Building Your Own 3D Printer
1. Frame
Image : empty RepRap Prusa Mendel frame. Notice the various printed parts that keep the frame together. source
The frame gives the printer its stiffness. The three axes of the robot will be added to this frame. The frame consists of threaded rods connected together with printed parts (these are called the vertices.)
RepRap: the printer that can print its own parts
The Rep in RepRap stands for reproduction. RepRap printers are designed in such a way that they can print their own parts. As soon as you’ve got your printer working you can print parts for a The Rep in RepRap stands for reproduction. RepRap printers are designed in such a way that they can print their own parts. As soon as you’ve got your printer working you can print parts for a
Apart from the vertices the frame also contains printed parts to hold and control the Y-axis and Z- axis. On the top left and top right you can see the printed parts that will hold the stepper motors of the Z-axis.
Image : RepRap Prusa Mendel frame with smooth rods for Y‐axis and Z‐axis mounted source
On image 3 you can see the frame with the smooth rods added for the Y-axis (the horizontal rods) On image 3 you can see the frame with the smooth rods added for the Y-axis (the horizontal rods)
2. Yaxis and bushings
Image : RepRap Prusa Mendel frame with Y‐axis installed source
On image 4 you see the print bottom plate assembled on the Y-axis smooth rods. The Y-axis has one degree of freedom: it can move between the front and the back of the frame. The Y-axis is controlled by a belt attached to a stepper motor with pulley that you can also see on the image. The print bottom plate has four bushings attached that have been glued to the print bottom plate.
The RepRap axes - like many CNC machines - move over smooth rods with bushings or more recently with linear bearings.
Bushings are actually plain bearings. They slide over smooth rods and provide almost no friction when moving up and down the rods. Usually plain bearings are used to turn around a cylinder (or to have the cylinder turn inside.) On the RepRap the bushings don’t turn, instead they linearly move up and down the smooth rods following an imaginary line on the rods.
Linear bearings have little balls inside and provide free motion in one direction. Both bushings and linear bearings can be either printed or sourced as metal parts. Metal bushings are made from brass as it's the only metal that has low friction and is self-lubricating. RepRap designs that use linear bearings typically use LM8UU metal bearings. The standard RepRap Prusa Mendel design uses bushings that are more than good enough for the purpose. Some people believe a RepRap printer looks more cool when fitted with LM8UU linear bearings (but this drives up the price.)
Homemade 3D printers are meant to be customized
If you would like linear bearings on your printer then by all means go ahead and print the parts[ 2 ]!
Image : brass bushings inserted in printed parts source
Image : printed linear bearing source
3. Zaxis and Yaxis
Image : RepRap Prusa Mendel frame with X‐axis, Y‐axis and Z‐axis installed source
On image 8 you can see a RepRap Prusa Mendel frame with Y-axis, Z-axis and X-axis assembled. The Z-axis and Y-axis are actually part of one construction. The Z-axis moves the X-axis up and down the frame. The X-axis moves the extruder left and right within the frame.
Image : X‐end idler part on the left‐hand side, X‐end motor part on the right‐hand side source unknown
The Z-and-X axis construction consists of two printed parts called the X-end idler (left image 9 ) and X-end motor (right image 9 ). The X-end idler has two vertical sections: a square open box and a hexagon structure. In the square open box two bushings are glued. This box serves as a guide for the vertical smooth rod. In the hexagon structure two M8 bolts and a spring are mounted. A threaded rod is turned into these bolts. This threaded rod is also connected to the stepper motor on the top of the frame. The stepper motor will turn the threaded rod around its axis that in turn will make the X-end idler move up and down. You can see the assembled X-end idler on image 10 :
Image 0: assembled X‐end idler source
The X-end motor has the same two sections and is assembled in a similar way. As you’ve noticed on the images the Z-axis is controlled by two stepper motors. It turns out it’s both cheaper and improves accuracy to have two stepper motors on the Z-axis instead of one motor and a belt (mainly because the later requires a much more complicated construction and an expensive belt.) The Y-axis and X-axis are controlled by one motor and a belt, here two motors don’t make sense.
4. Extruder
The RepRap Prusa Mendel is typically equiped with a Wade’s geared extruder[ 3 ]. This extruder consists of two parts: a cold top part that feeds the platic filament and a hot bottom part that melts and extrudes the plastic. These two parts are commonly called the Wade extruder (the cold part) and the hot-end (the hot part).
Image : Wade's geared extruder source
The Wade extruder consists of a large gear that is driven by a stepper motor. This large gear drives
a bolt that pulls the plastic filament and pushes it into the hot-end where the plastic melts.
The hot-end is usually a brass bolt with a hole drilled down its vertical axis. This screw is called
a heater barrel. There are two sizes of filament available: 3mm wide and 1.75mm wide. The hole a heater barrel. There are two sizes of filament available: 3mm wide and 1.75mm wide. The hole
Two methods exist for heating the hot-end: using a resistor or using a NiChrome wire. A NiChrome wire is the easiest to get started since you will only need a heater barrel with a nozzle. A resistor requires a heater block that is screwed onto the heater barrel.
