Show all posts by user
Discuss any sort of mechanical stuff here: positioning systems, gears, extruding methods, etc.
Re: will someone post the custom plastic parts to me? - 17 years ago
nophead Wrote: ------------------------------------------------------- > A lot of small > fiddly parts like bearing inserts and opto tabs > and jigs left to do. That reminds me: Does it turn out to be faster or slower to print multiple small parts at once?by degroof - Reprappers
Re: will someone post the custom plastic parts to me? - 17 years ago
Last time I did the math, I think it came out to about 5 days of continuous printing to print the entire set of parts. That's assuming no misprints or maintenance downtime. I'm not sure how long it took Vik to print his set but I'm guessing quite a bit longer than that.by degroof - Reprappers
Re: Reprap on The Register - 17 years ago
Here's some more press coverage: I see the Telegraph helpfully provided a picture of a Terminator.by degroof - General
Re: I need a cotation for my university (budget)!! - 17 years ago
Ian Adkins Wrote: ------------------------------------------------------- > we also have a more robust design for the extruder Cool! Does it have a flow control solenoid too?by degroof - General
Re: Reprap on The Register - 17 years ago
I did notice that reprap.org is very slow today.by degroof - General
Re: Is this and fab@home the same thing? - 17 years ago
There's certainly some crosstalk between the two. I've noticed ideas from one being incorporated into the other, especially in print head design. I think I saw where someone was working on fitting a RepRap extruder head onto a Fab@Home machine. Given the similar nature of the projects, it's not surprising to see some hybridization. There are certain differences, though. At the moment, Fab@Homeby degroof - General
Re: ABS Supplies? - 17 years ago
The ABS showed up yesterday. It varies a bit but seems to be about 3.09mm. I haven't run it through the extruder yet. Maybe this weekend.by degroof - Plastic Extruder Working Group
Re: Reverse Engineering - 17 years ago
There's some discussion on the anti-backlash mechanism here and here Given that you're machining the part and the fact that the anti-backlash springs don't really seem to make that much difference, you might consider skipping the springs and nuts altogether and just tapping the entire length of the hole. The only real requirements for the corner bracket are that it support the bed and fit onby degroof - Mechanics
Re: ABS Supplies? - 17 years ago
I've drilled my barrels to 1/8" as well, so the McMaster stuff should work. I figured I'd try 1 lb first and, if that seemed to work well, scale up.by degroof - Plastic Extruder Working Group
Re: Possible cheap feedstock: grocery bags - 17 years ago
There's another instructable here that shows how to make yarn/rope out of plastic bags. I wonder if that could be used as feedstock.by degroof - General
Re: ABS Supplies? - 17 years ago
brendanjerwin mentioned that McMaster has ABS welding rod. Sure enough, they have two colors in 1, 5, 10 and 15 lb coils. It's 1/8" diameter (3.175mm), which should be OK. I ordered a 1 lb coil (part # 7889A85) to see what it's like.by degroof - Plastic Extruder Working Group
Re: Possible cheap feedstock: grocery bags - 17 years ago
That's about right 1-2 kg for printed parts. I think I worked out that a year's worth of grocery shopping would net me enough to build one set of parts.by degroof - General
Re: Possible cheap feedstock: grocery bags - 17 years ago
I've melted grocery bags in the oven, using a baking dish. Takes quite a few bags to make a decent amount of plastic.by degroof - General
Re: No Computers Attached!!! - 17 years ago
For $100, you could add one of these:by degroof - Controllers
Re: No Computers Attached!!! - 17 years ago
SOI Sentinel Wrote: ------------------------------------------------------- > There's been up and down talk of > building a pseudo SRAM 16MB module over on > Sparkfun out of a CPLD and a SDRAM chip onto a DIP > carrier, but there wasn't enough interest. Too bad. I really could've used something like that a few years ago. I had implemented a stripped-down FAT16 CF interface in a 16Fby degroof - Controllers
Re: No Computers Attached!!! - 17 years ago
The main advantage of an SD card over an EEPROM chip is that the card usually has some sort of "wear leveling" algorithm to prevent any single memory location from failing due to excessive write cycles. In this situation, though, it's unlikely you'd ever run into that problem. Too bad no one makes SPI static RAM. They'd be really handy for a lot of different microcontroller projects. Any estimaby degroof - Controllers
