Have you ever dreamed of having one of those replicators from Star Trek? Ever wanted to make just about anything at the flip of a switch?

Well guess what? You're in luck, because in this Instructable I will show you how to make the closest thing to a replicator that current technology can manage; a 3D printer.

Wait a minute, isn't there another Instructable on how to make a 3D printer from Legos? Yep, there is, but this 3D printer is different; it's a polar 3D printer and it's capable of printing out so much more than just chocolate.

Now at this point in the intro you're probably thinking what do I mean by polar 3D-printer. Is it a 3D-printer that only works in the in the polar regions?

A polar printer is a printer whose principal axes, or how it can move, are radius(in and out), angle(spin clockwise/counter clockwise), and as opposed to a Cartesian printer whose principal axes are X(left/right), Y(up/down). In other words, it moves just like a polar coordinate system.

So why did I make a polar 3D printer instead of a good ol' Cartesian 3D printer?

1. I didn't have enough Legos to build a Cartesian printer.
2. I hope to eventually add a 3D laser scanner to it so I can scan in objects and send them to another printer somewhere else in world. Making sort of a 'teleporter'.

Before I begin this Instructable, I must remind you all of something; I have not yet finished developing control software for it.

Before you start posting variants of "This Instructable sucks" in the comments, I would like to remind you of something, the Altair 8800, the world's first successful personal computer, the computer that is the reason why you are able to read this Instructable and post derogatory comments, came with no control software either. But the Altair 8800 had prospects and it ignited a revolution. In fact, Bill Gates and some friends started Microsoft by writing software for the Altair.

I hope that this 3d printer will ignite the 3d printing revolution, so build one and join the revolution!!!

I would also like to thank the people at reprap.org for their help and support.

Cool!!!!! I've been wanting a 3-D printer!!!! :)

Crafterkid12311 months ago

could this make square shapes at least 4.5 inches big??

Dzucky2 years ago
Where might you get a Mindstorms RCX smart brick cuz it doesnt come with the 2.0 set.
Mr.Stein4 years ago
You think I could modify this to use Arduino and servos?
When I first saw the instructable, I thought he would have used and Arduino. I think this is the perfect app for those remarkable little computers.
AJMansfield3 years ago
Just so you know: this is not a 'polar' 3D printer. The words 'polar' and 'cartesian' refer to coordinates in TWO dimensions. The proper name for this printer's coordinate system would be 'cylindrical' as opposed to the other two common 3D coordinate systems, rectangular and spherical. Although I understand that saying that this is a cylindrical 3D printer would be confusing because the word also refers to a particular shape, same goes for 'spherical' and 'rectangular'.
jam BD4 years ago
Lego can be so many things.
If you control Lego you control the WORLD!!!
I love this, I'm going to quote that lol. If you control LEGO you control the WORLD.
Mudbud jam BD4 years ago
One of my pet hates is the pluralization of 'Lego'. It seems to be an entirely American thing. Here in Ireland we say 'I built a house out of Lego', as opposed to 'I built a house out of Legos'. Basically, we use the word like you would the word 'Wood' (Try saying that 10 times quickly!) Sorry for my little rant...
Ahh the Lego/Legos debate haha. I've read an announcement directly from TLG (The Lego Group) that neither LEGO nor LEGOS is correct when referring to individual pieces or sets. LEGO is a combinations of the Danish words for "play well" (leg godt) and is the brand name. When referring to individual pieces or sets, it is correct to say LEGO bricks or LEGO set but not LEGO by itself. This seemed to make sense to me and was a good answer to the debate but then I saw another announcement that said the company didn't care much so I don't know if there's anything official. Calling them Legos is definitely something I've heard a lot and seems to be the most popular way to refer to them in the US. I guess in the end whether you call them LEGO or LEGOS people still know what you're talking about and it's still a great line of building toys.
I think it's because we consider each brick or part to be one "Lego" (even if it's not Lego brand).
Algag Jaycub4 years ago
yeah, because i have x-many lego bricks so i have x-many legos, and sometimes we can pluralize wood, but it is kind of slang, as in I am going in to the woods, as a synonym for forest (but forest sounds much more significant and magnificent)
ninjaaa4 years ago
Nice ;)
jehan601884 years ago
really neat.
hope you develop this further!
dombeef4 years ago
Can the fabric extruder handle the plastic in regular printers?
Mirime4 years ago
Umm replicators are from Stargate SG1 not trek the closet thing i've seen is the borg
Replicators are from Star Trek. They're the devices they use to create pretty much everything, except when it's convenient for a plot for the material to be un-replicatable.
Ok we are talking about two different things i'm talking about a lifeform you are talking about a tool
Ahaha, yeah. I know. I'm a Stargate fan, too. I'm guessing the author meant the replicators from Star Trek, at least I'm hoping. If he intends to build the ones from Stargate, we're in for a lot of trouble! :)
Yep but when i first read that line i thought of the lifeform

