Plastruder Mk6 Usage

Download the latest version of ReplicatorG


ReplicatorG is the program that prepares digital files for printing and controls your Thing-O-Matic. It is also used to test your Thing-O-Matic, and upload new firmware to its electronics.

Install ReplicatorG

Download the version of ReplicatorG appropriate for your platform. ReplicatorG runs on Windows, Linux, and Mac OS X.

The most recent version of ReplicatorG is linked to below. Our downloads are hosted on Google Code, where we store older versions as well. You can download the latest version directly from the links below:

Or you can search for an older version of the program to use via Google Code.

Follow the installation instructions for your platform:

Install on Windows


Note: Java now comes bundled with ReplicatorG on Windows, and should not need to be installed separately.

Install Python

The program that slices your model (turns it from a 3D model into a printable path) is called Skeinforge. It is written in python, which you'll need to install. You'll want Python 2.6. Download it from, and follow the installation instructions.

Copy folder

Unzip the folder you downloaded and put it in a convenient directory.

  • Note: If you encounter errors while unzipping the file to your user directory, it may be that the maximum filename length is exceeded. Try unzipping it to another directory, such as C:\Program Files.
  • Windows 7 note: in some Windows 7 systems, some users have had permissions problems when installing ReplicatorG in the "Program Files" directory. If you encounter hanging issues when trying to edit or run Skeinforge profiles, try reinstalling ReplicatorG in a directory other than "Program Files".

Install Drivers

The drivers folder contains drivers for the FTDI USB -> Serial converter chips that the Motherboard uses. If you've already installed Arduino, you can skip this step. Otherwise, follow the instructions on the Arduino website.
Alternatively (helpful for XP systems) download these drivers from the FTDI website.

Here are some instructions specifically for installing the new drivers you'll need to use with The MakerBot Replicatorâ„¢.

Run it!

You can run the application by double clicking the ReplicatorG application.

Install on OSX


Java 1.5 comes preinstalled on Mac OS X 10.4 or later, so you won't need to install it yourself.

Python, which the Skeinforge toolpath generator uses to do its magic, is preinstalled on Mac OS X. However, if Python is giving you trouble, you can download and install version 2.7.2 from

Copy to Applications

  1. Mount the .dmg file.
  2. Create a new subdirectory in Applications to contain ReplicatorG and all its parts. Call it replicatorg.
  3. Select all the contents of the mounted .dmg file and copy them into you new replicatorg folder in Applications.

Note: If you try to run ReplicatorG directly from the mounted disk image, it will complain about running from a read-only directory and exit. Likewise, if you copy only the file from the image and not the rest of the image contents, you will not be able to run the application.

Install Drivers

There is a /drivers folder in the replicatorg folder you installed. It contains a driver for the FTDI USB->Serial converter used with Arduino and Sanguino boards. If you have already installed Arduino, you can skip this step. Otherwise, please install it.

Run it

You can run the ReplicatorG application by double clicking the ReplicatorG icon.

Install on Linux


You'll need to install a recent version of Java (1.5 or later), python 2.6 or later, and the python TkInter package. Additionally, you can speed up toolpath generation by installing the Python "psyco" package.

If you're using Ubuntu or a similar system, you can install all these from the command line:

sudo apt-get install openjdk-6-jdk python python-tk python-psyco

For Ubuntu 11.04 (natty narwhal)

If the model preview window doesn't display properly, you will need to install a proprietary version of Java. To do so, copy and paste this into a terminal:

sudo add-apt-repository "deb natty partner"
sudo apt-get update
sudo apt-get install sun-java6-jre

Next, you need to configure your system to use this version of java. Copy this into a terminal:

sudo update-alternatives --config java

Select the '/usr/lib/jvm/java-6-sun/jre/bin/java' option (it should be option 2)

If you are using KDE and ReplicatorG crashes on startup, add the following line to the file '/usr/lib/jvm/java-6-sun/jre/lib/':

This line is needed because the GTK look and feel does not work with KDE.