Image 12 shows a heater block with a resistor installed. The heater block is screwed into a heater barrel:
Image : heater block with resistor installed source
Image 13 shows a heater barrel wrapped with NiChome wire:
Image : heater barrel wrapped with NiChrome wire the assembly shown in this image is not finished source
A hot-end has three more crucial components: a thermistor to measure the temperature, a heat barrier to separate the hot-end from the cold-end (without this the cold-end would melt) and the nozzle where the melted plastic flows out of the heater barrel.
The thermistor is connected to the electronics board - just like the resistor or NiChrome wire - and allows the electronics to measure and regulate the temperature of the heater barrel. The heater barrel operates at a configurable temperature, without the thermistor that temperature could not be The thermistor is connected to the electronics board - just like the resistor or NiChrome wire - and allows the electronics to measure and regulate the temperature of the heater barrel. The heater barrel operates at a configurable temperature, without the thermistor that temperature could not be
The heat barrier prevents the heat from the heater barrel to rise to the cold part. The cold part consists of printed parts and these would melt if they became too hot. Typically PEEK is used as a heat barrier. PEEK can resist high temperature and transfers very little heat. PEEK however has a number of disadvantages: it’s not easy to find in the format suitable for use on an extruder, it’s pretty expensive as well and it requires a PFTE tube inside to help the flow of filament. PFTE tube can be difficult to find as well.
At least one person has assembled an extruder where PEEK and PFTE was replaced with a piece of
bamboo[ 4 ]. Bamboo has the same properties as PEEK: resists high temperature and transfers very
little heat. It is however much cheaper and much easier to find. The nozzle is the most important part of the hot-end. The nozzle is the end of the heater barrel
where the melted plastic is extruded. The nozzle needs to have a sharp enough tip and a central hole that is less than 1mm (typically 0.5mm.) Image 14 shows a heater barrel with nozzle:
Image : a heater barrel. Suitable for either NiChrome wire or Image : a heater barrel. Suitable for either NiChrome wire or
5. Xcarriage
The assembled extruder - including cold-end, heat barrier and hot-end - is mounted on the X-axis carriage. Image 15 below shows an assembled X-axis with two smooth rods, the X-end idler and X- end motor printed parts and the printed X-carriage:
Image : assembled X‐axis with two smooth rods, the X‐end idler and X‐end motor printed parts and the printed X‐carriage source
The X-carriage can use bushings or linear bearings. The X-carriage is controlled by one stepper The X-carriage can use bushings or linear bearings. The X-carriage is controlled by one stepper
Image : assembled Wade's geared extruder mounted on the X‐ carriage. Notice the belt in the background source
6. Print plate
Printed parts are printed on the print plate. The three axes move together so that the nozzle can move above the print plate in an area of 200mm wide by 200mm deep by 100mm high.
The print plate actually consists of two plates: the print bottom plate that is mounted on the X- axis smooth rods with bushings or linear bearings and the print top plate that is mounted on the The print plate actually consists of two plates: the print bottom plate that is mounted on the X- axis smooth rods with bushings or linear bearings and the print top plate that is mounted on the
screws so that it can be easily adjusted. Image 17 shows both print plates one stacked on top of the other. The springs are clearly visible. The bottom print plate is mounted on the X-axis smooth rods with printed bushings.
Image : top print plate stack on bottom print plate. The springs are clearly visible. The bottom print plate is mounted on the X‐ axis smooth rods with printed bushings source
A popular add-on for your printer is the heated bed. These significantly reduce the amount of warping on printed parts, especially on the lower layers. Warping is caused by the uneven cooling of A popular add-on for your printer is the heated bed. These significantly reduce the amount of warping on printed parts, especially on the lower layers. Warping is caused by the uneven cooling of
hot material won’t[ 5 ]. This uneven shrinking will cause straight edges to bend and might cause
structural failure in parts. Warping is especially a problem for the lower layers of a part since the print plate will cool those layers much faster than higher layers.
The bottom section of the left-hand part on image 18 below clearly shows warping while the identical right-hand part doesn’t:
Image : left‐hand part clearly shows warping in bottom section source
The solution is to print on a heated bed so that the entire lower section of a part is kept at the same temperature. A heatbed can heat the top print plate up to 100C. Image 19 shows a heatbed installed The solution is to print on a heated bed so that the entire lower section of a part is kept at the same temperature. A heatbed can heat the top print plate up to 100C. Image 19 shows a heatbed installed
Image : heatbed mounted on RepRap Prusa Mendel top print plate source
The heatbed remains on for the entire duration of the print. Usually a glass plate is installed on top of the heatbed. If the heat would be turned of after a few layers the printed part would eventually come loose due to the temperature drop and the print would fail. A heatbed can either be bought or
home-made. Buying is of course easier but building it yourself is feasible and cheaper[ 6 ]. When you install a heatbed be sure to check the temperature of the transistor on your electronics board. If it gets very hot you might have to install a little heat sink (you can find those very cheap on ebay or in home-made. Buying is of course easier but building it yourself is feasible and cheaper[ 6 ]. When you install a heatbed be sure to check the temperature of the transistor on your electronics board. If it gets very hot you might have to install a little heat sink (you can find those very cheap on ebay or in
Warning on installing heat sinks
Whenever you install a heat sink on any electronic component always put heat paste between the component and the heat sink. With heat paste the component and heat sink will warm up more or less evenly. Without heat paste the component won’t be able to transfer the majority of its heat to the heat sink (air transfers heat poorly.) You can find heat paste cheaply on ebay. Never use glue instead of heat paste!
