Homemade Stereolithography?

Dissatisfied with your plastic extrusion-based home 3D printer? Looking for a mechanical build challenge? Perhaps you'd be interested in checking out the Laser 3D Printer on Instructables. 

 

This project describes how to build a stereolithography (SLA) machine. You should know, however, that the SLA build process is quite different from typical RepRap-style 3D printers that extrude plastic. Instead, SLA illuminates a liquid resin with UV light, creating a layer of the object when the resin solidifies when exposed to the UV light. By gradually lowering the print into the resin and fusing new layers at the surface of the liquid resin, the object is gradually built. 

 

The advantage of this system is that the resolution can be much better than extrusion-based alternatives, since the equivalent of the "nozzle" is simply how fine you can focus the UV light. 

 

While this looks like a great project we wonder about its legality. The SLA process has been deeply patented by commercial companies and the question must be asked whether they would permit it to proceed. Certainly if this project went into commercial business some questions would be asked. It will be interesting to see what happens. 

 

Via Instructables (Hat tip to Andy and Snowbear)

Hi Res Home 3D Printer Update

We're perusing Junior Veloso's blog - he's the fellow who's developing a very high-resolution personal 3D printer. The device is quite different from most home RepRap-derived 3D printers in that it doesn't heat and extrude plastic. Instead, Veloso's printer uses light to solidify resin, layer by layer. The results are pretty amazing - click the image to see the full size close-up image. 

 

This approach has several advantages: 

 

• Each layer can be created all at once, as opposed to extrusion-based printers that must mechanically trace all print areas. This makes the print process run quickly
• The resolution can be much higher because it's limited by the focal ability of the light projector and the resin's speed of solidification rather than the mechanical movements of an extruder

 

But there may be some disadvantages as well: 

 

• The cost of the resin is said to be high, but may drop when demand increases
• "Wet" printing can be messier than "dry" extrusion, where there's nothing to spill or drip

 

Veloso indicates he's interested in developing this concept into a mostly open source concept, with some him providing certain key components. He's attempting to procure a patent that should protect him from lawsuits - if his approach has not already been patented by an existing manufacturer. 

 

We're wondering how this may play out. If we look at the example of RepRap, their technology breakthroughs spurred the development of many inexpensive 3D printer companies, some of which are growing fast. But could Veloso's concept share the same result? Could we see several companies built on his tech in the future? If they can produce output like we're seeing that could be a good thing. 

 

Via 3Dhomemade

What is OHANDA?

OHANDA is the Open Source Hardware and Design Alliance, an initiative that has developed "Four Freedoms" that can be associated with an open design to ensure proper open source use. Their idea is to create an icon that may be displayed on hardware to indicate the permitted usage, similar to a "CC" license in a way. Their description: 

 

The proposed solution with OHANDA is a label in the sense of a trademark. The label will connect the 4 Freedoms with any kind of physical device through OHANDA. Think the label like other common certificates such as FCC or CE mark. The mark permits a user of the product these four freedoms: 

 

• Freedom 0: The freedom to use the device for any purpose.
• Freedom 1: The freedom to study how the device works and change it to make it to do what you wish. Access to the complete design is precondition to this.
• Freedom 2: Redistribute the device and/or design (remanufacture).
• Freedom 3: The freedom to improve the device and/or design, and release your improvements (and modified versions in general) to the public, so that the whole community benefits. Access to the complete design is precondition to this.

  

The obvious question is why can't we just use a standard open source copyleft license instead? Why go to the trouble of making official logos? The answer is actually quite straightforward: Copyleft is derived from legal definitions of Copyright, and Copyright applies only to non-physical products. Physical products are typically protected with Patents. But the problem with Patents is that they are notoriously difficult to put in place, far beyond the ability of many makers. 

 

OHANDA's solution is pretty simple: You register your product and receive a special "producer id", which legally means you're granting the four freedoms to the user. You then slap the OHANDA label containing your key information on the product. This unique label provides a link back to the product's current documentation so the original designer and intent is maintained. 

 

Via OHANDA and Slideshare

AdderFab!

We've been following the folks at Open3DP for a while now as they proceed through experiments in 3D Printing. Lately they've been working on perfecting printing molds that have revolutionized the production of RepRap Prusa Mendel 3D printer parts. However, we now see they're working on an entirely new project: an inexpensive, presumably open-source powder-based 3D printer. 

 

Their video shows a very early experiment, and while the result is modest, the direction is clear. They're making a printer that could enable hobbyists to produce new kinds of objects with a different technology. 

 

How different? The big difference with powder printing is that it by default acts as it's own support material. Layer-by-layer printing occurs, but each layer can be printed on undisturbed powder below. This means that whole new classes of 3D objects can be printed, especially those requiring difficult support structures when printed on "normal" extrusion-based hobbyist 3D printers. 

