Make your own 3D Printer

Money no object, we’d all be rolling in 3D printers, albeit while facing some mild discomfort due to the sharp edges and stray 3D prints but rolling in them nevertheless. Since money is the constraint, let’s follow the motto of ‘if you can’t buy it, make it’ and make ourselves some 3D printers!


With 3D printers at the brink of becoming a household item, here’s a quick Gide for the early adopters who want to make a 3D printer before it becomes ‘mainstream’.

Money no object, we’d all be rolling in 3D printers, albeit while facing some mild discomfort due to the sharp edges and stray 3D prints but rolling in them nevertheless. Since money is the constraint, let’s follow the motto of ‘if you can’t buy it, make it’ and make ourselves some 3D printers!

While you can find the used 3D printers online on the cheap and a few models like the One Up 3D printer available for pre-order for about $200, for those who do want to make one themselves, we’re going to be walking you through the process of making your own 3D printer.

To begin with, you have to understand that there are quite a few different types of 3D printers. You have some (more mains stream) printers that have a heated nozzle and a filament is melted and layered vertically. Others use a powder and a laser melts the particles to create an object and some even harden resins to create the object.

In the interest of simplicity, let’s look at the first type we mentioned, which also happens to be rather popular too. FDM or Fused Deposition Modelling is the same technique used by big names like Maker Bot and the wallet friendly open source, DIY names like RepRap as well.

So you want to build your own RepRap 3D Printer.

We’re going with RepRap because they’re a pioneer when it comes to the world of 3D printing for the masses and have a community base so large that most superlatives would end up not doing enough justice. So if anything goes wrong, one can safely expect a quick, response from somebody who has been there, done that.

The RepRap Prusa Mendel

The icing on the cake is really the fact that the RepRap can print its own parts and in a way, it can actually pay for itself and replacements parts are going to be a breeze for the ones with enough foresight. If your friends own a 3D printer, you can find all the printable parts at reprap.org/wiki/ Prusa_Mendel_(iteration_2)#Printed_Parts and make all the parts yourself.

The RepRap Prusa Mendel 2 is what we are building as it is the easiest to put together and gives you the advantage of having a full sized 200mm x 200mm x 100mm work space. While the RepRap Prusa Mendel may be the easiest to build, it is still complicated and would require over 40 hours of work to actually build it. This article is intended to so present a detailed overview of all the components the Prusa Mendel contains and how they work. It would also help one familiarise themselves with how
3D printers work.

What should your shopping list contain?

While the entire list is easily available at reprap.org/wiki/Prusa _Mendel, the Prusa Mendel is made up of:
1) The Frame
2) The X, the Y and the Z axis with their rails and brushings
3) The Extruder
4) The X Carriage
5) The Print Plate
6) The Electronic Components
7) Stepper Motors and their controllers and
8) End Stops
9) Filaments
10) Programmes

The Frame:

The frame is comprised of two triangle shaped structures erected facing each other and joined with the same threaded rods that make the triangles. These parts are held together using printable parts. On this structure we will be mounting the X, Y and Z axes using even more printable parts.

The Frame

Smooth rods that serve as rails for the Z axis will be installed vertically on the outside of the frame while the Y axis’ rails will perpendicular on the inside.

The Axes

In the Prusa Mendel when viewed head on, the X axis moves left to right, the Y moves back and forth and the Z axis moves up and down. While the X and Z axis movements are executed using the same structure, the Y axis, which also doubles up as the base moves independently. All three axes are mounted on rails and run over them so the axes need to be mounted on brushes.

The brushes can either be printed or the sturdier alternative would be to use brass brushings.
Interesting fact: Brass has the least friction and is self-lubricating. Whodda thunk it?

The X, Y and Z axes are controlled by stepper motors, with the Z axis requiring two of them. While it is up to the builder to choose the specifications of the motors for each axis, we and the rest of the RepRap community would advice that you stick to two motors of the same specs when it comes to the Z axis.

In the case of the Prusa Mendel, the X, Y and Z axes can travel across the work space and print an object up to 200mm x 200mm x 100mm in length, breadth and height.

