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Robots, children's blocks, wooden clocks, its all good! Here's my idea and here's the [[page]] on RepRap's wiki where we can log in and click "edit".
Re: Additive vs Subtractive fabrication - 16 years ago
One trick you can do with a milling head on a 3D printer is to deposit plastic and then machine it a little bit. Say you want a precisely sized block with a cm through a precisely sized through hole, but there's a little bit of slop in each layer from the plastic spreading and moving before cooling. So you use the milling head after depositing each layer to clean it up a bit.by SebastienBailard - Plastic Extruder Working Group
Re: Additive vs Subtractive fabrication - 16 years ago
One reason - a mill (or router) has to be quite stiff to resist all the vibration from the cutting head. For this reason, it would be difficult to make a decent mill mostly out of machinable wax or thermoplastic. If we were to make it out of steel or aluminum, it would essentially duplicate commercially available tools and not be particularly revolutionary. Secondly, fabricating a conventionalby SebastienBailard - Plastic Extruder Working Group
Re: Neil Gershenfeld: The beckoning promise of personal fabrication - 16 years ago
Andy, check out: All the parts you need to do up an algae that makes thermoplastic, maybe. Regarding building tools, I'm more interested in using a RepRap to make the machines which are difficult or expensive to source commercially. i.e. CNC routers, laser cutters, and so on. Drill presses, not so much.by SebastienBailard - General
Re: Building CNC machines from Epoxy+Granite - 16 years ago
"Are you perchance looking to use such a machine for sculpture ??" Maybe eventually; if I start working in a large scale, I could use it to route out the foam for a large relief work or the foam slices to make up the body of a larger statue. I'm still in the 'boy that would be really cool' stage. I think it's worth highlighting the fact that we probably want to design up three CNC routers, sby SebastienBailard - Casting and Moldmaking Working Group
Re: Building CNC machines from Epoxy+Granite - 16 years ago
Andy, What size workspace are you envisioning? Edit: Something this size, 24"x15", would be useful in the small workshop and for what you're doing, but that's moving gantry rather than moving table. Personally, I want something big, 4'x8' ideally. That's a different project, you wouldn't want to build a huge cnc route to do pcbs. We should pick Viktor's brain regarding the laser cutter stufby SebastienBailard - Casting and Moldmaking Working Group
Re: Building CNC machines from Epoxy+Granite - 16 years ago
Two questions: Are these materials pretty straightforward to use in a small workshop? Is ventilation an issue? Are people interested in using this to build, say, a laser cutter and a large CNC router?by SebastienBailard - Casting and Moldmaking Working Group
Re: Neil Gershenfeld: The beckoning promise of personal fabrication - 16 years ago
Maybe we should respond by getting to work designing and building fabrication machines we can build using a RepRap. Say, a laser cutter and a large CNC router. Would people be interested in this?by SebastienBailard - General
Journal Club! - 16 years ago
I've been thinking that we don't pay much attention to the published literature. So I hereby start ... The RepRap Joural Club! Here is one book and two articles about RP which people may find interesting. Forrest's thoughts on them: [3dreplicators.com] Please email me at penguin at supermeta dot com if you want me to email you a copy of one or both articles. I'd attach them as files, but therby SebastienBailard - General
Re: rep rap user-group - 16 years ago
Kyle, their 3D printer may cost ~$6/cubic inch if it's a FDM type. You're better off buying a mini-mill or building a RepStrap out of wood or metal.by SebastienBailard - Canada, Toronto RepRap User Group
Re: 8mm Rod From McMaster-Carr - 16 years ago
I got my 5/16" smooth rod and threaded rod from a place listed under "Steel Distributors" in my yellow pages. These are the guys that supply building contractors, but they'll deal with you, too. Somewhat cheaper than a hardware store, and they'll have enough for the project. (Hardware stores rarely do.)by SebastienBailard - Mechanics
Re: Does an object need to be fabbed all at once? - 16 years ago
I've been thinking it would be useful to set breakpoints in order to insert all those trapped nuts.by SebastienBailard - Plastic Extruder Working Group
Re: Objects.RepRap.Org - Any volunteers? Let's build a file library! - 16 years ago
While we're hashing this out, I'll put up a newer version of the mediawiki at objects.reprap.org this weekend, and then spend a while loading the RepRap printable parts onto it. I'll think I'll spend a little while longer spam-proofing it this time. I'm still not convinced that a mediawiki will meet our needs, longterm.by SebastienBailard - Administration, Announcements, Policy
Objects.RepRap.Org - Any volunteers? Let's build a file library! - 16 years ago
As per the posting in the blog, we're discussing what we want to do for an object file library. Hint: maybe not a wiki.by SebastienBailard - Administration, Announcements, Policy
Re: Building CNC machines from Epoxy+Granite - 16 years ago
Here's a photo from the cnczone index-thread which I liked. Viktor, you may want to include links when you mention the german cnc forums. While I'm not deutscheophonic, some people are.by SebastienBailard - Casting and Moldmaking Working Group
Cheapish CNC router kits. - 16 years ago
