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General discussions. For specific printers / electronics / fabrication methods / softwares, please see other sections.
Re: RepRap Silicon! - 16 years ago
A nice idea. What do you know about doping? I have daydreamed of a similar system since around age 15, so I, for one, am rooting for it.by Roach_S - General
Re: The Canon - 16 years ago
Robert, If you have that accuracy, and can keep it in an arm, then you could put that arm on a larger arm for course positioning. However, I suspect that if you're going to move single atoms around, and assuming the individual armature can move and place one carbon atom a second, you'd need about 6022 * 10^20 units ganged together to output 12 grams of carbon per second.by Roach_S - General
Re: Building CNC machines from Epoxy+Granite - 16 years ago
At the practical limit, assuming the darwin printing space is a cube, ((1+1)^.5)+1)^.5 = 1.553774 The darwin, assuming it could print everything, including the rods, could print the parts of a unit up to 1.5 times the dimension of the printing volume. Rods, being the most difficult, would be printed at a diagonal.by Roach_S - Casting and Moldmaking Working Group
Re: Neil Gershenfeld: The beckoning promise of personal fabrication - 16 years ago
I agree with you, with one reservation. Manufactured goods are faster to assemble. Consider the length of time it takes a printer, that is a printing press, to produce one book. Compare that to the length of time it takes a desktop printer, even a fast laser printer, to produce all the pages of one book. In your factory, having a number of repraps is still potentially slower than having a lineby Roach_S - General
Re: The Canon - 16 years ago
Probably until we let someone else tell us what is acceptable for us to read again. Or worse, what is acceptable for us to write again.by Roach_S - General
Re: The Canon - 16 years ago
Hmm. It's been awhile since I read Snow Crash, but I remember the, appropriately named, protagonist using his machine and thinking about how good it was. His ex-girlfriend, using a payphone was at an advantage. She could see every nuance of him, and he was stuck viewing a poor pixelated image of her. Also, bandwidth goes both ways. Oh, I enjoyed the books, I just got caught by the technical deby Roach_S - General
Re: Neil Gershenfeld: The beckoning promise of personal fabrication - 16 years ago
Thank you.by Roach_S - General
Re: The Canon - 16 years ago
Having read Snow Crash...I generally don't consider Neil Stephenson to be "technically informed". The bandwidth of the operator determined the complexity of the avatar, not the bandwidth or processing power of the viewing machine. Also, I'm a bit skeptical about his concept of nanotech computers. His "Diamond Age" computers read as Babbage engines, complete with moving parts. Perhaps that isby Roach_S - General
Re: Neil Gershenfeld: The beckoning promise of personal fabrication - 16 years ago
I checked the link. Is there a particular order to get the books? I would guess the foundry is first, but is there a necessary second? What books have other books as prerequisites, and what are those prerequisites? Dropping $60 on all the books isn't something I can justify, especially as the difference between the package deal and the individual books is somewhat less than half the price ofby Roach_S - General
Re: Journal Club! - 16 years ago
Hmm... Slightly off the topic, but your writeup suggests, to me, interlacing as a possible component in getting the shrinkage issue under control.by Roach_S - General
Re: Building CNC machines from Epoxy+Granite - 16 years ago
For starters...are you related to anyone from Oklahoma?by Roach_S - Casting and Moldmaking Working Group
Re: The Canon - 16 years ago
The way I see it, it's already happened, medical modification impacting survivability, that is. I wear glasses because I'm nearsighted. My mom wears glasses because she's VERY nearsighted. I wear clothes because both of my parents are practically bald from the neck down, and this environment, not to mention the social vagaries that have arisen around them, are not conducive to nudity. I don'tby Roach_S - General
Re: A worked Servomotor example - 16 years ago
Something I thought of, but am not able to experiment on, would be using cheap magnetic tape, along with a gang of crudely placed magnetic sensors, for position measurement. If you can get your hands on a couple pieces of magnetic tape, attach them together then drag them apart. The way the stuff is made seems like it'd be a nice "optical stripe" for a magnetic sensor. Throw in enough, not perby Roach_S - Mechanics
Re: Objects.RepRap.Org - Any volunteers? Let's build a file library! - 16 years ago
One advantage of staying with a wiki, especially mediawiki, but with stricter editing and authoring criteria, would be you could probably use the existing pages without conversion or alteration. I'd say go with captcha of some form, along with an occasional review, by trusted editors, to kill those accounts that slip in anyway. From the last days of editing, I noticed the early posts of spammersby Roach_S - Administration, Announcements, Policy
Re: Inconsistent actualisation of the posts ... - 16 years ago
...even if you visit a forum for the first time as a visitor. Actually, I thought this was a feature to help you track the forums you followed, without cluttering it up with notes on the ones you didn't.by Roach_S - Administration, Announcements, Policy