For Ubuntu 12.04 LTS

As for Ubuntu 11.04, it's necessary to install a proprietary version of Java if the model preview window doesn't display properly.

To do so, copy and paste this into a terminal:

sudo apt-add-repository ppa:ferramroberto/java
sudo apt-get update
sudo apt-get install sun-java6-jre sun-java6-plugin

Next, you need to configure your system to use this version of java. Copy this into a terminal:

sudo update-alternatives --config java

Select the '/usr/lib/jvm/java-6-sun/jre/bin/java' option (it should be option 2)

Note: If this repository is unavailable, you can also install directly from Oracle's official Java distribution. See instructions here:

If you're still having trouble installing Java, see the instructions at

Optional: remove brltty

Some users have had issues with a Braille program that comes pre-installed in Ubuntu and may conflict with the serial driver. If you run into problems, you can remove the program with this command:

sudo apt-get remove brltty

Unpack it

Unpack the ReplicatorG .tar.gz file to a folder on your desktop (or wherever you'd like to install it).

For Fedora 14 and higher

ReplicatorG 25 ships an older version of the rxtx-library which can cause trouble:

check_group_uucp(): error testing lock file creation
Error details:Permission denied
check_lock_status: No permission to create lock file.

If this happens, replace the library from the replicatorg folder (replicatorg-0025/lib-i686/ with the one from your system (/usr/lib/rxtx/librxtxSerial-*.*.so.) Change the paths accordingly if you are on a 64bit system. (replicatorg-0025/lib-x86_64 and /usr/lib64/rxtx/)

See for more details on this issue.

For Archlinux

Packages requirements

# pacman -Syu python tk

Java version

Unfortunately the model preview doesn't work with openjdk. Oracle proprietary version is required.
You can install it from AUR using jre and jdk packages.

If you have installed aurget then you can simply type

$ aurget -S jre jdk

Access to serial port

Ensure your user have access to the serial port. Check rights on the file /dev/ttyUSBX (if you are using a FTDI usb-serial adapter, where X is the number of the corresponding serial port)

$ ls -la /dev/ttyUSB0
crw-rw---- 1 root uucp 4, 64 Oct  4 08:47 /dev/ttyUSB0

User root and group uucp have read/write access to the device.
In this example, you can simply add your user in the group uucp by editing file /etc/group or using your favorite GUI.

You will probably need to logout/login to update paths and rights.

Run It!

Open the replicatorg folder and run the "replicatorg" script by double-clicking it.

Update Firware

You'll be using the built-in firmware uploader in ReplicatorG to update the firmware on the boards. Once you have ReplicatorG installed, can upgrade to the latest version.

Install the Firmware on the MakerBot Motherboard

Prepare the MakerBot Motherboard

Disconnect any other USB serial devices your computer's USB ports. Next, attach the Thingomatic Arduino MEGA to your computer with the USB cable. If you have already created the MakerBot Motherboard v2.4 Stack which locks the Arduino MEGA to the bottom of the MakerBot Motherboard PCB, then you will use the MakerBot Motherboard v2.4 reset button instead of the one on the Arduino MEGA when the directions call for this action. Otherwise the directions for both route are identical.


Installing the firmware

Start ReplicatorG and Select "Machines > Update Firmware…" from the menu.


Select the board and version you're updating.

Please note: that there is a new, separate set of firmware for the Gen4 Motherboard with Arduino 2560.


Select the version of the firmware you'd like to upload.

This should ordinarily be the one with the highest number, which is the latest version.


Select the serial port that represents your Motherboard.

Your Motherboard will appear as a serial port on your computer. Usually this will be the last one listed. The names will vary from platform to platform.


Upload The Firmware

This is the tricky step. Try to press the reset button at the same time as you click the upload button.

Be patient; it may take a minute or two to upload the firmware. If the upload succeeded, you should see a message indicating success. If you see a message indicating failure, try again! Getting the timing of the reset is important; it may take a few tries to get right.