Re: Gen 1 electronics problem: low extruder heating + firmware build fails - 17 years ago
I had a lot of difficulty with HDPE too. The only way I found to get around that high-temperature cut-off problem was to switch to a 100k thermistor. I also had problems keeping the nichrome soldered. Ended up using screw terminals instead. For the PTFE barrel slippage, I used wood screws through the top end and a hose clamp on the bottom end. Not sure who came up with that but I know a lot ofby degroof - Controllers
Re: Gen 1 electronics problem: low extruder heating + firmware build fails - 17 years ago
A reading of -273 could indicate a really small thermistor resistance (e.g. a short or near-short) or it could be that c3 is open or too small.by degroof - Controllers
Re: Gen 1 electronics problem: low extruder heating + firmware build fails - 17 years ago
If I recall correctly, the Gen 1 firmware has an auto-cutoff based on the extrusion temperature. It's supposed to prevent overheating but I've seen it do some odd things before. What's the value of your Extruder0_ExtrusionTemp setting?by degroof - Controllers
Re: Real Value - 17 years ago
The replicators on Star Trek couldn't replicate themselves (for some complicated, poorly-explained and convenient reason). The closest they came to that was the Exocomp, which had built-in replicators to create tools as needed. Chaos ensues when it's discovered that their replication technology has caused the Exocomps to become sentient. But, in typical Star Trek fashion, it's all resolved in theby degroof - General
Re: Real Value - 17 years ago
It's all academic anyway. The robots will've taken over long before we get to that point. The only thing we can hope for is that they don't sound like Arnold Schwarzenegger.by degroof - General
Maker Faire - 17 years ago
Maker Faire is this weekend. Anyone know if RepRap is being represented there?by degroof - General
Re: Real Value - 17 years ago
Here's some fun figures. Take an acre of land and work out the amount of energy produced with a) beef b) solar panels. Hope I got the numbers right... Beef ==== 1 acre will support 1 cow lifetime of cow is 2 years 1 cow yields 500lb of beef 1 lb of beef yields 600 kcal of energy Annual energy output = 500 x 600 / 2 = 150000 kcal per year = 627.6 megajoules per year Solar panel =========== 200Wby degroof - General
Re: SketchUp - 17 years ago
I just found this: There's something on there called SU2STL, which appears to export STL from Sketchup.by degroof - RepRap Host
Re: Real Value - 17 years ago
Yeah. Solar panels would be almost useless on my roof. Too much shade. F@$#*ing trees. :-)by degroof - General
Real Value - 17 years ago
This thread got me thinking about what actually has value. Imagine some future world where nanotech is ubiquitous. What would be worth anything? It really comes down to three commodities: matter, energy and information. Now, matter's easy, you can't turn around without bumping into it. I can go into my back yard and scoop up a handful of carbon, hydrogen, oxygen, nitrogen, silicon, aluminum, suby degroof - General
Re: Poor economics on front page? - 17 years ago
I was just reading this article: According to the article, Maurice Bloch says that humans are unique because only our brains are wired to imagine things that don't physically exist. The article talks about this in terms of religion but it could also refer to any intangible concept: justice, rule of law, artistic merit, consumer confidence, monetary value. I'm not sure I agree that this abilitby degroof - General
Re: DorkBot DC - 17 years ago
I read about this on the Make: blog. There was also something about Bruce Wattendorf doing a demo in Providence sometime soon.by degroof - Reprappers
Re: Cheap Laboratory Liquid Handling - 17 years ago
Yeah, a cheap cartesian robot would have a lot of uses in a lab environment, especially if it's easy to program. I could see the extruder head being replaced with a pipette manipulator. You'd probably be able to keep most of the electronics as-is and just reprogram the PIC / Arduino and write some new host software. One idea I have kicking around in the back of my head is to develop a paint headby degroof - General
Re: Support material candidates - 17 years ago
I think someone had tried cake frosting at one point.by degroof - Plastic Extruder Working Group