take away all the metal objects and she still makes more of her little friends
macrumpton4 years ago
I wonder if you could simplify this device by mounting the work surface on a screw, and as the work surface rotates it automatically lowers the surface a precise amount. It takes some control away of your z axis but simplifies construction a lot. Another simplifying possibility is to use a pivoting arm (like a turntable) rather than a straight track. Of course you would need to compensate for the curved path of the arm as opposed to the simpler straight path of the track, but that is pretty easily done in the software.
EvilElvis5 years ago
Nicely done instructable... always love Legos being repurposed. Just wondering if this concept could be applied to a small dremel cutting tool rather than an extruder.
CactuzHero5 years ago
 Can you please post a video of how it works?
can it make more than mounds? :) i also agree
meztek7 years ago
This is a great idea! I have never seen a polar coordinate machine working, only the cartesian robot. Keep up the great work!
meztek meztek7 years ago
I almost forgot. If you want a material that will become hard, you should try fabepoxy. It was formulated for the Fab@Home project, which has a similar extruder to yours. See http://www.kraftmark.biz/order.html to look into it.
Gene Hacker (author)  meztek7 years ago
What's its viscosity? I use frosting because it's cheap and a good test medium.
...and tasty.
What does viscosity mean? It definitely will work in your fabric pen. I would ask kraftmark what the viscosity is. They created it.
viscosity just means how thick it is. eg: honey has a higher viscosity than water.
Gene Hacker (author)  meztek7 years ago
Resistance to fluid flow. Have you handled this stuff before? Is it about as viscus as frosting? Could you give me a comparison to other products? I am thinking of replacing the air pump I have with a tire air compressor, so I can extrude more viscus media, so this might not be a problem anyway.
I have not handled it before. I hope to get some in the next few weeks. When I do, I will get back to you.
CoolKoon5 years ago
Say, do you have any news on the control software? Or any tips which could help one do some programming should he decide to do something similar?
Silence5 years ago
Slap a cake under that frosting extruder and you can make a pretty funky happy birthday design !!
ARJOON5 years ago
how about the controllers
Frag5 years ago
unfortunately, this not being a cartesian printer you can't steal the programming from any old printer and modify it as needed. the only thing im unsure of in this instructable is if you have a motor set up under the turntable. i haven't gotten a chance to make one of these yet, but as soon as i do ill get to work on a code to manipulate both the turntable and the printing arm. GREAT IDEA BY THE WAY using a Polar 3D printer. im envious of your idea and manipulation of Legos
zack2475 years ago
now i just need $400 for the nxt set and im good to go!
KnexFreek5 years ago
 DUDE!!!! Make the fifth picture the intro picture!!! Than the ratings will go up substantially!!!!!OMG!!!
macrumpton5 years ago
It looks like a great project. I wonder how hard it would be to create a printer that uses hot glue. You could control the flow of  the glue with compressed air and maybe have a small air jet to cool the glue after it has been deposited.
conrad24687 years ago
ok i have an off subject question (kind of) i want to make a model only on a program but it has to have moving parts ex. a gun whereas the when its fired all the parts react like another round will go into the chamber and the firing pin will reset. does anyone have/know of a program with these reactive physics in it?
H3xx conrad24686 years ago
SR 3D Builder. Its an open source 3d Lego set. it has its fair share of bugs but its under active development and has a massive Lego data base.
maybe blender 3d?
lol thats a really hard program to use...ill just stick with incredibots...
ok i dont know if its to late for your model program, but try phun. it is a physics simulator. download: here click download phun, then select the proper file for your os. youtube video of your gun : ) here though possibly something a little more simple, but it might be a little hard to reset itself... anyway, if im too late, still try the program!!
Derin A.C.E.6 years ago
join the phungineers group!
i've made one just a day ago and I'd going to post a ldd, rbt and movie on the mindstorms site. www.legomindstorms.com you just need to make a beam with very much pins in it and then make a sort of hammer. make a program that will push the hammer if pushed the touch sensor. and release it when you release the touch sensor. nilsepils
I was thinking of a program A.C.E. nailed it but good idea
skinnyTod6 years ago
Hi - just came across this - looks cool. You don't mention the code part (or I missed it). How are you handling the coding?
Viaticus6 years ago
Indeed...I'm with Jim Cook...I'd like to see it do something. The concept is awesome, but it seems an extraordinary amount of time and cost to build a machine that pumps out green cake icing in the shape of dog poo (or squatty Christmas trees...dumbbells...etc). We anxiously await additional pictures, etc. The suggestions for materials were useful - a more permanent, non-edible material that is fast drying would really open up the possibilities. I just can't think of anything like that right off, that wouldn't require a heat source to melt the medium before extrusion. Good luck and keep us posted!
ferrari4846 years ago
lol nice
Romi Sharpe7 years ago
Now, don't get discouraged but, for about $40 000 you can buy The Contex ZPrinter 450. It's a 3d printer alrighty. They prefer to call it "Rapid Proto-typing" though. It does have a nice ring to it. As you can see, these two ideas have the potential to transform economies. Could be quite devastatingly chaotic if not handled properly. The entire manufacturing sector could be rendered obsolete virtually overnight. When this technology takes off, certainly Moore's law or some such reality will drive development like a vigorous chemical reaction.
This isn't exactly new technology, but; you can build a 3d printer for about 500 euros its called the reprap he put a link to it in the instructable. That could ruin manufacturing. It can produce 60% of its own parts and uses all open source software, and fits on your desk.
theres microwave size 3d printer thats only cost about 5000$ to 6000$ heres the url http://www.engadget.com/2007/05/08/desktop-factory-to-sell-5k-3d-printer/
Gene Hacker (author)  Romi Sharpe7 years ago
Well, there is one problem with all Z-corp printers, the parts they make are fairly fragile. So don't expect Z-corp printers to cause economic chaos If anything's going to cause economic chaos it's going to be an electron beam melting(EBM) based 3d printer.

