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Meet the Robisons and Their Low-Cost RepRap Kit (Video)

Roblimo posted about 2 years ago | from the today-3D-tomorrow-4D-with-5D-the-day-after dept.

Printer 67

It seems like less than an hour since Slashdot ran a Report From HOPE: The State of Community Fabrication. Now we have a video about a Massachusetts mother and son team we met at HOPE that had so much trouble with commercial RepRap machines that they designed their own and started marketing it under the name Robison Industries, a company they seem to be starting on the fly that uses their local hackerspace as its manufacturing location. Interested in RepRap? Maybe not yet, but as devotees of the concept point out, nobody outside a small circle of geeks was interested in personal computers at first, but they're ubiquitous today. Will we all have 3D printers on our desks in a few years? Good question. round us up in 2020 or 2025 at our local hackerspace and we may have an answer for you.

For those interesting in further reading, a selection of links mentioned in the video:

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Bender says (3, Funny)

Guano_Jim (157555) | about 2 years ago | (#40701643)

Fine, I'm gonna make my own 3D printer! With blackjack! And hookers!

In fact, forget the 3D printer.

Well let me be the first to say: (0)

Anonymous Coward | about 2 years ago | (#40701673)

And here’s to you, Mrs. Robison,
Jesus loves you more than you will know

What's the cost of these things? (1)

acidfast7 (551610) | about 2 years ago | (#40701743)

For the initial RepRap it seems to be about 350€ of material? Which, to me seems quite OK (especially when 70€ of that is VAT.)

from here: http://reprap.org/wiki/About [reprap.org]

What am I missing?

Re:What's the cost of these things? (1)

gl4ss (559668) | about 2 years ago | (#40702659)

a place to order?

seriously, could someone hook me up with a reprap, makerbot replicator etc to order within eu with shipping to finland? I got money to burn on one but finding out a reputable place that has stock seems hard?

Re:What's the cost of these things? (0)

Anonymous Coward | about 2 years ago | (#40705437)

Got mine from reprappro.com Run by the Bowyers (reprap conceiver). They're based in the UK and ship worldwide (i think).

So what else is new? (0)

Anonymous Coward | about 2 years ago | (#40701753)

Since when does Slashdot post every new RepRap kit to come out? At least 10 new SKUs have come out in the last year, each from a different brand new company, and many with real manufacturing rather than Hackerspace assembly....

Whats special about this?

Re:So what else is new? (1)

crazyjj (2598719) | about 2 years ago | (#40701909)

They just wanted an excuse to use the term "hackerspace" in yet another article.

Re:So what else is new? (1)

acidfast7 (551610) | about 2 years ago | (#40701943)

Trendy = bad.

Alone, the voices of the people in the video, make me never want to visit a "HackerSpace."

Re:So what else is new? (0)

Anonymous Coward | about 2 years ago | (#40702095)

And it's likely you wouldn't fit in there because you're put off by something like that. So it's excellent that you'll never visit one :)

Innovators, inventors, thinkers, creators, etc. really wouldn't enjoy your presence in the least.

Re:So what else is new? (1)

acidfast7 (551610) | about 2 years ago | (#40702237)

Lol ... I run a research group which is extremely creative :P

Re:So what else is new? (1)

crazyjj (2598719) | about 2 years ago | (#40702293)

Yeah man, you're obviously not hip enough to hang out in our record store. You probably don't even listen to vinyl.

This is really dire. (4, Funny)

kotku (249450) | about 2 years ago | (#40701775)

All the product designers and manufacturers of real products are going to have their products stolen and made by freeloaders at home. It will be the total and irreversible end of creativity and innovation. It must be stopped.

Re:This is really dire. (0)

Anonymous Coward | about 2 years ago | (#40701877)

Er... This is meant as a joke, right?
Creativity and innovation for everyone instead of in the hands of a few people, does that pose a problem to you?
Or maybe you're the kind of person who prefers mainframes to personal computers? Dictatorship to democracy?

Re:This is really dire. (0)

Anonymous Coward | about 2 years ago | (#40701959)

I modded it funny and so did 4 other people. Either our humor detectors are broken or it's a joke.