7. Electronics
The electronics board controls the printing process. Several electronics options exist for RepRap printers (they are all open-source.) Currently the most popular are:
RAMPS, a DIY shield board for Arduino MEGA Sanguinololu, an all-in-one DIY board with microprocessor on board
The RepRap electronics board has several functions:
Process G-code instructions. Control the four stepper motor controllers (there are five stepper motors on a RepRap Prusa
Mendel but both Z-axis motors are connected to the same stepper motor controller.)
Control the temperature of the hot-end and monitor the hot-end thermistor. Monitor the end-stops (end-stops are used for homing the three axes, see later section.) Control the temperature of the heated bed and monitor the heated bed thermistor (the heated
bed is optional.) The electronics board is connected to the PC using a USB-to-serial converter. The Arduino used with
the RAMPS board has such a converter built-in, so does the Sanguinololu board. The RAMPS electronics board has been around longer than the Sanguinololu and has seen regular
updates. RAMPS is a shield board that needs to be connected to an Arduino MEGA 1280 or 2560 board (or a clone board.) The RAMPS has these additional features:
One extra heater / thermistor channel (three in total) Optional SD card reader
Image 20 shows a RAMPS board mounted on a Arduino MEGA board with four Pololu stepper motor controller boards installed:
Image 0: an assmebled RAMPS board mounted on a Arduino MEGA board with four Pololu stepper motor controller boards installed
source
The Sanguinololu board is a more recent addition. It doesn’t offer the extra thermal channel of the RAMPS and connecting an SD reader is more difficult. However, all electronics are contained on one board and hence doesn’t require an Arduino MEGA board. This makes the Sanguinololu cheaper than the RAMPS. A complete RAMPS DIY kit including Arduino MEGA clone and four Pololu stepper controllers will typically cost about $100 or €100. A complete Sanguinololu DIY kit will typically only cost about $80 or €80.
A few things have to be taken into account though. When building your own Sanguinololu you will have to solder a very small chip[ 7 ] (the USB-to-serial bridge). Also, you should make sure the
ATMega microprocessor comes with the Sanguinololu boot loader installed. If this is not the case you will have to install this boot loader yourself and that is pretty complicated[ 8 ]. Ask your vendor in ATMega microprocessor comes with the Sanguinololu boot loader installed. If this is not the case you will have to install this boot loader yourself and that is pretty complicated[ 8 ]. Ask your vendor in
the PCB’s cannot be etched at home. Actually, the Sanguinololu board can’t be etched at home at all, RAMPS boards versions 1.25 or earlier can be etched at home with some tweaks[ 9 ].
If you want to follow the path of least resistance you should go for a RAMPS board. But maybe you like the Sanguinololu’s small size and lower price. Image 21 shows an assembled Sanguinololu board with four Pololu stepper controller boards installed:
Image : assembled Sanguinololu board with four Pololy stepper controller boards installed source
8. Stepper motors
There are five stepper motors on the RepRap Prusa Mendel:
One to control the Y-axis One to control the X-axis Two to control the Z-axis One to control the extruder
Normally all five motors on a printer are the same but this is not required except for the two motors that control the Z-axis: these must be identical. The RepRap Prusa Mendel has been designed to use bipolar NEMA17 motors. NEMA17 determines some of the dimensions of a stepper motor.
Image : the internals of a stepper motor source
Not every NEMA17 motor is equal
The most important aspect of a stepper motor is its torque. However, the amount of torque the motor will actually supply is also determined by the stepper controller board.
A stepper motor is a special kind of electric motor that is often used in robotics. The motor has two sets of internal coils positioned around a central teethed shaft that contains a permanent magnet. Each set of coils is part of a phase. The coils the belong to the same phase will generate magnetic A stepper motor is a special kind of electric motor that is often used in robotics. The motor has two sets of internal coils positioned around a central teethed shaft that contains a permanent magnet. Each set of coils is part of a phase. The coils the belong to the same phase will generate magnetic
steps[ 10 ].
9. Stepper motor controllers
Controlling a bipolar stepper motor is pretty complicated, especially in micro-stepping mode. Unipolar stepper motors are easier to control but they offer less torque for the same motor size. Special stepper motor controllers have been developed that take over the complexities of controlling
a stepper motor. With such a controller one only needs to send one signal to make one micro-step. This seriously simplifies controlling the stepper motor.
The RepRap community has chosen to use Pololu stepper motor controllers. These come in the form of a small board with one IC - the Pololu stepper motor controller - and a few passive components. Pololu offers both the IC and the board. This board uses very small components so has to be factory assembled. In late 2010 Pololu was experiencing difficulties to ship enough boards so RepRap community member Joem decided to design an open-source version of this board called StepStick. This board still uses the Pololu IC that never was is short supply. One assembled StepStick board usually costs about $10 or €10. Four StepStick boards are required for a RepRap Prusa Mendel printer.
Warning about StepStick board
RepRap community members have reported StepStick boards with short-circuits in them! Obviously this might destroy both your StepStick board and your electronics board. Before installing a StepStick board always verify with your multi-meter there are not short-circuits on the pins.
