Hazel1919, you may want to take a look at Peter's Boot-strappable Open Laser Cutter if you are not already aware of it. It uses a high power (some tens of watts, I think) CO2 laser.by MattMoses - General
Quotenophead Didn't Viktor propose such a system many moons ago? Here is Viktor's magnet-based tripodby MattMoses - General
The new rules look great! They really make it clear what the prize is about. (My only complaint is that May 31 seems like a very short deadline). As Traumflug pointed out in a related thread: If you actually want people to enter the competition, publicity is important. If this is posted to the General forum, I'm sure it will get more attention. It wouldn't hurt to send an announcement overby MattMoses - Kartik M. Gada Humanitarian Innovation Prize
Hi Hazel1919, It is great to see so much enthusiasm for this project. Two questions: 1) Is there any reason not to use a double-bin powder handler, like this one? It seems that if you use a "tried and true" powder handler you will have more time to spend on the more challenging parts of the project. As they say, "Don't fix it if it isn't broken". 2) You say you are building a new forum and neby MattMoses - General
How you begin depends on your level of experience and the tools, materials, and workspace you have access to. Assuming you have basic lab skills, a few tools, and a decent place to do experiments, I would suggest starting with copper electroplating. The process is simple and forgiving, the materials are readily available (but toxic!) and there are a zillion tutorials on youtube (see links below).by MattMoses - General
Thanks for the update, bobc (and Forrest). Is there any indication that extending the deadline will result in more than zero entries? Maybe the organizers of the prize could take this opportunity to change the rules a little. Most of the rules, by themselves, seem sensible (to me anyway). But taken as a whole, the rule package always seemed pretty strange. Is the device supposed to be for humaby MattMoses - Kartik M. Gada Humanitarian Innovation Prize
Well, as far as I know, electroplating and electroforming are really the same thing, physically. People just call it "electroforming" if the deposited layer is thick (relatively speaking) and "electroplating" if it is thin.by MattMoses - General
The deposition rate (the change in layer thickness per time in units of, for example, meters-per-second) is proportional to current density (in units of, for example, amps-per-meters^2). The current density is limited because if it gets too high you start getting bad quality deposits (porous, spongy, contaminated, etc) and you get bubbles due to electrolysis and other problems. So the depositionby MattMoses - General
A guy called Jeff Thompson did some work on this back in 1998. His writeup can still be found here. His experiments were based on this patent: US5641391 Three dimensional microfabrication by localized electrodeposition and etching Microfabrica uses a process called EFAB where a) Metal A is plated through a mask, b) the mask is removed and Metal B is plated over Metal A, c) everything is planarby MattMoses - General
QuoteBilding solid 3D-parts won't be practical with this methode Well, I tried proposing something similar a few weeks ago* in the other other Metal Print thread but the idea was dismissed as impossible. So if the general consensus of the skeptics is changing from "not possible" to "not practical" then at least we are moving in the right direction! But seriously, I think it may be possible toby MattMoses - General
People might also be interested in this paper. They do pressure welding of aluminum, copper, and nickel at room temperature: Pressure Welding of Thin Sheet Metals: Experimental Investigations and Analytical Modeling by Mahabunphachai et al Journal of Manufacturing Science and Engineering, Aug 2009 link Another search term to use when looking up these processes is "solid state bonding" or "solidby MattMoses - General
I humbly offer to you a quote from the wikipedia page on cold welding: Quotewikipedia Cold or contact welding is a solid-state welding process in which joining takes place without fusion/heating at the interface of the two parts to be welded. Unlike in the fusion-welding processes, no liquid or molten phase is present in the joint. Cold welding was first recognized as a general materials phenomby MattMoses - General
Quotekonwiddak Effectively a device to lay a track of wire and a spot welder to stick it to the layer below? I think this could produce a functional device! Yes! A lot of folks seem to think that the metal has to melt. The metal does not have to melt. A process by which a wire feed is spot-welded at regular, close, spacing to a growing metal part seems entirely feasible. There was a great lby MattMoses - General
As long as we're assigning credit, we shouldn't forget VDX. He was working on this back in 2007.by MattMoses - General
QuoteNewPerfection Not the place for this. I disagree. Tons (tons!) of people build new extruders, hot ends, printers, and more and then announce/advertise on this forum. If they can do it, why not this guy? We can mix business and pleasure, right? Your extruder looks nice, 3D Andy.by MattMoses - General