Parts made from EBM can be made from titanium and even used in airplanes. They are quite strong and accurate(but you don't get the pretty colors of a Z-corp). It's just about as replicator as you can get.
No less fragile than cake icing;~) but I hear you. Z-corp seems to be focusing on appealing to the mock up market, perhaps because of the fragility issue. Exciting none the less. The EBM sounds like a decent approach to dis-integrating and re-integrating metals. I'm impressed with your co-ordinate system. I'd like to see you apply the polar aspect of it to the printing table. In this way it might be be fairly "easy" to adapt conventional 2d printers. It occurs to me that much of the technology already exists for many useful applications but for some reason hasn't been applied. For example, by expanding the palette of materials able to be deposited we could design and print functional electronics right on to paper or similar substrates. Conductive ink can't be too hard to make. How about some extremely fine ceramic slurry for resistors...? Plastics could also be easily deposited. You see where I'm going with this.
JellyWoo7 years ago
wait, so it prints stuff out of frosting?!?!?!?! how is that better than chocolate???
What about if it made stuff out of jelly, jellywoo
well i was thinking that it could make something that you could keep for a long time and not like melt in the summer or get eaten by your dog.
Gene Hacker (author)  JellyWoo7 years ago
I use frosting because it is cheap, readily available, and easily 'erased.' I am still working on getting the control software right. Plus chocolate requires heating and temperature, which I have not yet implemented yet.
what about using caulk or plaster that might work...
If you put in heating and temperature, you could move right past food and go straight to molten plastic :D
Make a instructable!!
interesting, i might look to do that.
ind you could use it to put a "frosting sculpture" on a cake, and i like frosting
great idea! i never thought of that
oh, okay.
Lew86 years ago
I no it would be lovely to start a 3d printing revolution and all but if you ever look inside the modelling workshops of an architecture company you can actually find huge 3d printers that use wax the create whole model buildings! just thought u might be interested? it costs about 900 pounds to do a single 3d draught usually on a 3d printer, so well done for making such a simple and quite effective (for lego) 3d printer. nice Instructable!
viacin7 years ago
ha ha nice. fat man's printer
szechuan537 years ago
sweet... 5/5 and fav'd
GWJax7 years ago
Nice work!! I've got to try this one out! Jax
ivanirons7 years ago
You sir are a genious! I didn't know my legos had THAT in them. Hats off!

