Hackaday Links: August 30, 2015

A month ago, we ran a post about [Jim]’s rare and strange transparent microchips. He’s back at it again, this time taking a look at the inner workings of MOSFETs

The Unallocated Space hackerspace is moving, and they’re looking for a few donations to get the ball rolling.

Yes, it’s a Kickstarter for a 3D printer, but the LumiPocket is interesting, even if only on the basis of the engineering choices. It’s a UV laser resin printer, and they’re using a SCARA arm to move the laser around. They’re also doing a top-down resin tank; it requires more resin, but it seems to work well enough.

Around DC or northern Virginia? We’re going to be there on September 11th through the 13th. We’re holding a Hackaday Prize Worldwide meetup at Nova Labs in Reston, Virgina. Sign up now! Learn KiCAD with [Anool]! Meet [Sudo Bob]! It’ll be a blast.

Not around DC or NOVA? This Wednesday we’ll be hosting another chat on .io.

The GEnx is one of the most beautiful and advanced engines in the world, and that means [Harcoreta] oven on the RC groups forums has made one of the most beautiful electric ducted fans in the world. On the outside, it looks like a GEnx, including reverse thrust capabilities, but inside it’s pure electronics: a brushless motor rotates a 100mm, 18-blade fan. He’s hoping to mount it on a Bixler (!). We can’t wait for the video of the maiden.

3D Printering: Maker Faire And Resin Printers

Of course Maker Faire was loaded up with 3D printers, but we’re no longer in the era of a 3D printer in every single booth. Filament-based printers are passé, but that doesn’t mean there’s no new technology to demonstrate. This year, it was stereolithography and other resin-based printers. Here’s the roundup of each and every one displayed at the faire, and the reason it’s still not prime time for resin-based printers.

predictaFormlabs

Of course the Formlabs Form 1+ was presented at the Bay Area Maker Faire. They were one of the first SLA printers on the market, and they’ve jumped through enough legal hoops to be able to call themselves the current kings of low-cost laser and resin printing. There were a few new companies and products at the Faire vying for the top spot, and this is where things get interesting.

The folks at Formlabs displayed the only functional print of all the resin-based 3D printing companies – a tiny, tiny Philco Predicta stuffed with an LCD displaying composite video. The display is covered by a 3D printed lens/window. That’s the closest you’re going to get to an optically clear 3D printed part at the Faire.

XYZPrinting Nobel

The Eiffel tower, an architectural model, and a Bratz doll, all printed on the XYZPrinting Nobel
The Eiffel tower, an architectural model, and a Bratz doll, all printed on the XYZPrinting Nobel

XYZPrinting, the company famous for the $500 printer that follows the Gillette model: sell the printer cheap, sell expensive replacement filament cartridges, and laugh all the way to the bank. Resetting the DRM on the XYZPrinting Da Vinci printer is easy, the proprietary host software is done away with, and bricked devices are not. Time for a new market, huh?

Enter the XYZPrinting Nobel, a resin printer that uses lasers to solidify parts 25 microns at a time. The build volume is 125x125x200mm (5x5x7.9″), with an X and Y resolution of 300 microns. Everything prints out just as you would expect. As far as laser resin printers go, it’s incredibly cheap: $1500. It does, however, use XYZware, the proprietary toolchain forced upon Da Vinci users, although the Nobel is a stand-alone printer that can pull a .STL file from a USB drive and turn it into an object without a computer. There was no mention of how – or if – this printer is locked down.

DWS Lab XFAB

This Shrek is the highest resolution 3D printed object I've ever seen.
This Shrek is the highest resolution 3D printed object I’ve ever seen.

You’ve seen the cheapest, now check out the most expensive. It’s the DWS Lab XFAB, an enormous and impressive machine that has incredible resolution, a huge build area, and when you take into account other resin printers, a price approaching insanity.

First, the price: $5000 officially, although I heard rumors of $6500 around the 3D printing tent. No, it’s not for sale yet – they’re still in beta testing. Compare that to the Formlabs Form 1+ at $3300, or the XYZPrinting Nobel at $1500, and you would expect this printer to be incredible. You would be right.