Re:This is really dire. (1)

acidfast7 (551610) | about 2 years ago | (#40701911)

Which will, in turn, force a return to the classics, which is nice.

Stuff that can't be made easily.

Take Eames chairs made out of molded plywood. They're classic, they're comfortable and that can't be made/imitated that easily.

Re:This is really dire. (2)

sgrover (1167171) | about 2 years ago | (#40702067)

Sure, one *could* create a model and then print something that is commercially available. What really happens though is that people create the parts that they need that the commercial entities are not selling. Like a broken plastic piece to a cargo area cover. The vendor's solution is to spend the $500ish on a new cargo area cover. The printer owner's solution is to create a model and print out $0.30 worth of plastic to fix the existing cover. In this sense, the vendor's game has to change, or at least recognize the fact that they are not servicing their customers - they are only pushing product. (the irony is that it took a $500 - $2000 printer to make that 30 cent part, to save the $500ish. but the printer can be used for more than just that one job).

At the moment, 3D Printing tends to be focusing on "cool trinkets", but I'm seeing a gradual shift to practical items too. Those are boring though so don't get as much attention.

Re:This is really dire. (1)

Anachragnome (1008495) | about 2 years ago | (#40703725)

"At the moment, 3D Printing tends to be focusing on "cool trinkets", but I'm seeing a gradual shift to practical items too. "

How about making 3D printer parts?

Re:This is really dire. (1)

sgrover (1167171) | about 2 years ago | (#40703819)

3D Printer parts falls under both categories. Or collectively as "cool practical trinkets".

Re:This is really dire. (0)

Anonymous Coward | about 2 years ago | (#40717083)

The name RepRap comes from "replicating rapid prototyper." From the very beginning of the project, it was designed to print its own parts.

Re:This is really dire. (1)

iphinome (810750) | about 2 years ago | (#40708729)

Someone needs to 3d model some sewing machine feet. Small, useful (to people who sew), not always easy to find. And the little plastic scissor parts in notebook keyboards, the little guns and swords kids lose form their action figures, crochet hooks.....

I really should take the time to learn one of the many 3d modeling programs out there.

Re:This is really dire. (1)

Joce640k (829181) | about 2 years ago | (#40702171)

I doubt a 3D printer can achieve the economies of scale of traditional molding of plastic parts. There's also going to be a lot of parts which simply cannot be printed, eg. motors, heating elements, etc. You also have to factor in the construction times. Not everybody lives in a basement and has ten hours a day free for hacking about (I wish I did!)

In short, commercial producers will always have an edge over home made.

Re:This is really dire. (1)

Anomalyst (742352) | about 2 years ago | (#40703065)

It will excel at making that $111.00 plastic part from the dealer for your car with an expenditure of a little effort and a couple bucks of feed stock. Just cuz it was cheap to make thousands at a crack a couple years ago doesn't mean that those savings are will be passed on to the consumer.

Re:This is really dire. (1)

Joce640k (829181) | about 2 years ago | (#40709253)

If that ever happens the car manufacturers will counter with parts that are more difficult to reproduce.

Re:This is really dire. (2)

Sentrion (964745) | about 2 years ago | (#40703781)

Obviously even the best and most advanced yet affordable 3D printers won't mean that people could just print out every product they ever needed. But even in our mass-produced world, final production of many products is just a process of assembling - by hand - several stamped, machined, forged, or molded components. The possibility that I could mold many of my own components, and the possibility that I could download and upload drawings, designs, instructions, and codes to print such components could help keep manufacturer's prices in check.

As some other post have already pointed out, this type of technology could help DIY-minded people fix their own products rather than replace them or spend exorbitant amounts of money of spare parts. One of the best uses for 3D printers is for aspiring inventors to build prototypes and cheaply test their designs. The machines could definitely be handy for those living in remote parts of the world where having just the right type of plastic part produced on-site very quickly can fix a problem that otherwise would be a really hassle to deal with. A cheap 3D printer, a $100 laptop, wireless internet access, and on-site renewable power generation - can you see what these types of technologies could possibly offer for people living in developing countries? Factor in the latest advancements in sustainable agricultural and architectural practices and the 3rd world may end up being the envy of the developed world after we reach peak oil.