Have a good one,
Rapid Prototyping Info
supernova127 years ago
this is so cool that it would freeze if it was any cooler. it's awesome!
this is cool and all....but do u have a video of it in action? that would make this instructable even cooler and maybe i'll make one! nice job! :)
dude! this instructable is amazing!! are you some kind of demented genius?!?! or are you just an average joe with ALOT of time on your hands?!?! sweet instructable!! +1!
Gene Hacker (author)  Ltcheesecracker7 years ago
This is just something I clobbered together over winter break. I could use a lot more time on my hands. BTW, please make one so I can start ghetto teleporting things!
Gene Hacker (author)  ferrariman6107 years ago
I do, but I am having trouble getting it on the computer.
Gene Hacker (author)  Gene Hacker7 years ago
And by the way please make one!
normaly i would try to make one, but my lego building abilities are very limited, and I would probably need the LDraw diagrams to even know where to begin.......i'll try to make a similar one, but yours will probably be better
stasterisk7 years ago
When did you originally make this? Do I correctly recall hearing about this some time ago?
Gene Hacker (author)  stasterisk7 years ago
I made this within the last few weeks. Someone else did make a 3d printer out of Legos, but their's was cartesian and could only print chocolate. http://www.instructables.com/id/3D-chocolate-printer-made-from-LEGO/?ALLSTEPS I have successfully printed frosting and I am working on printing silicone, easy cheese, and epoxy.
Hmm.. I'm reasonably certain I read about a polar 3D hot glue printer, not on instructables. If I recall correctly, before RepRap was more than an idea. This memory is perhaps associated with reading some early volume of Make.
Gene Hacker (author)  stasterisk7 years ago
Was it this one?
Gene Hacker (author)  stasterisk7 years ago
I've never heard of it could you try and find more info on it? I tried looking up all the information I could about polar printers and it seems that very few people have built them(even for 2d purposes). Do you know if they figured out how to control it to produce complex objects?
Elektor magazine had an article about a PCB drill that used polar coordinates. That was in 2001, you can buy the article and other things for the project on Elektor's webpage:

Or go to the (now apparently out of business) manufacturer, which has the article online:
(Support -> Manuals)