The minimum feature size of the XFAB is 80 microns, and can slice down to 10 microns. Compare that to the 300 micron feature size of the Form 1+ and Nobel, and even on paper, you can tell they really have something here. Looking at the sample prints, they do. These are simply the highest resolution 3D printed objects I’ve ever seen. The quality of the prints compares to the finest resin cast objects, machined plastic, or any other manufacturing process. If you’re looking for a printer for very, very high quality work, this is what you need.

Sharebot Voyager

SharebotAlso on display – but not in the 3D printing booth, for some reason – was the Sharebot Voyager. Unlike all the printers described above, this is a DLP printer; instead of lasers and galvos, the Voyager uses an off-the-shelf 3D DLP projector to harden layers of resin.

Strangely, the Sharebot Voyager was stuck in either the Atmel or the Arduino.cc (the [Massimo] one) booth. The printing area is a bit small – 56x96x100mm, but the resolution – on paper, mind you – goes beyond what the most expensive laser and galvo printers can manage: 50 microns in the X and Y axes, 20 to 100 microns in the Z. Compare that figure to the XFAB’s 80 micron minimum feature size, and you begin to see the genius of using a DLP projector.

The Sharebot Voyager is fully controllable over the web thanks to a 1.5GHz quad core, 1GB RAM computer that I believe is running 32 bit Windows. Yes, the spec sheet said OS: 32 bit Windows.

There were no sample prints, no price, and no expected release date. It is, for all intents and purposes, vaporware. I’ve seen it, I’ve taken pictures of it, but I’ve done that for a lot of products that never made it to market.

The Problem With Resin Printers

Taking a gander over all the resin-based 3D printers, you start to pick up on a few common themes. All the software is proprietary, and there is no open source solution for either moving galvos, lasers, or displaying images on a DLP projector correctly to run a resin-based machine. Yes, you heard it here first: it’s the first time in history Open Source hardware folk are ahead of the Open Source software folk. Honestly, open source resin printer hosts is something that should have been done years ago.

This will change in just a few months. A scary, tattooed little bird told me there will soon be an open source solution to printing in resin by the Detroit Maker Faire. Then, finally, the deluge of resin.

Clever Chemistry Leads to Much Faster 3D Printing

Resin printing, it can be messy but you get really great resolution thanks to the optical nature of curing the sticky goo with light from a projector. Soon it will have a few more notches in its belt to lord over its deposition cousins: speed and lack of layers. A breakthrough in resin printing makes it much faster than ever before and pretty much eliminates layering from the printed structure.

The concept uses an oxygen-permeable layer at the bottom of the resin pool. This inhibits curing, and apparently is the source of the breakthrough. The resin is cured right on the border of this layer and allows for what is described as a continuous growth process rather than a layer-based approach. One of the benefits described is no need for resin to flow in as the part is extracted but we’re skeptical on that claim (the resin still needs to flow from somewhere). Still, for us the need to work with resin which is expensive, possibly messy, and has an expiry (at least when compared to plastic filament) has kept deposition as a contender. The speed increase and claims of strength benefits over layer-based techniques just might be that killer feature.

The technology is coming from a company called Carbon3D. They are branding it CLIP, or Continuous Liquid Interface Production. After the break you can see a video illustration of the concept (which is a bit too simple for our tastes) as well as a TED talk which the company’s CEO, [Joseph Desimone] gave this month. Of course there is also the obligatory time-lapse print demo.

So what do you think: game changer or not, and why do you feel that way? Let us know in the comments.

Continue reading “Clever Chemistry Leads to Much Faster 3D Printing”

A UV Lightbox For Curing Prints

With resin printers slowly making their way to hackerspaces and garages the world over, there is a growing need for a place to cure these UV resin prints. No, they don’t come out of the machine fully cured, they come out fully solid. And no, we’re not just leaving them in the sun, because that’s not how we do things around here.

[Christopher] whipped up a post-cure lightbox meant to sit underneath his Form 1 printer. It’s made of 1/2″ MDF, with adjustable feet (something the Form 1 lacks), a safety switch to keep the lights off when the door is open, and a motor to rotate the parts around the enclosure.

The light source for this lightbox is 10 meters of ultraviolet LED strips. The LEDs shine somewhere between 395-405nm, the same wavelength as the laser diode found in the Form 1 printer. Other than a bit of wiring for the LEDs, the only complicated part of the build was the motor; [Christopher] bought a 2rpm motor but was sent a 36rpm motor. The vendor was out of 2rpm motors, so a PWM controller was added.