I think there could be a "threat" to commercial producers in the future if these trends continue. More "Open" sharing of information, technology, media, and code. Online collaboration of like-minded consumer-producers, the advantage of extreme customization possible with printing your own products, the proliferation of hackerspaces, and the possibility that intelligent robotics could be developed to make more desktop fabrication possible. Imagine a pair of robotic arms with articulated hands that could assemble more complex products. There are a lot of hobbyists experimenting with all sorts of manufacturing technologies, from traditional blacksmithing all the way to growing crystals in precision controlled pressure furnaces.

Mass production means that the cost of production decreases per unit, but that doesn't stop companies from charging 10 or 20 times that amount when competition is light and their customers aren't used to making a similar product of their own. And how often is it that the mass-produced item just isn't designed the way you would have preferred or the quality is substandard - below what you could have done on your own? More 3D printers and similar rapid prototyping technologies in homes, offices, and small businesses would force the mass producers to increase their quality, lower their price, offer better designs, and ways to customize their products to the specific needs of their customers. Everybody wins (except Wall Street).

P. S. Ultimately, if humans are going to live sustainably and independently in environments like the Moon, and especially Mars, such small-scale highly flexible and customizable fabrication technology will be required.

This is right (1)

DaKong (150846) | about 2 years ago | (#40713385)

except when it becomes as easy for people to toss broken objects into a hopper and see them reconstituted as a complete object. We are conditioned by traditional manufacturing techniques to regard objects as *finished,* ie. they cannot be changed after purchase. But if you fast-forward to a 3-D printing universe, then all those assumptions are undone.

We are talking about a future in which you can toss a "finished" product into a 3-D printer hopper and have it outputted to a customized form thanks to a downloaded mod. The mass & volume of determinant materials is the only limiting factor. But if you can provide those feedstocks yourself, then all bets are off.

We are entering an interesting time of transition. Trained industrial designers and engineers who work for centralised conglomerates find themselves suddenly thrust into a world where anything is possible.

It is a paradigm shift. Humanity can take a quantum leap into the future, or fall back into the dark ages to protect status quo interests. I await the outcome.

Re:This is really dire. (1)

Atrox666 (957601) | about 2 years ago | (#40702533)

Hurry the hell up I wanna download a car.

Re:This is really dire. (1)

tlhIngan (30335) | about 2 years ago | (#40715021)

All the product designers and manufacturers of real products are going to have their products stolen and made by freeloaders at home. It will be the total and irreversible end of creativity and innovation. It must be stopped.

You laugh, but DMCA takedowns have already happened [arstechnica.com] to sites hosting 3D shape files.

Many of these community sites aren't actually ready to handle stuff like this, either.

Not sure about the name... (0)

pathological liar (659969) | about 2 years ago | (#40702083)

What are their users? Reprapers? Reprapists?

Re: Not sure about the name... (0)

Anonymous Coward | about 2 years ago | (#40702597)

RepRappers, duh. Gold chains and track suits optional.

Re: Not sure about the name... (2)

Sentrion (964745) | about 2 years ago | (#40703839)

Yes, RepRappers is the proper term. A RepRapist is one who uses a RepRap without consent.

When (if ever) will prices come down? (1)

JDG1980 (2438906) | about 2 years ago | (#40702269)

I'd be more interested in 3D printers if they didn't cost $500+ for even the cheapest models. Even DIY kits are several hundred dollars. I think they'd be much more likely to catch on if they started in the $100-$200 impulse buy range.

Re:When (if ever) will prices come down? (4, Informative)

couchslug (175151) | about 2 years ago | (#40702699)

Five hundred bucks IS in the "impulse buy" range for many consumer goods.

A hundred or two hundred bucks nowadays won't get you many tools of any sort.

Re:When (if ever) will prices come down? (2)

drinkypoo (153816) | about 2 years ago | (#40703029)

Five hundred bucks IS in the "impulse buy" range for many consumer goods.