When stepper motors are in operation and stand still they still use current. For this reason each stepper motor controller has a potentiometer to control how much current is sent to the stepper. If you send too much current you might use more current than is required (and hence increase your electricity bill.)
For this reason is it advised to close the potentiometer on each stepper motor controller by turning counter-clockwise all the way and then open the potentiometer about ¼ th of the way. When you discover one of your steppers does not provide enough torque you can open the potentiometer of that stepper motor controller at little bit further.
10. End stops
At the start of a print job all three axes have to be moved to their starting or homing position. This is the zero position of the Cartesian robot. The axes can’t move any further than zero (they can’t move to a negative position.)
To achieve this three end stops need to be installed, one for each axis. A end stop needs to be installed at the position where the axis shouldn’t move beyond:
For the X-axis this should be the position where the nozzle reaches the left-hand side of the print plate.
For the Y-axis this should be on the back-side of the axis so that the print plate is moved to the back far enough that the nozzle ends up on the forward of the print plate.
For the Z-axis this should be the position where the nozzle barely touches the print plate. When printing the software will make sure the Z-axis is lifted a little before printing the first layer.
You can choose between two kinds of end stops: optical or mechanical switch. The mechanical switches are preferred since they are much cheaper, easier to install and work just as well as optical end stops.
Mechanical vs. optical endstops
Switches have a limited number of on/off cycles. However, most purpose built micro-switches are rated for well over 10,000 cycles and will last years[ 11 ]. Optical endstops are on paper more reliable than mechanical endstops but in practice they are not (todo: discuss.) You should go for mechanical endstops.
Proximity sensors are especially useful for the Z-axis. The starting position of the nozzle over the print plate is crucial. A Hall sensor detects the presence of a magnetic field. A magnet is glued to the bottom of the X-end idler or X-end motor. A small potentiometer allows you to fine-tune the distance between the nozzle and the print plate. This is much more practical than moving your mechanical or optical endstop up and down.
End stops are not required at the opposite ends. The firmware you will install in the microprocessor knows how far each axis is allowed to move calculated from position zero. These distances can be configured.
Image : an assembled optical end stop PCB source
Image 24 shows a mechanical end stop mounted on the Z-axis. Notice the nozzle in the background is hovering a few centimeter above the print plate meaning the X-end idler part is positioned just a little bit to high to be in this picture. From the nozzle and print plate positions one can also deduce the X-axis and Y-axis must be in (or near) position zero. The front of the printer frame is to the right in this image.
Image : mechanical end stop mounted on Z‐axis source
[ 2 ] You can find the X-axis parts with linear bearings for a RepRap Prusa Mendel here . [ 3 ] You can find the designs for the Wade's geared extruder here [ 4 ] Instructions for bamboo as heat barrier here . [ 5 ] See this excellent guide for more details on warping
[ 6 ] See these instructions for building your own heatbed [ 7 ] Instructions on how to solder the small chip on the Sanguinololu board [ 8 ] See these instructions for loading the Sanguinololu boot loader [ 9 ] See here for details on how to etch a RAMPS board yourself
[ 10 ] This applet demonstrates how micro-stepping works inside a stepper motor (note: the stepper motor shown in this applet is unipolar while RepRap uses bipolar motors. The principles however remain the same.)
[ 11 ] Source
Plastics
A RepRap 3D printer is most often used to print either of two thermoplastics: ABS or PLA. The plastic material is arranged in filament.
Image : blue filament on a spindle source
ABS and PLA are very different plastics and they each require specific printer configurations. ABS is made from petroleum and is more flexible than PLA. PLA is biodegradable, is more rigid than ABS and will dissolve in water. ABS is more prone to warping than PLA. Good printing results will require
a heatbed for ABS. For PLA you can probably get printed parts without warping without a heatbed.
There are many different kinds of ABS and PLA. If your printer is perfectly tuned for the plastic of one vendor you might need to redo your configuration after you’ve switched vendors. PLA has a lower melting temperature than ABS. Take into account however that the thermistor on a NiChrome wire hotend typically reports lower than actual temperatures. A thermistor on a heatblock typically reports higher than actual temperatures.
Your hotend temperature, extruder speed and axes speeds all need to be in harmony for good printing results. First try to get good printing results at a lower extruder speed (100mm per second). Afterwards you can try to increase the speed. As a rule of thumb printing quality at higher speeds will be worse than at lower speeds although the degradation is usually acceptable.
Tools and skills
1. Mechanical build
1.1. Wrenches and keys
1.2. Digital caliper
1.3. Spirit level
1.4. Plumb line
1.5. Installation of Z-axis bushings
1.6. Flat on motor shafts
2. Electronics build
2.1. Soldering
2.2. Cable stripper
2.3. DIY Sanguinololu build You don’t need to be an electronics buff or mechanical engineer in order to build your own 3D
printer. If you can screw a nut on a bolt you can build this printer.
You also don’t need to invest large amounts of money in either parts or tools. The RepRap has You also don’t need to invest large amounts of money in either parts or tools. The RepRap has
1. Mechanical build
For the mechanical build you will need these tools and the associated skills.
