The sandpaper eventually gave out. I was pushing it pretty hard, though. I ended up running a couple screws through the extruder body and PTFE (on either side of the hole). That kept it in place. I'm thinking that it might be handy to have a groove cut near the top of the PTFE barrel, with a matching ridge inside the clamp. Give it a solid mechanical connection rather than just relying on frictiby degroof - Reprappers
Thanks, That's got it. I used ArtOfIllusion to import minimug.stl and export as a Wavefront obj file. Pepakura could read that and did a pretty decent job of unfolding it. Just for fun, I did the same thing with the corner bracket (obviously something no sane person would ever do). Eventually, it came back with the following image and the warning "this make take a long time to fold".by degroof - Plastic Extruder Working Group
OK, I wasn't going to post this because a) I'm not sure it really helped and b) it's a little weird. On the other hand, I'm getting a decent extrusion and it doesn't seem to be doing any harm, so here goes: 1. found a component lead that was the same diameter as the nozzle 2. cut a piece of filament, longer than the heater barrel 3. heated the component lead and stuck it in the end of the filaby degroof - Reprappers
Hmm, I downloaded Pepakura Designer and tried to load minimug.stl. It seems to have ignored the file.by degroof - Plastic Extruder Working Group
Nice. I did something similar once, using acetate transparencies to make a dodecahedron mould for an acrylic paperweight.by degroof - Plastic Extruder Working Group
Doesn't surprise me. The extruder is a fairly complex component with all sorts of interesting feedback loops, equilibria and interdependencies. If I remember correctly, the study of heat propagation under fluctuating temperatures led to the development of Fourier analysis. And they weren't even dealing with a motor pushing plastic filament through it.by degroof - Reprappers
A company called Freeman Manufacturing just posted a bunch of video Instructables here: They're a bit self-promoting but there's some good information too.by degroof - General
Not sure about the clamp hole. I'm guessing it's a combination of measurement system mismatch and moulding process. The thread on the other end seem perfectly fine when everything's powered done and cold. When the extruder's running, though, the heater barrel slowly slips out. It's amazing how much pressure that little gear motor can exert. I'd have everything tightened up and what I thought wby degroof - Reprappers
I ended up using the heater barrel and a pair of vicegrips to do a cheap-and-dirty bottom tap. I also put a hose clamp on it to keep it from slipping. The motor end now has sandpaper wrapped around it to keep that end from slipping. Apparently, PTFE is quite slippery. Who knew? :-)by degroof - Reprappers
I've just posted this on my blog but I'd wanted to copy it here in order to get some feedback. I built a new extruder barrel and made it relatively easy to disassemble. I heated it up, pushed HDPE through, let it cool down and took it apart. Here's what I found. These images show the motor end and nozzle end, respectively. On the motor end, there's a small amount of pooling. I'm guessing theby degroof - Reprappers
I got the host program to work in Windows. Damned if I can remember everything I needed to do to get it to work, though. I should've documented it. I remember following the instructions here: ...but running into problems with the 3D and serial libraries. I've also noticed that I have to fiddle with it every time I get a new Java runtime, copying a bunch of files into the new "ext" folder.by degroof - RepRap Host
> when i was disassembling a large laserjet printer, they had used thin > steel wires as well for driving I have an old XY plotter around somewhere that uses this method. The Y axis is the most interesting in that the cable is strung in a sideways figure 8 so that the left and right sides always move in the same direction. Ed had looked at using a similar arrangement for the Z stage on Daby degroof - General
I thought all this looked familiar. There was some discussion about bead chains on the main blog: It also just occurred to me that you can make your own using beads and monofilament: Using cylindrical beads in an H pattern, you could even do a fairly decent sprocket chain. Something like this: ...only less ornate.by degroof - Mechanics
I ended up using JB Weld too. All I managed to do with the torch was scorch the wire.by degroof - Reprappers
Yeah, the strength of the string would be key. I know from personal experience that these garlands snap easily in the hands of a four-year-old.by degroof - General
Google Alerts sent this page to me this morning: The author suggests using bead garlands instead of toothed gears. Neat idea. I wonder how you'd splice the ends together. I've got some of these at home. I might have to experiment.by degroof - General
It's funny, I was just discussing this with a friend of mine yesterday. Neither of us are chemists either, so we weren't certain how the process should work. As far as I can tell, you ferment starch to get lactic acid, then polymerize that to get PLA. We got as far as guessing that the bacteria in yogurt starter might ferment corn starch into lactic acid. For polymerization, it looked like heaby degroof - Polymer Working Group
Very interesting and entertaining video:by degroof - General
I just saw this item on Instructables: I'd never heard of self-fluxing enameled wire. Neat idea. I can see this being used with a RepRap wiring head (wrap, solder, cut). If you place chips onto your build plastic dead-bug style (pins pointed up), a wiring head could do the point-to point connections.by degroof - General
Ian Adkins Wrote: ------------------------------------------------------- > A complete Darwin kit is expected to be about >by degroof - Reprappers
ZachHoeken Wrote: ------------------------------------------------------- > yes, we're going to have those in the RRRF store > eventually. i'm ordering a set of 10 from him > soon. Thanks. I'll sit tight, then. Probably best if Ian doesn't have to mess with a bunch of one-off international orders.by degroof - General
One thing you can do is download and set up all the software. You'll need, at a minimum, the RepRap host software. You might also want to install Art of Illusion. The nice thing about RepRap is that the host software will simulate a build (using the "Null Cartesian" geometry). So, you can experiment with creating parts in Art of Illusion, export them to STL and have the RepRap software draw out tby degroof - General
Here's what I get, based on your quotes and estimating the additional electronics and hardware costs. I used an exchange rate ofby degroof - Reprappers
You'll need to populate the PCBs as well. I'd say about $100 worth of components there. There are also miscellaneous nuts and bolts to hold the whole thing together.by degroof - Reprappers
OK, so, what I should expect from my order is an extruder kit with the plastic parts rather than the machined parts, right? Sounds good. What I was asking, though, was whether you were planning on selling the plastic parts for the cartesian robot as well. Something like what Ian has here:by degroof - General
OK, now I'm confused. I saw the extruder kit on RRRF and ordered that. I haven't seen the molded RP parts there yet. Do you have those too?by degroof - General
//just about everything on the RRRF store is sold out// Uh oh, gonna need to set up a waiting list app. What do you figure the ETA is for molded plastic kits?by degroof - General
This morning, the Make: blog mentioned both RRRF and BitsFromBytes: Hope you guys are ready for an influx of new customers.by degroof - General
Of course now, from my point of view, the big question is whether to grab a kit now and pay the extra shipping or to wait a bit until they show up in the RRRF store.by degroof - General
I looked at Fab@Home at one point. Quite a bit more expensive. Koba started selling kits recently. I don't know of any other fabber projects. I think Vik Olliver and Forrest Higgs each had their own projects going at one time and incorporated their ideas into RepRap. I could be wrong on that, though. It's hard to keep the timeline straight. I first heard about RepRap in early 2005 (I appear tby degroof - General