Sure, if you've got money pouring out of your asshole. It's also half a month's rent, or a couple car payments, or a mortgage payment if you don't have a fat, short mortgage. Shit, I could get a functional used car for that around here. That's a lot of money for an impulse buy. Whether it's a lot of money for a 3d printer is a separate issue.

Five hundred bucks will get you a pretty decent auto scan tool. Five hundred bucks will get you a great used lathe. Five hundred bucks is enough to buy an old, sloppy milling machine that needs some parts you can make on that lathe. Five hundred bucks, as it turns out, is actually quite a bit of money.

Re:When (if ever) will prices come down? (1)

thesandtiger (819476) | about 2 years ago | (#40703709)

So save your pennies and instead head off to a maker space or other shared tool environment and get out of the benefit at a cost lower than $500 bucks.

Hell, even if you can afford it, spend money at a maker space. I can fairly easily afford to buy some expensive kit on only a bit more than a whim, but by and large I don't because I don't feel that personally owning it would be worth the hassle, and I would much rather support a community space with my money because it means a LOT more people benefit from your spending, which means there's a lot more chances for interesting innovations to pop up.

Re:When (if ever) will prices come down? (3, Insightful)

thesandtiger (819476) | about 2 years ago | (#40703771)

$75 a month will get you monthly membership in most maker spaces actually.

Ever you are in a position where dropping $500 on a whim is feasible, in many cases you would get more bang for your buck and do a lot more benefit from supporting your local maker community, and helping people who have good ideas but not enough money themselves to buy tools to make those ideas happen. Everyone wins, and you can spend your money on other impulse stuff :D

Re:When (if ever) will prices come down? (3, Interesting)

TheCarp (96830) | about 2 years ago | (#40702911)

I paid over $900 for the kit I built mine from. Worth every penny if you ask me. In fact, I am already seeing the benefits of rapid design. I went from having never done any sort of 3d modeling or design apart from with hand tools to making my own custom parts pretty quick.

More than that, its the rapid prototyping that ROCKS. Its not just that I can design a part and have it made. I always could do that if I wanted to spend the money...but I can design it... print it (in whole or part) and see the results in minutes or hours not days or weeks. Just last night I stopped a print after 20 minutes because the entire subpart I needed to test was done enough for my purposes.

I can go through 4-5 design iterations in 1 night with design features that would have otherwise required special equipment and more time. I can print out threaded parts, with no need to tap or turn them.

A bit much for an impulse buy, but, do you really think a tool like this is the sort of thing you should impulse buy? They are really amazing tools, and limited mostly by your imagination.

That said, they take time to learn how to use effectively, and a fair amount of manual tinkering. Want one that doesn't? Expect to pay ALOT more...and even then... a friend of mine has a professional model where he works. Its not that it takes no tinkering, its just that, at the price they pay for it, its worth it to pay some guy to come out and do the tinkering for you.

getting it down to that range, I am not going to say is a bad thing, but, it just means there will be more of them, sitting in boxes, collecting dust, and otherwise, in the posession of people who played with them for a week and then lost interest....

True it would put them, faster, into the hands of those who really want them and will use them but can't afford one right now, but, what will you be putting in their hands for that price?

All that said, there is a CNC milling machine the Mantis-9 that could be realized somewhere in that price range (havn't priced out the electronics, but the non-electronic hardware is $100... another $100-200 for electronics depending on the options, though possibly less)

With that you can mill PCB to make custom circuit boards.... with the same benefits... rapid prototyping.

Will I make end final parts on it? Sure, why not? Already do, already printed a nice little figurine for the wife (Crest of Hyrule!)... but...its real win is in rapid prototyping.

Re:When (if ever) will prices come down? (1)

Applekid (993327) | about 2 years ago | (#40703607)

getting it down to that range, I am not going to say is a bad thing, but, it just means there will be more of them, sitting in boxes, collecting dust, and otherwise, in the posession of people who played with them for a week and then lost interest....

That would actually be great: you don't really see a lot of second-hand 3D printers on the market!

Re:When (if ever) will prices come down? (1)

Applekid (993327) | about 2 years ago | (#40703537)

Of course they'd catch on better if they were cheaper. If you had 1 cent beers you'd have a lot of takers, too. :)

As far as hobbies go, there are far more expensive ones than 3d printing. But I can imagine it's hard to be convinced to take the plunge if no one around you already has.