1.1. Wrenches and keys
Open end wrenches: M8, M4 and M3 Hex keys if you’ve bought those kinds of screws
1.2. Digital caliper
You can't build a RepRap and make it work without a digital caliper. If you have a normal caliper put it to the side and order a digital caliper. The digital caliper gives a readout of two significant digits after the comma. The digital caliper is required while calibrating your frame and later when calibrating your axes. You can find reliable digital calipers on Amazon for $10 or €10.
Image : Toolzone digital caliper source
There are two important tidbits to remember about digital calipers: When storing away your digital caliper always remove the battery. These devices never really
shut down. Whenever you make a measurement always first reset your caliper to zero, even when it shut down. Whenever you make a measurement always first reset your caliper to zero, even when it
Despite these two small annoyances digital calipers outperform regular calipers in such a way that you can't build a RepRap printer without them.
1.3. Spirit level
A spirit level is used during frame building, axes building and general calibration of your printer. A smaller spirit level is better than a bigger:
Image : Draper spirit level source
1.4. Plumb line
You need a plumb line a one point only during the build: when the Z-axis smooth rods are installed. You can also hang a nut on a string but a plumb line will work much better.
Image : Draper plumb line source
1.5. Installation of Zaxis bushings
Depending on which kinds of bushing holders you're using you need different kinds of tools. There are really two categories:
Seperate bushings like PLA bushings or printed bushing holders for brass bushings Bushing holders integrated into the printed parts. This is generally referred to as the Prusa felt
branch. This is actually a counter-intuitive name. The designer of the RepRap Prusa Mendel printer - Josef Prusa - created a branch[ 12 ] with bushing holders integrated in the printed parts. The original purpose was to glue small pieces of felt into these holders (felt was then used as a bushing.) It is also possible to mount brass bushings in these holder. Later on the parts for LM8UU bearings were also added to this branch. The use of felt as a bushing never really caught on and is now outdated. The bushing holders integrated into the parts are still popular for use with brass bushings and LM8UU linear bearings. Image 29 shows the X-end idler part with integrated bushing holders.
Image : X‐end idler with integrated bushing holders, taken from Prusa felt branch .
1.5.1. PLA bushings or separate bushing holders
You will need these tools:
Glue for attaching your PLA bushings or bushing holders the X-carriage on the X-axis, the bottom print plate on the Y-axis and the X-end parts on the Z-axis.
Table clamp when gluing the PLA bushings or bushing holders to the X-end parts on the Z- axis.
1.5.2. Integrated bushing holders
You only really need a hair dryer. You may find that inserting your brass bushings or LM8UU linear bearings into the integrated bushing holders is pretty difficult. If you warm the bushing holders with
a hair dryer before inserting the bushings or bearings you will find it becomes easier. The heat makes the plastic more malleable.
1.6. Flat on motor shafts
You may skip this section if you're lucky enough to have a flat on your motor shafts. Without a flat your axes or extruder are likely to skip steps. You don't want this so you need to add a flat to your motor shaft.
Image 0: a stepper motor shaft with a flat part source
You will need these tools to add a flat to your motor shafts:
Iron file Play-Doh or Silly Putty or alternative
A vise is really handy for this job. You need a way to stop the shaft from turning while filing a flat. It might be possible with pliers (this might also require more than two hands.)
Follow these excellent instructions on how to add a flat to your motor shafts (thank you spacexula.)
2. Electronics build
Tools for the electronics build are required to solder the components on the PCB (if you've bought a DIY kit) and for endstops and motors.
2.1. Soldering
You need these basic soldering tools for building your own electronics board. If you've bought a pre-assembled board you probably still have to solder cables:
Soldering iron with sharp tip. If you have a broad tip you should consider changing it for a finer one.
Solder wire. Third hand
Image : my own soldering kit
Image : a very useful tool for any soldering task source
2.2. Cable stripper
You can't properly strip a wire of its insulation without a cable stripper. People use knifes and scissors but you shouldn't. You want your printer to work properly so you don't want to damage your cables.
Image : my own cable stripper
2.3. DIY Sanguinololu build
A Sanguinololu board has one tiny component - also called SMD component. This component is called the FTDI chip after the company that produces it. This chip is a USB-to-serial bridge. The ATMega chip used on all RepRap electronics boards can only communicate with a computer through
a serial interface. This FTDI chip allows the communication between the computer and the ATMega chip to happen over USB instead.
The FTDI chip is however very small and is very difficult to solder by hand. If you don't have any The FTDI chip is however very small and is very difficult to solder by hand. If you don't have any
[ 12 ] A branch is like a separate track in a software repository. In a branch things can be worked on in parallel without affecting things in other branches.
RepRap software
1. Arduino software for RAMPS
2. Arduino software for Sanguinololu
3. Firmware
3.1. Downloading the Sprinter firmware
3.2. Configuring the Sprinter firmware to your electronics board
3.3. Uploading the Sprinter firmware to your electronics board
4. Skein software
5. Host software
5.1. Prerequisites for Windows
5.2. Prerequisites for other operating systems
5.3. Downloading Pronterface
5.4. Running Pronterface
6. Slic3r: alternative skein application
A RepRap printer is judged by the quality of the objects it has printed and secondarily the speed with which these objects can be printed. The quality of the prints is determined in part by the quality of your mechanical build. Another important contributor to print quality or lack thereof is the software you use with your RepRap and how it has been configured. The fundamental pieces of software required to run a RepRap printer are discussed here.