Gene Hacker (author)  tw70037 years ago
That thing is amazing! Especially that multi-headed one. I wish the movie of it in operation worked Do you know where I can get the next article on it? Could my local library have it?
beerden7 years ago
The cool thing about Lego is that it's both singular and plural. Don't go looking for a rusty old "s" hiding in the tall grass and mud beneath the logo in Denmark because you won't find one. But I suppose you could build one out of Lego. With the right materials and resolution, I would use one for replicating Lego bricks, maybe big ones at first, in the spirit of the reprap.org project.
Gene Hacker (author)  beerden7 years ago
Does grammar really not matters much that anymore? Well, I think my printer should be capable of printing out big Lego bricks, but you would have to use support material or geometry. Because Lego bricks are hollow, you have to have something to support the extrude, like frosting. But before I can do that I need to get my control software worked out. Currently, I have worked out the math, now I just need to figure out why my code won't compile. But if anyone has any code they want me to try, send it to me and I'll try it out. If it works, I'll send you a print out.
callmeshane7 years ago
What flavour is the green poop?
Gene Hacker (author)  callmeshane7 years ago
It is a cone of green frosting. I knew I should've printed out a shot glass now.
Awesome... your pieces look pretty dirty... haha. That has nothing to do with the Instructable because it is still great!
Gene Hacker (author)  GorillazMiko7 years ago
Yep, they are. I bought the Lego table at a garage sale for around $10 and it was covered in a layer of dust that has resisted my best vacuum cleaning efforts.
Grubby plastic is no match for dishwasher detergent. The stuff is pretty harsh, so wear glasses and gloves if you're using it by hand. A bristle brush works wonders on Lego and other small parts. My favorite is a fingernail brush from the auto parts store, with slightly stiffer bristles than you find on most nail brushes. Squirt the detergent straight on, then scrub it around with a small amount of water to get it into all the nooks and crannies. Give it a minute to work, then scrub again and rinse. Cascade is my go-to cleaner for crud and stains that resist normal cleaning methods, and it hasn't failed me yet. (Works well on oil-stained driveways, too!)
simharry7 years ago
well you can do it visa versa ( however it is spelled) and hook a mindstorms sensor to a rcx i think.
simharry7 years ago
there is actually a way to connect a rcx rotation sensor to a nxt sensor input. you use the nxt to rcx converter cables , you can find them on lego .com
Gene Hacker (author)  simharry7 years ago
I am looking for a way to hook a rotation sensor up to the Scout. Worst case, I just use a touch sensor to make my own. I don't need rotation sensors for the NXT, as the NXT has rotation sensors accurate to 1 degree built right into its motors.
KaanErturk7 years ago
A cool one! But replicators are from Stargate, not Star Trek ;)
Yes and no. Star Trek has machines called replicators, which make things. Stargate has Replicators, which are a race of robots.
Right, I've got it wrong by replicators. Thanks for this update dude.
indyguy7 years ago
You also need to give credit where credit is due, like where you received the idea: www.reprap.org

I believe this is the addy where you posted for assistance in their forums: http://forums.reprap.org/read.php?1,6226

I am sure the folks over at RepRap.org and those who gave you advice in your post over there will appreciate the recognition.

In regards to the instructable as a whole, great concept to use the legos and the mindstorm set. They are probably less expensive than other components (Though using the legos defeats one of the purpose of the reprap, to produce parts form another machine to make your own.)

Would love to see you manufacture some lego blocks maybe, since those are the main component of the machine.

Gene Hacker (author)  indyguy7 years ago
Well, the reprap people were helpful, but I did not use any of their ideas. Thank you for reminding me! As for the manufacture of Lego blocks, I need to work out the control software. But, it is definitely possible.
tyeo0987 years ago
Or you could use RCX NQC and use one smart brick, using the sensor ports as outputs...
Gene Hacker (author)  tyeo0987 years ago
Dang, you can do that? I am using NXC to program my NXT. Do you know if there is any way to hook up a rotation sensor and a light sensor to an RCX or a Scout? Because that would really help me. The reason why I used NXT to control everything but the Z axis is that NXT has rotation sensors built right into the motors that are accurate to 1 degree. 1 degree of rotation on the motor that controls the R axis translates to 0.1 millimeters.
Jim Cook7 years ago
Well done! I like it. Where can I see examples of what it can do?
Gene Hacker (author)  Jim Cook7 years ago
That's awesome! I see the compatibility w/ a 3d scanner (well, TIm's version, at least). This has extreme potential, nice work!