"seems like"? (1)

Chas (5144) | about 2 years ago | (#40702311)

Seems like less than an hour

Posted by Unknown Lamer on 12:30 PM July 19th, 2012
from the car-piracy-for-fun-and-profit dept.

Posted by Roblimo on 12:48 PM July 19th, 2012
from the today-3D-tomorrow-4D-with-5D-the-day-after dept.

I dunno Rob. To me that *IS* less than an hour. Hell, it's 18 minutes.

Why not try for a bit of accuracy in your pseudojournalism?

Low cost FapFap kit? (0)

Anonymous Coward | about 2 years ago | (#40702377)

Count me in!

Seriously... (0)

Anonymous Coward | about 2 years ago | (#40702477)

that guy needs to move his ass out of his moms basement and get a girlfriend..

Trusting Trust (1)

devnullkac (223246) | about 2 years ago | (#40702915)

Do RepRap machines, as open as they are, suffer from Ken Thompson's Trusting Trust [bell-labs.com] problem? I suppose once the integration is sophisticated enough to incorporate the controller software in the replication process that it could, for example, recognize any tumbler-style lock device being printed and surreptitiously modify the design during printing to include support for a special master key. Is there a lower-level analog to the compiler problem that involves only subtle changes to the hardware elements?

Re:Trusting Trust (1)

vik (17857) | about 2 years ago | (#40707489)

Good luck writing that software.

Low cost? (0)

Anonymous Coward | about 2 years ago | (#40703031)

So, they'll sell you a kit for $650, when you can self source for $450? WHAT A DEAL! IS SO LOW COST!

Who'd they blow to get this slashvertisement?

Older unit (2)

romco (61131) | about 2 years ago | (#40703091)

I have a reprap on my desk. Last week I printed an adaptor for a new ssd harddrive and and couple of mike clips. I use it all the time. Cost me ~$500 to build and about a weeks tinkering to get it right. I could get one tweeked in a day or less now.

I dont recommend buying a built one as they are still at the model "T" stage and require a lot of tinkering to get them going. If you build it all the tinkering will make sense.

In the video they have a original mendel.
http://reprap.org/wiki/Mendel [reprap.org]

  If you are starting out I recommend a Prusa Mendel, cheaper and better.
http://www.youtube.com/watch?v=B3D56IpACME [youtube.com]

your first step is to go to IRC and look up #reprap in Freenode and talk to the people in the room. Its not uncommon to find the very people who are designing these (Like Mr. Prusa) in the room.

As low as USD 300 ... (0)

Anonymous Coward | about 2 years ago | (#40703203)

RepRaps are going as low as USD 300 for the parts (all included): http://www.3ders.org/pricecompare/3dprinters/

Re:As low as USD 300 ... (1)

bluefoxlucid (723572) | about 2 years ago | (#40711873)

The cheapest thing there is $320USD and the cheapest RepRap thing there is $499USD.

No lady, you're wrong. (1)

mapuche (41699) | about 2 years ago | (#40703753)

Everybody has a computer nowadays, but no everyone writes a Linux. Not everyone will be creating stuff in 30 years with a printer.

im all for buzzwords but seriously (1)

nimbius (983462) | about 2 years ago | (#40704033)

what the fuck is a reprap aside from just one more attempt to sneak another makerbot story into slashdot

Re:im all for buzzwords but seriously (1)

sixtyeight (844265) | about 2 years ago | (#40705213)

RepRap is the only fabber of which I'm aware that can print much of the pieces necessary to build another instance of itself.

Sneaking a personal fabber story onto Slashdot? That would seem to be like sneaking a piece about an upcoming astronomic event onto NASA's page. Why the beef?

Er, Makerbot is a RepRap derivative.. (1)

vik (17857) | about 2 years ago | (#40707501)

Reprap came first, mate. Makerbot is a spinoff from one of the core members which has now been taken over.