It’s a beautiful build that shows off [Christopher]’s ability to work with MDF. It also looks great sitting underneath his printer, and all his parts are rock solid now.

Making a Speaker with Resin, Magnets, and Wire

A speaker is just about the simplest electronic component possible, just barely more complex than resistors and wire. They’re also highly variable in their properties, either in size, shape, frequency response, and impedance. Obviously, building custom speakers would be of interest to a lot of people, but there aren’t many people out there doing it. [Madaeon] is one of those people. He created a speaker from scratch, using nothing but magnets, wire, and a bit of UV curing resin.

The frame of the speaker contains a magnet, and the coil of wire is carefully attached to the 0.1mm thin speaker cone with a bit of UV curing resin. All the parts are available on Thingiverse, but you will need a UV resin printer with a low layer height to print this thing out.

The speaker was built by [madaeon] as a demonstration of what the printer he built can do. It’s a fairly standard resin-based 3D printer built around a DLP projector. It’s also cheap, and unlike some other cheap resin-based 3D printers, there’s a reasonable likelihood his will ship within the next few months.

The Hackaday Prize Semifinalist Update

There are only a few more days until The Hackaday Prize semifinalists need to get everything ready for the great culling of really awesome projects by our fabulous team of judges. Here are a few projects that were updated recently, but for all the updates you can check out all the entries hustling to get everything done in time.


Replacing really, really small parts

accThe NoteOn smartpen is a computer that fits inside a pen. Obviously, there are size limitations [Nick Ames] is dealing with, and when a component goes bad, that means board rework in some very cramped spaces. The latest problem was a defective accelerometer.

In a normal project, a little hot air and a pair of tweezers would be enough to remove the defective part and replace it. This is not the case with this smart pen. It’s a crowded layout, and 0402 resistors can easily disappear in a large solder glob.

[Nick] wrapped the closest parts to the defective accelerometer in Kapton tape. That seemed to be enough to shield it from his Aoyue 850 hot air gun. The new part was pre-tinned and placed back on the board with low air flow.

How to build a spectrometer

spec

The RamanPi Spectrometer is seeing a lot of development. The 3D printed optics mount (think about that for a second) took somewhere between 12 and 18 hours to print. Once that was done and the parts were cleaned up, the mirrors, diffraction grating, and linear CCD were mounted in the enclosure. Judging from the output of the linear CCD, [fl@C@] is getting some good data with just this simple setup.

Curing resin and building PCBs

uv[Mario], the guy behind OpenExposer, the combination SLA printer, PCB exposer, and laser harp is chugging right along. He finished his first test print with a tilted bed and he has a few ideas on how to expose PCBs on his machine.

You don’t need props to test a quadcopter

bladesGoliath, the gas-powered quadcopter, had a few problems earlier this month. During its first hover test a blade caught a belt and bad things happened. [Peter] is testing out a belt guard and tensioner only this time he’s using plywood cutouts instead of custom fiberglass blades. Those blades are a work of art all by themselves and take a long time to make; far too much effort went into them to break in a simple motor test.

LittleRP, The Latest Of The Resin Printers

LitleRP Over the last few years, a few resin / stereolithography printers have been made a few headlines due to print quality that cannot be matched by the usual RepRap style filament printers. These used to be extremely expensive machines, but lately there have been a few newcomers to the field. The latest is the LittleRP, an affordable DLP projector-based resin printer that can be put together for under a kilobuck.

Instead of proprietary resins, the LittleRP is designed to use as many different formulations of UV curing resin as possible, including those from MadeSolid and MakerJuice. These resins are cured with a DLP projector, providing a print area of 60x40x100mm with the recommended 1024×768 projector, or 72x40x100mm with the alternative 1080p projector.

This isn’t the only resin printer that’s come out recently; SeeMeCNC recently announced their cleverly named DropLit resin printer kit, going with the same ‘bring your own projector’ idea as the LittleRP. With the price of the printer, both of these kits should cost less than $1000 USD. With the price of UV resin dropping over the last few years, it might be just the time to get in the resin printer game.