The Extruder

‘To extrude’ means to thrust or force out, so this part’s function is sort of self-explanatory. The extruder is the money maker when it comes to a 3D printer. It is made up of a brass bolt with a hole drilled through it. The hole is around 3mm at the end through which the filament is fed through and the melted filament comes out the other end through a hole that is less than a millimetre across.

The Business End a.k.a The Extruder

The Prusa Mendel’s extruder is called the Wade’s extruder or a Wade’s geared extruder. It comprises of a hot part and a cold part. The cold part is separated from the heat by a heat shield so that the filament doesn’t melt when it doesn’t need to. While it’s possible to build an extruder from scratch, it’s a lot easier to pick one up online. Ebay has extruders for the Prusa Mendel in a price bracket of $25 to about $70 if it comes with a motor for controlling the extrusion. $13 if you want to piece one together though.

An interesting thing that comes to mind here is the 3Doodler, a 3D print pen which extrudes plastic and allows the user to ‘doodle’ in 3 dimensions. It’s available for pre-order on their website and from their videos, seems like a lot of fun.

The X Carriage

The extruder and its motor are mounted on a part called the X Carriage (yes, it’s printable too). The X Carriage runs travels across the X axis on smooth rails and is powered by a belt driven stepper motor.

The X carriage mounted on the X axis

The entire X axis comprises of two X end idlers which are no identical (printed parts again). These parts contain slots for the entire assembly to move across the Z axis using belt driven stepper motors mounted on the top two vertices and the stepper motor that controls the X axis is mounted on the left X end idler.

The Print Plate

The print plate is a two part structure and is basically two flat surfaces stacked one on top of another. While the bottom surface is mounted on the rails and runs back and forth, the actual printing surface is mounted on top. The Y axis is controlled by a stepper motor and a belt drive as well. Needless to say, both surfaces must be completely level.

The upper surface is where the printing actually happens and is mounted using screws which are placed inside springs. The springs help level the printing surface.

Heated Print Plate
Because the print surface cools over the course of the print, the chances of the model warping, cracking and shattering very much exist. This is because the inner and outer sides cool at different level. As the outer side can cool faster than the inner side which has the advantage of being able to stay insulated and keep the heat in, the model warps and is rendered useless.

This can be avoided by using a heated print plate. These print plates can go as high as 100 degrees Celsius and needless to say, be warned and don’t touch. These plates are easier bought than made but making them is so much cheaper. You can find everything you need to build your heated bed at reprap.org/wiki/Heated Bed

The Electronic Components

Now it’s time to discuss the meat of the printer or as the rest of the RepRap community likes to call them, the electronics. Obviously the entire 3D printer would need some sort of firmware to recognise where it needs to print and the objects dimensions. There is a whole list of components available to pick from at reprap.org/wiki/Comparison_of_Electronics.

The top three though are the RAMPS (mounted on an Ardino Mega), the Sanguinololu and the Gen7 the RAMPS have been around for a long time and a lot of people have contributed to its development. The Sanguinololu is cheaper and simpler and the Gen7 is a feature rich DIY project on its own. Both the Gen7 and the RAMPS have a whole bunch of add-ons available too. 

The stepper motors can be controlled with either Pololu stepper controllers or Step Sticks which are mounted on to the boards There are of course cheaper ones available on Ebay and you can find a list of all the places that sell pre-assembled ones at ‘reprap.org/wiki/RAMPS#How_to_get_it’ Both boards are plugged in to your computer via a USB cable but if your board comes with a micro SD card then you can print the .still files directly off the card. If in the event you choose to go for the Sanguinololu, make sure it comes preloaded with an AT Mega microprocessor comes with the Sanguinololu boot loader installed. It’s possible to load it yourself using a boot loader but it’s pretty complicated. The smarter thing to do would be to ask the seller.

The Stepper Motors

The stepper motors are what move the printer across the axes. There are a total of five motors controlled by four controllers. The X & Y axes and the Extruder all use one motor each and the Z axis is controlled by two. While the rest of the motors may be of different specs, the Z axis motors have to be identical or your Z axis might not move properly.