Look me in the Eye (1)

Registered Coward v2 (447531) | about 2 years ago | (#40704767)

I believe the guy showing off the guitar is John Elder Robison, author of "Look me in the Eye" and brother of the author of "Running with Scissors." I highly recommend Look me in the Eye; not only for it's stories of being a roadie for the band but it's look into life with Aspergers.

Re:Look me in the Eye (0)

Anonymous Coward | about 2 years ago | (#40705747)

Is that why this story is tagged "Autism?" Cause that is a weird ass tag.

Simple answer to question in TFS (1)

DragonWriter (970822) | about 2 years ago | (#40705215)

Will we all have 3D printers on our desks in a few years? Good question. round us up in 2020 or 2025 at our local hackerspace and we may have an answer for you.

If by "2020 or 2025" you still have to round people up at a "local hackerspace" to get information on the how who is using 3D printers, the answer to the question posed in the first sentence is "No."

Meet them??? (1)

mark-t (151149) | about 2 years ago | (#40706535)

I thought they were Lost in Space [imdb.com] . And, as I recall, the series never did come to any sort of adequate closure.

Anybody working on a more comprehensive one? (1)

mattr (78516) | about 2 years ago | (#40707009)

A post on recent /. thread said: "RepRaps can make only a tiny fraction of the parts needed to build another RepRap. They can't build transistors, microcontrollers, capacitors, stepper motors, wire, and so forth."

So I am just wondering is anybody working on an open source system that really can do all that? I guess it works like this:
stage 1 replicator - means it makes some limited number of parts, you assemble
stage 2 replicator - requires you provide a supply of special parts to the machine, and it assembles a final product making what it can.
stage 3 replicator - it makes everything from scratch (raw materials) and it assembles.

Re:Anybody working on a more comprehensive one? (1)

vik (17857) | about 2 years ago | (#40707513)

So, seeing as the human body needs to ingest roughly 35% of its essential substances because it can't make them, where do humans fit on your scale?

Re:Anybody working on a more comprehensive one? (1)

mattr (78516) | about 2 years ago | (#40710787)

This wasn't a deeply thought proposed scale and the writing is vague, sorry.
The stage 3 I suggested above means that the assembler takes in raw materials, in other words no preassembled parts.
I was imagining a bunch of racks that can hold simple motors, switches, ic chips and other complex parts that a stage 2 replicator would be able to automatically select and assemble into the finished product.
For biological systems of course there is a gray area between stage 2 and stage 3, depending on if you consider for example vegetable protein a complex preassembled part. Apparently humans must ingest protein to survive, I just googled a little. Still I would lean toward calling humans stage 3 assemblers since for a few reasons:
- humans I think take apart everything they ingest and rebuild from molecules up. So amino acids are raw materials.
- humans can build the most complex parts, like an eye, a knee or a brain without needing to ingest eyes, knees or brains.
- humans actually have inside them nanoscale programmed molecular assemblers so even if you don't accept human as stage 3 assemblers because proteins are complex, they contain stage 3 assemblers themselves. I'm thinking of cellular nuclei, ribosomes, etc.

Re:Anybody working on a more comprehensive one? (0)

Anonymous Coward | about 2 years ago | (#40720015)

They actually call stuff they cannot print 'vitamins'(http://reprap.org/wiki/Vitamin) and sometimes even call it a symbiosis between the human who gets the plastic, energy, and vitamins (...and code and designs...) and the reprap which makes the stuff. Wording stretched a bit.(They don't really use the term symbiosis)

Re:Anybody working on a more comprehensive one? (1)

Anonymous Coward | about 2 years ago | (#40709139)

Yes(well kinda), though they're going a little beyond rep-raps...

http://opensourceecology.org/

Re:Anybody working on a more comprehensive one? (1)

mattr (78516) | about 2 years ago | (#40710797)

Thank you very much, that is cool!

Re:Anybody working on a more comprehensive one? (1)

bluefoxlucid (723572) | about 2 years ago | (#40711925)

Irrelevant at this stage. What we need first is better support for plastic. I want a hopper that re-extrudes spent ABS into fresh filament.

Re:Anybody working on a more comprehensive one? (1)

Applekid (993327) | about 2 years ago | (#40712189)

Irrelevant at this stage. What we need first is better support for plastic. I want a hopper that re-extrudes spent ABS into fresh filament.