 

Another possibility is that some of the companies currently based on or directly marketing open source personal manufacturing equipment (e.g. MakerBot, BotMill, etc.) might eventually consider adding this type of equipment to their product lines. However, we see one tricky problem: printing in powder is incredibly messy, and really requires dedicated equipment to vacuum up the residue as well as cleaning and finishing the printed object. Likely such a printer might not be successful unless accompanied by appropriate finishing equipment. 

 

There's not much information available in their post other than "We would like to share something we made", but this looks very interesting, indeed. We're watching for further developments. 

 

Via Open3DP

Metalcasting Breakthrough

Those inventive folks at the University of Washington are at it again. This time they've been working on a simple formula for cementenous metalcasting. In other words, material with which you can make an effective mold for molten metal casts. At one point, they were using this recipe: 

 

• 1000 parts VersaBond
• 250 parts Maltodextrin
• 250 parts PVA powder

 

When mixed with just the precise amount of moisture and deposited appropriately by a 3D printer, you'll get yourself a near-rock-hard mold suitable for sloshing in a hot metallic liquid of your choice. What will your first cast be? We know what Open3DP's will be (see image above). 

 

However, after subsequent experiments with other substances including - apparently - Rice Wine (all for good academic use, we're quite certain), they have arrived at the ultimate formula: 

 

There is no formula. Just go to the hardware store and purchase a 50 pound bag of USG Hydroperm for USD$30!

 

That's perhaps the simplest and best answer one could hope for. Well, done, Open3DP!

 

Via Open3DP and Open3DP

Open CASCADE

Readers might be familiar with Open CASCADE, but for those who aren't it's an open source software development framework that "includes components for 3D surface and solid modeling, visualization, data exchange and rapid application development."

The software is produced by Open CASCADE S.A., who make their money by providing consulting, support and custom development, as any good open source company should. But many folks use the open source version on their own.

Open CASCADE has a long heritage, having been initially created in the 1990's. So how does one use it today? One good way is to use PythonOCC, a "3D CAD/PLM development library for the Python programming language" built on top of Open CASCADE. PythonOCC is available on major platforms in both 32 and 64 bit versions, providing these features:

• 3D hybrid modeling
• Data exchange (support of STEP/IGES file format)
• GUI management support (wxPython, PyQt, python-xlib)
• Parametric modeling
• Advanced meshing features

In fact, they've just released PythonOCC version 0.4, which includes these features:

• pythonOCC 0.4 comes with new advanced meshing features coming from the smesh project
• many new samples
• the OCC wrapper was improved (few missing modules were added, typical C++ mechanisms were pythonized)
• 64 bits support
• New graphical backends (PyQt and python-xlib)
• MacOSX Snow Leopard support
• better installation script
• as usual, many minor fixes/enhancements in the whole API

Via OpenCASCADE, PythonOCC and the PythonOCC Blog (Hat tip to Bryan)

Definitive Guide Complete?

Make Magazine has produced a complete list of open source hardware projects, ranging in categories from 3D Printing, Arduino, Clocks, Development Platforms, Green Energy, Games, Medical, Robotics and many other areas. The category of interest to us, is of course, 3D printing. There we find the major open projects listed:

• Contraptor
• Fab@Home
• MakerBeam
• MakerBot
• RepRap

And that is indeed the list of the major projects, but we wonder whether there are other smaller projects that might be considered for such a list? Over the past two years we've written on several independent projects attempting various angles on 3D printing. But at least so far, none have reached the heights these five have made.

Via Make

Let's Download Some Hardware!

Bryan Bishop and Ben Lipkowitz talk about their new open source venture: SKDB. What is it? It's a open source hardware distribution framework that takes cues from the highly successful software world.

The software world was held back for decades by centrally controlled proprietary paradigms, but blossomed when open source principles took hold. Today we see open source software dominating almost all aspects of software, and software designers often spend their time designing higher-level systems by using open source software as building blocks.

That success was most visibly demonstrated by Debian, a project to produce a specific distribution of the Linux operating system. One of Debian's key features was a means to quickly obtain software or software upgrades very easily by using the APT-GET command. The command pulls down not only the software you requested, but all related items it depends on. This approach was used by Ubuntu, who produce one of the most popular operating systems on the planet.

Bishop and Lipkowitz believe the same approach could break open the 3D fabbing market by making it terrifically easy for makers to access high quality conglomerations of models. The software makers went farther than just using software, however, as they built more complex software on top of simpler components distributed via APT-GET. The same forms of assembly are used to produce 3D objects, and thus the theory is that similar product complexity can be achieved.

Via Youtube (part 1), YouTube (part 2), YouTube (Part 3), Slides here and the SKDB site (Hat tip to Bryan)