Install the Firmware on the Extruder Controller

Prepare the Extruder Board

Disconnect your MakerBot Motherboard from your computer's USB port. Now, attach the Extruder Controller v3.6 to your computer with the USB cable. You're ready to go!


Installing the firmware

Start ReplicatorG. and Select "Machines > Update Firmware…" from the menu.


Select the board and version you're updating.


Select the version of the firmware you'd like to upload.

This should ordinarily be the one with the highest number, which is the latest version.


Select the serial port that represents your Extruder Controller.

Your Extruder Controller will appear as a serial port on your computer. Usually this will be the last one listed. The names will vary from platform to platform.


Click on the upload button.

You should not have to manually press the reset button on the Extruder Controller.

Be patient; it may take a minute or two to upload the firmware. When you're done, you should see a message indicating success.


Extruder Testing

Connect your machine

Ensure your extruder controller is connected to your Motherboard, that the ATX power supply is on, and that your electronics are connected to you computer. Fire up ReplicatorG and open the control panel. Select the machine driver appropriate for your machine. It will be in the format of "Thingomatic…Stepstruder MK6."

Test motor

Enter 2 for motor RPM. Turn the motor on forwards. Turn the motor on backwards. Turn the motor off. It should do what you tell it. When it rotates forward, it should rotate clockwise. If it rotates backwards, your stepper motor is probably plugged in backwards. If that's not the case, make sure that Invert A axis is not checked in Motherboard Onboard Preferences.

Test fan

Ensure your extruder fan functions. In the Control Panel Click enable.The extruder fan should run whenever your extruder motor is enabled.

Test thermocouple

Your "Current Temperature" should read approximately 23 degrees C.

Test heater

Warning: The hot end will smoke for a couple minutes as the lubricating oil burns off. Try not to breathe this in and keep in mind that it is a temporary thing. Once it burns off, no more smoke should come off the stepstruder.

Set the heater to 50 C. The temperature should start rising slowly. If the heater is working properly, then set the temperature to 220C.

Test extrusion

While keeping the temperature at 220C, take some ABS filament and push it down into the extruder. Push it all the way down and you should see it extrude out the nozzle tip. If so, you're ready to try motorized extrusion.

Tighten the thumb screw down until the plunger bites down on the ABS. It takes a bit of getting used to, but the plunger system is very forgiving of different settings. Do not over-tighten the thumb screw. If you are really exerting yourself, you are setting it too tight. Tighten it until it gets nice and solid. If during the running of the extruder, you notice the ABS is getting flattened or white stress lines are forming, you have it set too tight. You can back it off during extrusion very easily. Likewise, if it is not tight enough, you can very simply tighten it more until the extrusion stops slipping.

Set the motor RPM to 2 and the motor direction to forward. You should notice the motor kick on, and the extruder should start extruding. Let it run for a few minutes and marvel at your awesome new extruder that you will come to love and cherish.


Daily Printing Operation

Replacing the filament

The basic process to replace the filament is:

  1. Heat up extruder to operating temperature
  2. Loosen the thumb screw tensioner
  3. Quickly pull out old filament by hand
  4. Insert new filament and push it all the way down.
  5. Tighten thumb screw
  6. Turn extruder motor on forward
  7. Wait for extrusion

This process is really simple. If you get good at it, you could even do it while the machine was printing and have an object that is made from multiple colors. Make sure you pull the filament out by hand and not by reversing the extruder. The melted plastic can jam up the drive gear and you'll have to disassemble the filament drive mechanism to fix it.

Keeping it Clean

It's important to keep your extruder clean for proper functioning. Always make sure you are using clean filament with no dust or debris. You may want to have the filament pass through a rag or something in order to remove the dust from it.

Also, during operation your extruder will probably pick up globs of plastic on the nozzle. These should only be removed when the nozzle is hot with a pair of tweezers. You can use needle nose pliers, but be very careful that you do not clamp the nozzle as you may destroy it accidentally.