I like to move it move it.

What the stepper motor does is it runs the motors through tiny steps or micro-steps making it easier to control. The stepper motors are connected to the Pololu stepper control. If you are assembling your own board, you can pick them up for about $5 a pop.

The End Stops

The end stops are the places in the print area where the X, Y and Z coordinates are (0, 0, and 0). On the X axis it is at the left most extreme, Y is as far back as the print plate can go and Z is almost touching the print plate. In fact the Z axis jumps up a little bit before beginning to print.

One end stop per axis is enough and the firmware installed in the microprocessor will automatically know how far each axis is allowed to move from zero.
The end stops could either be mechanical or optical end stops but the Ripraps community seems to have a leaning towards mechanical ones.


After the extruder, arguably the most important part in any 3D printer is the filament. ABS (Acrylonitrile Butadiene Styrene) plastic and PLA (Polylactic Acid) are the two most common types of plastics available and each has its own advantages. While ABS plastic is the more durable of the two, PLA is a low more flexible (ABS is actually quite rigid) and is biodegradable.
The only flipside to PLA is that it responds poorly to heat and meets the same fate as the Wicked Witch of the West when mixed with water, when the thermometer goes north of 50 degrees Celsius.

Available in more colours and opacities than you can imagine

The flipside to ABS is that because it is so rigid, it’s more prone to warping so a wise choice we would guess would be to invest in a heated base. The key to good quality printing is really in the balance between the rate at which the plastics are extruded, the temperature of the hot-end and the speeds at which the extruder moves across the axes so try to play around with the variables. Start from a slow speed and work your way up. The Filabot is a system that allows the user to make the filament at home and according to them, save up to 90% on filament costs. It’s pretty flexible too and produces filaments of ABS and PLA of varying thicknesses. You can either put in together or buy it prebuilt and with the soon to be released Filabot Reclaimer, you can convert old projects in to filaments too!

Patent pending

Phew! Now that that’s out of the way, let’s talk about dispensing the filament, A lot of people have come up with a lot of clever, inventive ways to dispense the filament but an easy way developed by the author (patent pending by the way) would be to make one with a few threaded rods. Imagine two triangles joined by more rods (very similar to the frame of our printer). The spool of filament would be threaded through the connecting rods and get dispensed by the extruder.


To actually build your model, you will need three programmes at the most. One will be a CAD programme to actually make your model, one will convert the model in to G-code and the third will communicate with the printer and produce the model. CAD programmes are numerous. While you can pick the one that suits your needs best from reprap.org/wiki/Useful_Software_ Packages#2D_and_3D_CAD_software, a few open source ones worth talking about would be Blender, Free CAD and Shape smith.

Blender is a really powerful open source 3D animation suite which also allows the user to sculpt objects. It is entirely community driven which has led to a lot of bug fixes and there are also a whole bunch of training DVDs you can purchase and help support Blender. Free CAD, like Blender works across multiple operating systems and is more suited for 3D modelling. Its official website freecadweb.org has all the resources you would need to get started.

Finally, Shape smith is a browser based programme and because your set parameters to compose your 3D object, it takes less time to make the objects. The only down side is the fact that you can’t exactly sculpt your objects here. Other free but closed source applications you can look at are Sketch Up which is supremely easy and super intuitive to use and Rhino which is favoured by the jewellery designing community. The only caveat with Rhino is the fact that you can save a total of 25 times before the save feature is disabled and you will need to purchase a license.

The most important thing to remember is that the 3D object is printed layer by layer. This means that the .still file needs to be converted in to a lot of individual layers as a G-code file. Here is where Slic3r and Skein forge come in to play. While Slic3r is newer and isn’t as reliable as Skein forge, it’s much easier to use and spits out G-codes faster than you can say Fused Deposition Modelling (only kidding). Also, unlike Slic3r, Skein forge needs Python to be installed on your computer to run it.

