing looked. It’s not quite up to the quality of fancy fiberglass wings, but it’s on par with any other foam board construction.

The takeaway, though, is how much lighter this construction was when compared to the completely 3D printed plane. With similar electronics, the plane with the 3D printed ribs weighed in at 312 grams. The completely 3D printed plane was a hefty 468 grams. That’s a lot of weight saved, and that translates into more flying time.

You can check out the build video below.

Continue reading “3D Printed Ribs For Not 3D Printed Planes” →

I’ve Seen The Future And It’s Full Of Freakin’ Huge Bricks

September 8, 2017 by John Baichtal 31 Comments

“Did you know you can 3D-print LEGO bricks that can actually be used as regular LEGO?”–me, in 2009

Those magical words made real to me the wonder that was 3D printing. It was a magical time! Everyone was 3D printing everything, though most of it wasn’t very good because the technology wasn’t there. But just as every technology goes through an evolution, the goalposts of coolness move on past what used to be remarkable to the new thing everyone’s talking about.

These days, no one is going to be more than mildly curious about your 3D-printed LEGO brick. Still, when you look at that uneven lump of plastic as being just one step in an evolution, it’s pretty momentous. What I’m saying is that we’re looking at a future that can be described in three words: Freakin’ Huge Bricks.

Continue reading “I’ve Seen The Future And It’s Full Of Freakin’ Huge Bricks” →

Polyurethane, Meet 3D Printing

September 3, 2017 by Elliot Williams 9 Comments

3D printing makes prototyping wonderful. But what do you do when your plastics of choice just aren’t strong enough? For [Michael Memeteau], the answer was to combine the strength of a vacuum-poured polyurethane part with the ease of 3D-printed molds. The write-up is a fantastic walk through of a particular problem and all of the false steps along the way to a solution.

The prototype is a connected scale for LPG canisters, so the frame would have to support 80 kg and survive an outdoor environment. Lego or MDF lattice were considered and abandoned as options early on. 3D printing at 100% infill might have worked, but because of the frame’s size, it would have to be assembled in pieces and took far too long anyway.

The next approach was to make a mold with the 3D printer and pour the chosen polyurethane resin in, but a simple hollow mold didn’t work because the polyurethane heats as it cures. The combined weight and heat deformed the PLA mold. Worse, their polyurethane of choice was viscous and cured too quickly.

The solution, in the end, was a PET filament that deforms less with heat, clever choice of internal support structures to hold the stress in while being permeable, and finally pouring the polyurethane in a vacuum bag to help it fill and degas. The 3D-printed hull is part of the final product, but the strength comes from the polyurethane.

Mold-making is one of the killer apps of 3D printing. We’ve seen 3D prints used as molds for spin-casting hollow parts, and used as a sacrificial shell for otherwise epoxy parts. But for really complex shapes, strength, and ease of fabrication, we have to say that [Michael]’s approach looks promising.

How Low-Power Can You Go?

September 1, 2017 by James Hobson 28 Comments

[lasersaber] has a passion: low-power motors. In a bid to challenge himself and inspired by betavoltaic cells, he has 3D printed and built a small nuclear powered motor!

This photovoltaic battery uses fragile glass vials of tritium extracted from keychains and a small section of a solar panel to absorb the light, generating power. After experimenting with numerous designs, [lasersaber] went with a 3D printed pyramid that houses six coils and three magnets, encapsulated in a glass cloche and accompanied by a suitably ominous green glow.

Can you guess how much power and current are coursing through this thing? Guess again. Lower. Lower.

Under 200mV and 20nA!

Continue reading “How Low-Power Can You Go?” →

XYZ Printing Unveils Inkjet-Based Filament Printer

August 31, 2017 by Brian Benchoff 21 Comments

XYZ Printing, makers of the popular da Vinci line of 3D printers, have just released one of the holy grails of desktop 3D printing. The da Vinci Color is a full-color, filament based printer. How does this work? A special filament (Color PLA, although this filament is white in color) is extruded through a nozzle like any other 3D printer. Color is then added layer by layer by a system of inkjets in the head of the printer. Yes, it’s a full-color 3D printer, and yes, people have been suggesting this type of setup for years. This is the first time it’s been made real.

The specs for this printer are about what you would expect from any other filament-based printer in 2017. The build volume is 200 x 200 x 150mmm, the print bed has auto-leveling (although strangely doesn’t have a heated bed), and the user interface is a 5-inch color LCD. The da Vinci Color is available for preorder right now for $2,999.

You can check out a few pics of samples printed on the da Vinci Color below:

Continue reading “XYZ Printing Unveils Inkjet-Based Filament Printer” →

Boredom + Lasers = Projector!

August 29, 2017 by James Hobson 7 Comments

[Krazer], a post-doctoral researcher at MIT, loves him some lasers. When out of boredom one afternoon he hatched an idea for a laser projector, it grew until a few years later he wound up with this RGB laser for a projector — Mark IV no less.

In addition to 3D-printing the parts, the major innovation with this version is the ability to re-align the lasers as needed; tweaking the vertical alignment is controlled by a screw on the laser mounts while the horizontal alignment is done the same way on the mirror mounts. This simplifies the design and reduces the possibility of part failure or warping over time. An additional aluminium base epoxied to the projector aims to keep the whole from deforming and adds stability. With the help of a mirror for the final alignment — sometimes you must use what you have— the projector is ready to put on a show.

True to the spirit of the art [Krazer] used all open source software for this iteration, and sharing his designs means you can build your own for around $200. As always with lasers take extra precautions to protect your eyes! This 200mW setup is no joke, but that doesn’t mean fun and games are out of the question.

3D Printing T-Shirt Designs

August 27, 2017 by Michael Uttmark 28 Comments

Usually, t-shirt designs are screen printed, but that’s so old school. You have to make the silkscreen and then rub paint all over – it’s clearly a technique meant for the past. Well, fear not, as [RCLifeOn] is here to bring us to the future with 3D Printed T-Shirt Designs.

[RCLifeOn] affixes t-shirts to his print build platform and boom: you’ve got 3D printed graphics. He started by using PLA which, while it looked great, wasn’t up to a tussle with a washing machine. However, he quickly moved on to NinjaFlex which fended much better in a wash cycle. While the NinjaFlex washed better, [RCLifeOn] did have some issues getting the NinjaFlex to adhere to the t-shirt. With a little persistence and some settings tweaking, he was able to come out ahead with a durable and aesthetically pleasing result.

Now, 3D printing isn’t going to replace screen printing, but it’s also not going to replace injection molding. What 3D printing lacks in speed and efficiency, it makes up in setup time & cost. In other words, if you need 50 t-shirts of the same design, screen printing is the way to go. But, if you need 50 shirts, each with a different design, you just might want to follow in [RCLifeOn’s] footsteps.

Anyways, we don’t have much on 3D printing t-shirts, but we do have other useful information on 3D printing slinkys and 3D printing project enclosures. And, if you’d rather do it the old-school way, we can show you how to silkscreen all the things.