You will need at least four applications installed on your computer to run a RepRap Prusa Mendel 3D printer. They are:
Arduino software: this application allows you to install the printer firmware onto the ATMega microprocessor. This installation is required each time you want to update the firmware.
Firmware: there are several firmwares available for RepRap printers. The firmware is installed on the ATMega microprocessor and handles the G-code instructions received from the PC. Part of the configuration of the printer has to be done in the firmware.
Skein software: the most popular application to slice STL files into G-code is called Skeinforge. You need this piece of software each time you want to print a part.
Host software: there are also several host application available for RepRap printers. This application is responsible for communicating with the electronics of the printer before and during print jobs. It prepares the printer before starting a print job and then also starts the actual print jobs.
These applications are discussed in turn below.
1. Arduino software for RAMPS
For the RAMPS electronics you need to follow the instructions for installing the Arduino environment:
Windows installation instructions Mac OS X installation instructions Linux installation instructions
COM port to communicate with your Arduino board
Make sure to remember or write down the COM port to which your Arduino is connected. Once the Arduino board is connected to the Arduino software you can skip ahead to the firmware
section.
2. Arduino software for Sanguinololu
For the Sanguinololu board you will need to follow these Sanguino installation instructions:
Windows installation instructions Mac OS X installation instructions Linux installation instructions
COM port to communicate with your Sanguinololu board
Make sure to remember or write down the COM port to which your Samguinololu is connected. Once the Sanguinololu board is connected to the Arduino software you can follow the instructions in
the firmware section.
3. Firmware
There are a few popular firmwares available for RepRap 3D printers[ 13 ]. They are: Sprinter : modern firmware with support for SD cards and easy configuration Teacup : claimed to be faster than Sprinter, more elaborate configuration options
Teacup is a decent alternative for Sprinter. However, because of its easier configuration we advise Teacup is a decent alternative for Sprinter. However, because of its easier configuration we advise
3.1. Downloading the Sprinter firmware
There are two methods to download the Sprinter firmware:
Through the website. By cloning the repository using Git.
If you're not familiar with Git you should download the latest version of the Sprinter firmware from the website.
3.1.1. Download Sprinter through the website
Download the latest Zip archive here . Unpack the Zip archive.
3.1.2. Clone the Sprinter repository with Git
Execute this command:
git clone https://github.com/kliment/Sprinter.git
3.2. Configuring the Sprinter firmware to your electronics board
Each firmware needs to be configured in at least two important ways before you can use your printer properly:
The type of electronics board you're using (RAMPS, Sanguinolo, ...) The steps per mm: these are the steps your stepper motor needs to make for one axis to
travel one mm. This value has to be configured for the three axes plus the extruder. For now you only need to configure the type of electronics board you're using.
The Sprinter firmware needs to know which electronics board and which version of the board you're using. To configure the Sprinter firmware open the Sprinter.pde file in Arduino IDE. This file is located in the Sprinter archive you've downloaded. Edit the Configuration.h file. For now change only one setting that is at the top of the file: MOTHERBOARD . Change the line that says #define MOTHERBOARD to one of these values depending on your electronics of choice:
RAMPS version 1.2 or older: #define MOTHERBOARD RAMPS version 1.3 and better: #define MOTHERBOARD Sanguinololu up to version 1.1: #define MOTHERBOARD Sanguinololu version 1.2 and better: #define MOTHERBOARD
Make sure to save the Configuration.h file (CTRL+S.) Also make sure you’ve selected the correct Arduino board in Tools / Board menu:
For RAMPS this should Arduino Mega (ATMega1280) or Arduino Mega 2560. The value For RAMPS this should Arduino Mega (ATMega1280) or Arduino Mega 2560. The value
followed the Arduino software for Sanguinololu instructions above .)
3.3. Uploading the Sprinter firmware to your electronics board
Uploading your configuration changes
Each time you make a change to the Sprinter firmware you need to upload those changes to you electronics board. Without this steps your changes will not take effect.
Make sure you've opened Sprinter.pde file in the Arduino IDE. Press CTRL+R to compile the Sprinter firmware with your specific configuration to your electronics board. If everthing goes well you should see a message similar to this:
Binary sketch size:
0 bytes of a
byte maximum
When the compilation has completed you can upload the firmware to your board. Make sure the USB cable is connected and LED is on. Hold the reset button on your board and press CTRL-U. When text appears in the black window of the Arduino IDE release the reset button (an Arduino chip can only be programmed for 10 seconds after a reset.) After the upload has completed reset your electronics board by pushing the reset button.
4. Skein software
Skeinforge is the most popular skein application in the RepRap community but it’s also notoriously complicated. Recently software developers in the RepRap community have release Pronterface. This application hides much of the complexity of Skeinforge and is also host software for a RepRap printer. When you install Pronterface there is no need to install Skeinforge separately.
5. Host software
Pronterface is the easiest to use host software for a RepRap 3D printer. It combines Skeinforge into
a much easier to use package. With Pronterface you can load a STL file, have it converted to G-code and control your RepRap Prusa Mendel 3D printer.
5.1. Prerequisites for Windows
Before you can run Pronterface you need to install these applications. There’s is no need to restart your computer after the installations are completed. Install these applications one after the other.