Filabot.com [filabot.com] is your bag, then. Right now it's only making filament from granules, though. Even with a grinder, they're going to have to deal with needing the re-addition of volatile chemicals that are currently lost during printing.

As far as plastics, there is loads of work being done. PLA (biodegradeable polymer), PVA (water soluble), Polycarbonate, even Nylon are successfully being extruded and printed.

Re:Anybody working on a more comprehensive one? (1)

bluefoxlucid (723572) | about 2 years ago | (#40716565)

PLA is plant-derived, I don't know if it's biodegradable. It's also a bad idea to mix PLA into recyclable plastics, so PLA becomes non-recyclable and can taint recyclable petrol plastic stock. Mind you a mass shift to PLA would be ideal, but we'd need a PLA compatible alternative to ABS; ABS has much better physical properties than PLA. Plastic parts aren't all inferior to the task--ABS can hold up to significant heat and force, which makes it an attractive replacement to metal in some situations. Obviously no piston heads or crank shafts for V8 big blocks, but hinges and fasteners and gears of ABS in many applications can hold up far better than is needed for a long life--similar to how exotic steel superalloys are used in turbochargers, but not necessary for bicycle frames.

Acetone can melt PLA and ABS, but so can heat. What we need is a heat-driven source pot and extruder. Ideally you would want a funnel pot attached to a valve going directly into the cooled extrusion head (no tubing run). The valve is heated, it goes into a short (1cm or less) steel tube (also heated) that serves simply to junction it to the extruder, which is itself cooled. After being filled with material, the pot is sealed and heated. Air is pumped into the pot to pressurize it when extrusion is to begin. Before the pot empties, it can be depressurized and additional material introduced.

Such a process has the problem that extruded plastic must flow at a continuous rate or weaknesses can occur in the produced filament. A two-pot process may suffice, by which the first pot is connected to a second pot. The second pot, the tubing run from it, and the valve controlling it are all heated. Additional feed stock is melted in the second pot; once melted, the pressure in the first pot is maintained by pushing melted feed stock into it from the second pot (by pressurizing it and releasing air pressure from the first pot, of course). Volume of pressurized air is decreased in the first pot more rapidly than volume of molten feed stock, replaced with more molten feed stock to maintain the pressure. Desired pressure is strictly maintained in the second pot, such that depressurizing the first pot draws in more molten feed stock rapidly to equalize the pressure. When the second pot is low, the valve closes and pressure is maintained in the first pot. This adds feed stock to be extruded without interrupting the constant flow rate; and with the second pot now decoupled, we can release pressure and add a measure of fresh solid feed stock from a hopper, melting it down to replenish the molten stock for extrusion.

It's a complex machine. You can't just melt stuff and expect the extruder to work. The extruder on a reprap supplies pressure by mechanically feeding a filament through a hot extruder. We're supplying molten liquid and trying to get a controlled, flexible filament out, so constant feed pressure has to be maintained and the filament has to follow a constant cooling gradient (it has to shift from hot to cool along its mass such that the area that's solidified flows gently into the area that's hot, facilitating smooth welding--a homogenous polymer filament, rather than a heterogenious mess of either weak or hardened fusion joints). It can't be allowed to drip or spread. It's tough to do all this; the best way is to take a bag of hot material and start squeezing it through a cone with a hole at the end to cool it. That's ridiculous and won't work.

Tagged autism?? Seriously? (0)

Anonymous Coward | about 2 years ago | (#40707581)

WTF, Slashdot? My nephew is autistic. Shit's not funny.

(But my captcha is "raging", which kind is.)

Massive Heaps Of Plastic (0)

Anonymous Coward | about 2 years ago | (#40708453)

in landfills. Yes, 3D printers are cool, but the price is going to be higher than anyone is talking about right now.

Wow (0)

Anonymous Coward | about 2 years ago | (#40713859)

I feel sorry for that kid who knows so much and his mom who knows so little. She's like a stage mom who wants to be part of the show. Notice how she is completely bored and ready to snatch the mic out of her sons hand while he is actually talking about useful information and sounding like he knows what he is talking about.

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