Anyone here remember the Reprap Research Foundation? I happily donated to it before it became broken. If it became fixed, I would consider donating again. Quotegaryhodgson I would also ask what kind of revenues the reprap project have from other channels, e.g. advertising, and whether parts of these should be utilised. Adrian addressed the topic of revenues in a message (Oct 25 2011) to the rby MattMoses - General
Quotexclusive585 I think we've started up a very important coversation We start this conversation a lot. August 18, 2012: Thingiverse Alternative Poll on Reddit September 19, 2012: Prusa Jr. Chastises & Leaves THINGIVERSE September 24, 2012: The death of Thingiverse? October 12, 2012: Can we put an organized model repository up on reprap.org?by MattMoses - General
QuoteGreg Frost I like the idea of using GitHub to store the data for models, but having a slicker front end that so that people just wanting to browse don't need to deal with the GitHub interface. That sounds like Gary Hodgson's Githubiverseby MattMoses - General
martinprice2004's comment about the pantograph reminded me of Feynman's lecture "There's Plenty of Room at the Bottom". Everyone here already knows about this lecture, right? Feynman suggested a recursive manufacturing system for making small things. He noted that "At each stage, it is necessary to improve the precision of the apparatus." RepRap users do this by a few ways. First, a lot of thby MattMoses - Developers
That must be some basement! So the micro-grippers are attached to the motion stages, in order to pick things up and manipulate on the small scale?by MattMoses - Developers
Thanks, Viktor. That is great stuff! Dr.-Ing. Uwe Jungnickel's dissertation (Tripod-2.jpg) seems to be currently living here, if anyone wants more info. There is some amazing stuff in there. I can tell it is amazing even though I can't read German.by MattMoses - Developers
Quotekonwiddak Someone made this: I don't know if its ever been made into a complete reprap. That is fdavies's Printable Sarrus Linkage He has a lot of work on thingiverse. I wonder if he is still working on this? Fdavies are you out there? QuoteVDX It's possible to make most of the parts needed for a RepRap (even a big count of the 'vitamins' and some new/superior techniques and materials)by MattMoses - Developers
QuotePMCG Has anyone yet built a reprap that (besides the electronics) was 100% reproducible by the reprap. No. QuoteVDX as long, as we can't print linear drives I think Viktor's assertion that "we can't print linear drives" is incorrect. We can print rotary motors (Printable solenoid motor, Printable flat coil motor). We can print gears and racks. So I think printing a linear drive is feasiby MattMoses - Developers
How to go from bitmap to STL. There are many ways to do this, but here is one way that uses free and open source software. It's a little convoluted, but it's free and it works. At least for me. Your mileage may vary. There is a different way to do it on Tony Buser's blog here. You will need: Inkscape Better Better DXF plugin for Inkscape OpenSCAD To install Better Better DXF, Go to the pageby MattMoses - General
CPS Wrote: ------------------------------------------------------- > What about a powder/laser reprap? There is a very nice writeup on a low cost powder/laser printer on the RepRap wiki here: SLS Wax Printerby MattMoses - Developers
QuoteTraumflug Even if you can get these temperatures and pressures with kitchen equipment, extruding alu doesn't weld it onto the layer below. Yes, Traumflug, I understand that That is why I qualified my comment with statements like "But out in the open is another question" and "of course, that is just the first problem to be solved". This is my point: We know that a welding process takes pby MattMoses - Developers
Hey Simba (and everyone else), I checked the other metal FDM thread and some of the metal-depostion pages on the wiki for mention of this and couldn't find it, so figured I'd just throw it out here. Aluminum is hot extruded in industry all the time, so a metal FDM might be more feasible than many think. Here are some videos: Animation of aluminum extrusion process Porthole die extrusion It iby MattMoses - Developers
Hi Chuck, In addition to the link above for Markus Kayser's solar sinter, there are some other projects that you might be interested in. There is a SLS wax printer on the Reprap wiki. If you want to print a binder into layers of sand, the design of the powder distribution mechanism used in this one might be informative. Open3DP does a lot of work with direct-printed ceramics and molds, and theby MattMoses - Developers
Quotedzach A Simple, Low-Cost Conductive Composite Material for 3D Printing of Electronic Sensors I like it! I wonder if it can be electroplated...by MattMoses - General
Dirty Steve, I'm just trying to help There are thousands of parts in the LDraw libraries, many of which are no longer available. It just seemed like a nice way to make use of an existing resource.by MattMoses - General