Python 2.7 . Python is the language that Pronterface is written in. pyserial , a library that allows Python to talk to serial ports. wxPython , a library to build graphical user applications in Python.
5.2. Prerequisites for other operating systems
For other operating systems check the prerequisites description here .
5.3. Downloading Pronterface
Pronterface can also be downloaded in two ways. Again, download the latest Zip archive from the website if you're not familiar with Git.
5.3.1. Download Pronterface through the website
Download the latest Zip archive here . Unpack the Zip archive.
5.3.2. Clone the Pronterface repository with Git
Execute this command:
git clone https://github.com/kliment/Printrun.git
Afterward change directory to the Printrun directory and run this command:
git clone https://github.com/ahmetcemturan/SFACT.git skeinforge
This command will clone SFact that is required by pronterface (you can also use another skeinforge version.)
5.4. Running Pronterface
In the unzipped directory double-click on the red pronterface icon. You will see a screen like this:
Image : Pronterface running on Windows.
Select the correct COM port. Also make sure your electronics board is connected to the USB port and has power. Then click the “Connect” button. Pronterface should now have been able to connect to your electronics board. You can now try move your three axes. Start with small movements - e.g. X+1 - and make sure you don’t run into anything.
6. Slic3r: alternative skein application
Slic3r is a new skein application as a replacement for skeinforge. It looks very promising and the user interface is much easier to use. You can convert STL files to G-code and import these G-code files into pronterface.
You can download Slic3r here . Below is a screenshot of Slic3r:
Image : Slic r running on Windows.
Press the "Slice..." button to open an STL file. This will be immediately converted to a G-code file Press the "Slice..." button to open an STL file. This will be immediately converted to a G-code file
Work in progress
Slic3r is a work in progress. It's not as complete or stable as Skeinforge yet. It is much easier to use though.
[ 13 ] See also the list of all available firmwares for RepRap printers.
Buyer's guide
1. Printed parts
2. Vitamins
2.1. Electronics
2.2. Power supply
2.3. Stepper motors
2.4. Hardware kits
2.5. Extruder
2.6. Hotends
2.7. Kapton tape Once you’ve decided to commit yourself you’ll have to shop for parts. A RepRap printer consists of
two kinds of parts:
Printed parts for a RepRap Prusa Mendel Vitamins or non-printed parts like nuts and bolts and electronics.
Check out the RepRap Prusa Mendel bill of materials (BOM) to get a feel of all the parts that are required.
Warning about placing your orders
Don't order anything before checking your planned purchases on the #reprap IRC channel. Only place your orders after the RepRap community members on the IRC channel have approved.
1. Printed parts
In Europe printed parts can be sourced from nophead or arthx. Nophead sells his parts on ebay . Arthx can be contacted on the #reprap IRC channel (his handle is arthx.) Nophead is based in the UK, Arthx in Poland.
For the US also check out LulzBot.com (based in Loveland, Colorado, USA). For both US and Europe also check eMAKERshop.com , a website where RepRap community members buy and sell RepRap parts.
You might also want to check out the casted parts offerd by 2printbeta.de . These are reportedly the only decent casted parts available.
2. Vitamins
2.1. Electronics
2.1.1. RAMPS
These vendors sell RAMPS DIY and pre-assembled kits:
RepRapSource.com (based in Germany) xyzprinters.com (based in the Netherlands) LulzBot.com (based in Loveland, Colorado, USA) UltiMachine.com (based in South Pittsburg, USA)
You can buy an Arduino MEGA 1280 or Arduino MEGA 2560 board from these vendors or on ebay. Also check ruben-ikmaak ( info [at] ikmaak [dot] nl , based in the Netherlands) for Arduino MEGA boards.
2.1.2. Sanguinololu
These vendors sell Sanguinololu DIY or pre-assembled kits. For a small extra fee they will solder the SMD part for you, something which you should certainly not consider doing yourself . Ask the vendor directly in case no such quotation is made on their website.
Voltage regulator
Make sure you get the voltage regulator on you Sanguinololu. A ATX power supply usually doesn't give a clean 5V, better to get 5V for you electronics from the 12V source with a voltage regulator. If you're not sure ask your vendors.
xyzprinters.com (based in the Netherlands) ruben-ikmaak ( info [at] ikmaak [dot] nl , based in the Netherlands) LulzBot.com (based in Loveland, Colorado, USA)
2.1.3. StepStick
Most of the vendors above carry the StepStick or Pololu boards. Be careful to actually buy the A4988 stepper drivers. The A4983 is an older chip and doesn't have overcurrent protection, the A4988 does. You will still find A4983 boards available, better avoid them.
2.2. Power supply
You will need a ATX power supply of about 20A on the 12V channel. The current doesn't have to be higher than 20A but it shouldn't be 15A either. 20A on 12V is enough to run a RepRap Prusa Mendel 3D printer with a heated bed.
2.3. Stepper motors
The RepRap Prusa Mendel 3d printer uses bipolar stepper motors with four wires. The step angle
should be 1.8°[ 14 ].
The SY42STH47-1684A is the ideal stepper motor for a RepRap Prusa Mendel 3D printer because the Pololu stepper drivers can bring out its maximum torque. You want as much torque as possible on your 3D printer. These stepper motors are available from Zapp Automation (based in the UK.) Also check ruben-ikmaak ( info [at] ikmaak [dot] nl , based in the Netherlands.) Ruben also carries these stepper motors.