Keeping Things Tight

As the extruder runs, the thumb screw tensioner may come loose, or things may settle into a looser configuration. Give it a twist to test how tight it is, and tighten it if necessary. You can also loosen it if necessary while the extruder is running.

The rest of the nuts and bolts should be kept tight, especially the ones holding the heater barrel assembly to the extruder housing. Don't tighten things too much so that the acrylic breaks. A good rule of thumb is 1/4 or 1/3 of a turn past hand-tight.


My Extruder does not report the right temperature.

Reality Check #1: Is your thermocouple actually hooked up?

FIXME: Link to or copy from

Reality Check #2: Is it actually your thermocouple?

FIXME: Update this with corresponding thermocouple information
Your thermistor should have a resistance of ~80K at room temperature. Measure the resistance with a multimeter. If it reads low, like say 6-12 ohms, then you have hooked up the heater to the thermistor port instead. Swap the heater and thermistor (double check the heater resistance to make sure!!!).

If the multimeter reads as a short or as 0 ohms, then your thermistor is shorted. Unfortunately, you're going to have to take apart the heater barrel, pull the thermistor leads apart to fix the short, and then re-assemble it.

If your multimeter reads infinite resistance, or no connection, then one of your connections is bad and you'll need to re-attach the lead wires to the thermistor somehow. This involves taking apart and re-assembling the heater barrel assembly.

My extruder does not heat up.

Reality Check #1: Is your heater hooked up?

The heater wires should be hooked up to the HEATER port on the Extruder Controller.

If that doesn't fix it, make sure that you have your heater hooked up. Measure the resistance between the two ends of the heater wire. It should be around 2.5 ohms. FIXME: Elaborate on heater failure modes here.

My extruder motor is not running.

Reality Check #1: Is your motor hooked up?

The stepper motor should be hooked up to a stepper driver, which again should be connected to Axis A on the Motherboard, as well as to a power supply connector.

My extruder motor is running backwards.

First, make sure that Invert A axis is not checked in Motherboard Onboard Preferences.
If that's not the case your stepper motor is probably plugged in backwards; just plug in the other way around.

My extruder has stopped extruding.

This can be a bit tricky. There are a few tricks / techniques to make it work again. Just be patient and you'll have a working extruder in no time.

New Extruders

If you had your first extrusion, but it stopped shortly afterwards, you might have debris in your extruder nozzle. This happens when you do not properly clean your barrel/nozzle before using it.

The solution is to reverse the filament, cut off all the filament from where it got chewed up and below, and run new filament in. The old filament that you pull out will also pull out most of the junk that is in the extruder. Do this a couple times and it should be totally free of debris. You may even see tiny particles on the surface of the melted filament when you pull it out. If you see that, then that is definitely your problem.

Does pushing on the filament start up extrusion again?

If it starts extrusion again, then awesome. Chances are that the drive gear just chewed up the filament too much and lost traction. If you just had to push for a little bit to start extrusion and then the extruder continued to extrude then that was your problem.

If the extrusion starts, but stops as soon as you stop applying pressure, then most likely your plunger position is not tight enough. Tighten the thumb screw and it should fix it.

Does nothing work to start extrusion?

This could be bad. You may have a really bad blockage in the nozzle. If you're using ABS plastic, then your best bet is to take apart the entire heater barrel / nozzle assembly. You should then soak the nozzle and heater barrel in Acetone overnight. The acetone will dissolve the ABS and you can then thoroughly wash the nozzle / heater barrel to remove the blockage. It may be extreme, but it does work.

Does a test extrusion go okay, but then it stops extruding a few layers into the print?

Observe the temperature graph in ReplicatorG's control panel. When the MK6 heats up, the graph line of the temperature should level off and be flat when it gets to temperature. If you notice that your temperature graph has a sine-wave like rise and fall, going above and below the target temperature, you will need to adjust the PID settings in ReplicatorG -Machine -Extruder Onboard Preferences, drop down menu.

PID settings are 5, 0.05, and 100 respectively.

Here is a page for determining custom PID settings:

You might want to check this makerbot blog entry

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