With your G-code file ready, the only step left is to send it to the printer and here’s where ReplicatorG comes in to use. This is the same software that is used by MakerBots, RepRaps and CNC machines alike. With tens of thousands of successful prints, this would be your best bet. Other noteworthy mentions would be Red Snapper and Print run or Pronterface.

Bonus: Other 3D printer types and their plastics

While printers like out RepRap Prusa Mendel and quite a few others use filaments and follow a process called Fused Deposition Modelling (FDM), but there are a few DIY printers out there. Stereolithography is where you use a laser to heat and solidify a resin to build a model Formlabs’ Form 1 being a good example and instead of a bottom up approach to printing used by the RepRap, The SLA (Sere lithographic Apparatus) takes a top down approach. The resin is a photo plastic that cures with the help of UV light and the SLA requires a tank full of that stuff.

A small portion on the surface of the bath is cured. A perforated platform slowly lowers itself across the depth of the tank to expose more resin, layer by layer to the laser.

The point in favour of SLAs is the fact that your model will be ready much faster when compared to an FDM printer but it’s going to set you back a lot more. The resin alone would set you back about a $100 for a litre and built machines would cost as much as a Mercedes.

There are a few DIY projects but it tends to get a little complicated and isn’t as straightforward as the RepRap.

Spoil your kids with a new lunch box every day

Other 3D printing technology range from the use of electron beams to carbon dioxide lasers and ytterbium fiber lasers (are you s#!++ing me?) and unless you are deep in to medical transplants and aerospace engineering, you should stick to the FDMs and the SLAs.

Additional Bonus: What to expect in the near future Biodegradable Lunchboxes

One really awesome thing we can expect is the gradual weaning away from petroleum based plastics. The good news is that our eco-friendly plastic- PLA is now food grade! Scientists at Taiwan’s Industrial Technology Research Institute have developed a type of PLA that doesn’t become a pile of mush when heated and can be used to serve food. What they have done to achieve this is that they have developed a non-toxic nucleating agent that accelerates the crystallization rate of PLA. Why this is important is because PLA is derived from grains and sugarcane and is supremely green. The icing on this 3D printed cake is the fact that it is possible to derive this type of PLA from lactic acid too!

Where can I find more?

The entire RepRap community and all future developments in their models are available at reprap.org. You can find detailed videos explaining how to construct and troubleshoot your RepRap Prusa Mendel.

Are there any alternates I can consider?

You could take look at the Eventorbot by RepRap or the Prusa Mendel i3. Both have a better finish with all the wires and motors hidden away but are slightly more complicated to construct. Printout makes a bunch of kits that only require assembly and are not that bad on the wallet but one also needs to factor in shipping costs and like I mentioned before the One Up and Two Up 3D printers are also really good alternatives but they comes fully assembled so the fun of building your own 3D printer is lost.

I don’t think I will be able to do this!

If these are the words running through your mind then slap yourself and let these awesome people who have done it before inspire you. The first on our list is Afaté Gnikou, a native of the Togolese Republic, Afaté, after being fascinated by the capabilities of a Prusa Mendel, decided to build his own 3D printer using all the e-waste from Europe that gets dumped in open landfills there. After coming through these scrap yards, salvaging parts from old scanners and mainframes, Afaté finally managed to build his first working prototype after six months of toil. The first object this literature graduate (that’s right, he has no background in engineering or science) made was a pen stand with the words ‘droit a rever’ or right to dream inscribed on it.

The Eventorbot

The second person on our list is 15 year old prodigy Angad Daryani, who assembled his first RepRap at the age of 13. He has subsequently developed his own DIY 2D printer, SharkBot and sells them.

The final entrant on our list of inspirational people is Instructables user Mastermind. Being an engineering student with who didn’t have a few hundred dollars lying around, he used his old legos (there were lying around) and using a hot glue gun and the kind of motors camcorders use to move the lens back and forth and built his hot glue 3D printer. Since this is just a prototype, the possibilities for this design are limitless and there’s some serious stuff we can expect.

The LEGObot by Mastermind

Well, we hope we have included all the important things required to build your own 3D printer. You can find all the resources you might need at reprap.org. Good bye and good luck!