Patrick Hood-Daniel is offering a CNC router kit for $405.00 (unassembled, not including shipping from Houston TX, motors, or drive electronics.) The machine is mostly made from MDF and fasteners, and has a 2'x4'x?" working area. This is the introductory pre-sale price. The post sale price is $550. Patrick is a decent sort and his machine will probably make a great repstrap; it's good enouby SebastienBailard - General
Building CNC machines from Epoxy+Granite - 16 years ago
There's a very long thread on cnczone, indexed here: about building cnc machines using a mixture of granite or quartz aggreate and small amounts of epoxy. This has applications for making RepRaps and for making CNC mills and routers using RepRaps.by SebastienBailard - Casting and Moldmaking Working Group
Re: Vigyan Ashram - 16 years ago
Sure, after the 1.0 release, when we've got all the machine time we need, Viktor. Gene, check out: It's a small wind generator. It gets its power from a small taut band which flutters in the wind. A magnet is glued one end of the band, where its oscillations induce currents in two wire coils.by SebastienBailard - General
Re: Vigyan Ashram - 16 years ago
Here's a project in a similar spirit, to create an industry making cargo bikes in Ghana. They make the bike frames out of bamboo, epoxy, and metal bits.by SebastienBailard - General
Re: is GPL the best choice for an open source hardware licence? - 16 years ago
Here's an interesting article on license proliferation. And here's the most egregious example:by SebastienBailard - General
Re: Wanted - Z drive pulley - 16 years ago
What about using a dowel or suchlike as reinforcement?by SebastienBailard - Wanted
Re: frikkin' laser beams - 16 years ago
The hard(er) part is the optics; you need the bumpiness of the optics to be smaller than the wavelength of light that you're using. According to Sam's Laser FAQ, "the output of a CO2 laser is medium-IR radiation at 10.6 um", which is << than our print size of 0.5 mm ( 500 um ). (I'm not sure what size features we'll get with inkjet printing.) The glass tubing is comparatively cheap: $10by SebastienBailard - Laser Cutter Working Group
Re: Poker-working device - 16 years ago
I think there are some people doing work with usb and emc, but we went with a java-based driver in order to run on anything. If it was just you or me doing this, it would probably be in C using the parallel port in linux. Since we want most of the world using these machines, we need to make compromises.by SebastienBailard - Russia RepRap User Group
Re: Poker-working device - 16 years ago
Look at emc, a realtime linux based machine controller. It will be easy if your robot is controlled by a parallel port, with a simple protocol like "wire 1 (HI/LO) indicates (+X/-X) direction for the x-axis, wire 2 pulses mean move one step on X, etc." If your robot requires something more complicated, you may be able to get emc to do it.by SebastienBailard - Russia RepRap User Group
Vigyan Ashram - 16 years ago
Has anyone read Neil Gerhendfeld's book, FAB? He mentions a school, Vigyan Ashram, in a drought-prone, Indian town of 10,000. BBC NEWS | In pictures | Vigyan Ashram It is interesting to see what they are up to. Reports (pdfs) blog - hearing aids, led lamps, bio gas generators, etc. fablabinnova - Pedal Power "This (bike generator) mechanism is a big success in a Thane school where 32 chiby SebastienBailard - General
Re: Robot catched - 16 years ago
'Yes, it's some kind of servo motor, manually created. In russian, "steppers" and "servomotor" are often mixed. Now I understand the difference clearly. Stepper is specially designed motors with lot number of poles, servo is motor with some feedback system - is it correct?' Yes. Steppers have the coils on the outside, and a rotor with multiple magnetic regions. Nomenclature (naming) may get mby SebastienBailard - Russia RepRap User Group
Re: Assargadon's self-introduction. - 16 years ago
This is why I suggested not disassembling the motors; "... This is a serious misnomer. It should read: DO NOT DISASSEMBLE without reading the manual. The stator must not be removed from the 20-pole magnet without at the same time pushing in an iron plug of the same diameter. The magnet will demagnetize itself instantly if the magnetic return path (the stator or "keeper") is broken even forby SebastienBailard - Russia RepRap User Group
Re: Robot catched - 16 years ago
I think the optical wheel + (DC, probably) motor combination means you have a servo motor. I would save them for future use to turn your robot into a CNC router. I believe glass, steel wire, or kevlar reinforced rubber belt is pretty reliable for these applications. Consider the timing belt in a car. If you are curious, go look up some specifications on There are a number of ways to measurby SebastienBailard - Russia RepRap User Group
Re: Cartensian Robot Designs (Pros and Cons) - 16 years ago
You may want to consider using a CNC-ready Taig Mill or equivalent as your RepStrap. Pluses - It works out of the box, and you'll also be able to mill aluminum and steel. Minuses - Somewhat expensive, and if you have a machine shop on hand, it unecessarily duplicates existing resources. More subtly, using a premade apparatus may defeat one learning portion of the senior project, the machine-buiby SebastienBailard - Mechanics
Re: Cheap digital storage oscilloscope - 16 years ago
The xoscope sound-card scope only works for audible-sound frequencies; ~20Hz to ~20KHz or so. This is because it's using your computer's microphone-in EDIT (I mean RCA jack) END_EDIT jack, which isn't designed to sample > 20KHz frequencies. I'm going to be ordering a bunch of parts to make a whole bunch of these for Dorkbot-ottawa-gatineau, the local electronic art group's soldering party /by SebastienBailard - Controllers
Re: Acrylic notches - 16 years ago
Try travers.com for canada as well. It's what all the machinists in Ottawa recommended to me.by SebastienBailard - Mechanics