Re: Printing working 3D Body Parts already being done. - 16 years ago
You know. You could probably fire an ice cube from a steam cannon, if you didn't leave both in the breach for too long.by Roach_S - Tissue Engineering
Re: Printing working 3D Body Parts already being done. - 16 years ago
I'd be a bit concerned about prions when eating reprapped long-pig. As for the sampling. If you're reproducing a lost limb, or other organ, theoretically, you could tease apart the mangled one for the culture samples to use. And as for what rights you assign a "lab grown animal brain" in a homing missile...the right to fulfill its purpose. As far as rejection. If they're your own cells, or cuby Roach_S - Tissue Engineering
Re: Cricut Automatic Paper Cutter - Hackable? - 16 years ago
I hope you unregistered individuals are using some anonymous proxies, or are safely outside the US jurisdiction. And considering what happened to the kid who wrote DeCSS, I'm not sure anyplace is such.by Roach_S - RepLab Working Group
Re: Extruder idea. - 16 years ago
And here I thought the differential was a french invention.by Roach_S - Mechanics
Re: Extruder idea. - 16 years ago
I could be wrong, but I thought the shrinkage was due to simple thermodynamics, not any property unique to polymers. That is, things expand when heated, and contract when cooled, water being a partial exception. It sounds to me like you're talking about squirting the plastic out in the direction of travel, and then driving the extruder head over it. You might want to see how some of the early eby Roach_S - Mechanics
Re: Printing working 3D Body Parts already being done. - 16 years ago
When they figure out how to interface it with the brain you have, which is trained to work four limbs. However... Perhaps not all that long after someone grows the first replacement limb.by Roach_S - Tissue Engineering
Re: Touch Sensor and automated calibration - 16 years ago
But...that'd be half the fun... If you're going to do that, it might actually be cheaper to attach a webcam and program the thing to see what it's doing, and recalibrate on the fly to compensate.by Roach_S - General
Re: Occam - 16 years ago
Are there any suitable epoxies? I'm thinking if you can silver epoxy in the same manner as glass, (it's important to remember glass is hydrophilic, so I don't know if you can,) you can use straight silver. As you're going to coat it immediately afterward, tarnish shouldn't be an issue. As for heat conductance. Yes, that's a likely problem. Whatever the components are place on, or in, needs tby Roach_S - General
Re: Occam - 16 years ago
Nah. You can use chemistry to deposit a layer of metal on something. An alternate approach to consider. Instead of using Surface Mount devices, use the more traditional leaded variety. Mount them back down, with the legs up, on flypaper, or a fitted tray, then pour your epoxy to cover the components, but not the leads. Shear off the leads where they protrude from the epoxy, wash, then plate thby Roach_S - General
Re: Cartensian Robot Designs (Pros and Cons) - 16 years ago
Temporarily mount a rod alongside the extruder in perpendicular, make sure the robot is plumb, then make sure the rod is. Do the same thing with a slide projector. Mount the rod so it hangs down in front of the arm, then project light on it, and check to be sure the rod shadows the arm down its length.by Roach_S - Mechanics
Re: Cartensian Robot Designs (Pros and Cons) - 16 years ago
I've not worked with either, so take my comments with the appropriate quantity of NaCl. You could align the head initially, hen drill both the mounting plate and the pipe it's attached to. Then thread the htole for a bolt, or just drop a cotterpin through, (actually, match the cotterpin and drillbit, so that you need a bit of force to get it through, or else use a conical hole, and a conical piby Roach_S - Mechanics
Re: Custom Circuitry - 16 years ago
I'm stalled on a project for church, (next warm weekend, I'm mixing some etchant, until then...) As a consequence, I've been thinking about something mentioned before. Etching PCB's with the McMaster. The originator of the design, if my memory and understanding of what I read is accurate, did some routering of circuit boards, but found that a small error in alignment caused him to cut the boardsby Roach_S - Mechanics
Re: Spam in the wiki? - 16 years ago
Yes, plus banning the existing spambot accounts. Moving the working directory might be easier.by Roach_S - General
Re: Spam in the wiki? - 16 years ago
Looks like someone decided to assault us. Only the opening salvos, yet. He added one nonsense word to the first line of 22 pages, at a rate of about two pages per minute. Can you move the wiki? Break a few links? I doubt these 'bots navigate via the homepage, or even the recent changes page as I do. More likely, they have the URL's of their target page softwired, so changing the URL's of theby Roach_S - General
Re: A madman with a blowtorch (problem soldering wire) - 16 years ago
Workable, but the gear needs to be smaller than the screw. Otherwise, it blocks the feedstock anyway. Since the driving gear needs to make up the difference, it means your screw drive motor will be significantly geared up. Alternately, you can use a belt between the two.by Roach_S - Reprappers