2.4. Hardware kits
These kits contain all rods, bolts, nuts, washers and springs required to build your printer. Usually they do not include the hardware for the extruder. Neither do they usually included the 608 bearings. Check out these vendors for hardware kits:
2printbeta.de (based in Germany): nuts & bolts kit and rods kit 2printbeta.de (based in Germany): nuts & bolts kit and rods kit
& bolts, belts and printer parts; on many occassions these turn out more expensive than the sum of the parts.
Ask the vendors In case you are not certain whether or not their hardware kits include all the items on the RepRap Prusa Mendel BOM .
Warning on LM8UU metal linear bearings
LM8UU metal linear bearings require your smooth rods to be made from rolled steel. Anything softer than rolled steel will get damaged by the linear bearings and might also damage the linear bearings. Very few kits however provide rolled steel smooth bars. For this reason LM8UU metal linear bearings can drive the price of your printer up significantly.
2.5. Extruder
The printed parts for the Wade’s geared extruder are usually part of the printed parts kit but be sure to double-check. You will probably has to buy a separate Wade's geared extruder hardware kit. These vendors sell them:
2printbeta.de (based in Germany) 2printbeta.de (based in Germany)
2.6. Hotends
TODO
2.7. Kapton tape
Kapton tape is a space-age product. It's tape that can resist the high temperatures typically found around a RepRap 3D Printer. Kapton tape must be put on a heated bed (the filament won't stick to the heated bed itself) and optionally also on the hotend. You will need two widths of kapton tape: 1cm and 5cm. A roll of kapton tape typically holds about 33m. Check the vendors mentioned above for kapton tape, also check ruben-ikmaak ( info [at] ikmaak [dot] nl , based in the Netherlands.)
[ 14 ] See the RepRap wiki page on stepper motors for more details.
Build instructions
1. X Y and Z axes calibration video
2. Printing spare parts
3. Selecting voltage for endstops on the Sanguinololu board
Work in progress
This section will be expanded and improved over time. For now it's made up of bits and pieces of useful information.
Once most or all of your parts have arrived you're ready to start building your RepRap Prusa Mendel 3D printer. This printer come with very good build instructions:
The RepRap Prusa Mendel assembly instructions with video segments . The RepRap Prusa Mendel visual instructions .
For the Wade’s geared extruder:
The overview page . Visual instructions .
In case of doubt
In case you are in any kind of difficult or are uncertain take picture or record video and ask your questions on the #reprap IRC channel.
1. X Y and Z axes calibration video
You have to watch this excellent video by spacexula on how to calibrate the X Y and Z axis:
2. Printing spare parts
After your printer is working properly the first things you should print are spare parts for your printer. Certain parts are known to break . You should preferably have spares of these items:
Set of two Y-axis and X-axis pulleys
Entire extruder set (only in case your printer parts are made from PLA) X-carriage (only in case your printer part is made from PLA)
PLA has a lower melting temperature than ABS. The extruder set and X-carriage made from PLA have been known to get damaged due to the heat of the hotend. If these parts of your printer are made
from PLA you should add a fan to blow air to the top of the hotend and the heat barrier[ 15 ]. This will make damage to your PLA X-carriage and extruder parts less likely.
RepRap Prusa Mendel bar clamp source
RepRap Prusa Mendel Y‐axis and X‐axis pulley source
3. Selecting voltage for endstops on the Sanguinololu board
On the Sanguinololu board you have to select the voltage for the endstops . If you don't make this selection you will not have current on your endstop connectors. This is not a problem when you use three mechanical endstops. However, if you use optical endstops or a hall sensor you will have to select a voltage. Both the optical endstops and the hall sensor require 5V.
[ 15 ] Here is one design for a suitable fan mount.
About this book
1. How to contribute
1.1. Overview
1.2. Create your free GitHub account
1.3. Fork the repository
1.4. Clone your copy of the repository
1.5. Making changes
1.6. Commit your changes
1.7. Push your changes
1.8. Create a pull request
2. Similar efforts
3. Contributors This book is licensed under the Creative Commons Attribution-ShareAlike 3.0 Unported License .
Sharing of this work is encouraged.
1. How to contribute
In case you want to fix typos - there's bound to be plenty, edit this book or if you just want to add content to this book you can do so on GitHub . You need to have a GitHub account. Creating one is easy. You will also need to install Git on your computer. There are Git installation packages available for many platforms. Once you have taken care of all that you should log in to GitHub and fork the repository of this book. Afterwards you can commit and push your changes to GitHub. When that is done you can send me a pull request. The next sections will discuss these steps in more details. There's also a page on GitHub dedicated to pull requests (the page however might be too elaborate.)
1.1. Overview
The idea is simple enough: you want to make a small or bigger change to the content of this book. Problem: you don't have write access to the repository that holds this book's source code. You could send me an e-mail saying you would like to add this and that to such and such section. That's tedious.
Actually you do have write access to this book's source code, in a way. This book's source code is hosted on GitHub, a site for collaborative sofware development. On GitHub - once you have an account - it is very easy to fork a repository. Once you've done that you can make any changes you like.