How To Print

This page is an overview of turning a thought into an object.

Printing Overview

The magic of MakerBot – and digital fabrication in general – is that it takes a model, a digital design, and turns it into a real, physical object.

The designs are files in .STL format, which is short for STereoLithography. These files describe the surface geometry of a 3D object.

There are a three ways of getting a file to print with:

  1. Use an existing file. Easiest and probably best for your first print!
  2. Design a model yourself in CAD software. Great once you've learned how.
  3. Scan a real-life object. Fun and probably not as hard as you'd think.

Details on these three methods are given below. All are available in open source versions, so you'll be able to find them on the Internet and find communities of people to advise and help.

Once you've loaded the .stl file, the model needs to be "sliced", or turned into a set of print layers. Don't worry, it's as easy as clicking a button! In this case, SkeinForge, which is incorporated into ReplicatorG, does the slicing and turns the model into gcode. The gcode tells the makerbot how to print the object.

Basic Steps in Printing

  1. Get an STL file
  2. Open ReplicatorG and connect to your Thing-O-Matic or CupCake CNC
  3. Open the STL file in ReplicatorG
  4. Run STL file through Skeinforge to generate GCode file
  5. Position nozzle for printing (Cupcake only)
  6. Say/Yell/Scream 'Fire the MakerBot' in a funny accent.
  7. Click the 'Build' button.
  8. Watch as the magic happen.
  9. Troubleshooting (in case the magic fizzles).

Step 1: Get a Model


Way #1: Download from the Internet


If you don't have 3D modeling skills, this is probably the fastest way to get a design to print. It's also the coolest. In a way, you're downloading an object from the internet and your machine is simply making it real. Just like the internet has revolutionized the way we listen to music and watch movies, it will soon revolutionize the way we use objects. Now you're on the forefront of that movement too.

So, where do you go to get 3D models? That's a good question. There are a few places you can go: - This is a site we created for people to share their digital designs for physical objects. There are a ton of 3D printable files up on the site, and more are added every day. It is a community of like-minded people who love both digital fabrication and sharing.

Sketchup - This is Googles 3D design warehouse. You'll have to dig for things that are intended for printing, as there are a ton of non-printable designs up on their site. Its also quite tricky to extract usable 3D data from their files, but it is possible.

Way #2:

Design it yourself


This is probably the coolest route. It is also the hardest route. Most 3D modeling programs have a fairly steep learning curve that can be intimidating to beginners. Don't worry though, its not too bad. It may take you a few attempts with a tutorial, but you can definitely learn how to do it if you really want to. That's what makes you a human!

There are a huge number of 3D design programs available, both free and non-free. Here is a short list of programs that we've either used or been recommended.

If you plan on designing your own models, check out our guidelines for designers.

We are collecting tutorials making a 3d logo from a 2d bitmap/EPS file. One uses Gimp, Inkscape and Blender. If you have an tutorial, link it in here!

Free 3D Modeling Software

Non-free 3D Modeling Software

Way #3: Scan a real object


This may be one of the coolest untapped methods for getting 3D models to print. Basically you just get a real object that exists, you scan it, and then you print it. Thats it. With this you don't just have a machine that can make anything, you have a machine that can copy anything. That is a powerful thing.

The hardest part is actually scanning in the object. There are quite a few different ways of doing this. Some are open/free projects, and there are also commercial 3D scanners that are pretty nice. Here is a short list:

Makerbot 3d Scanner - You might already know about the MakerBot 3d scanner. This is basically a nice little kit which allows you to use a normal consumer pico projector and webcam or other camera to make 3d scans of small objects.

NextEngine - This is pretty much the hottest 3D scanner out there right now. It's $3000, but it does amazingly accurate scans, and it looks to be pretty simple to use. This is what we're drooling over here at MakerBot these days.

David 3D Scanner - This is a sort-of open source 3D scanner. It uses a webcam and a handheld laser to allow you to scan in objects. They charge for the deluxe versions of the software, and also for kits to build your own 3D scanner. The kit currently runs at about $725 for the supplies to build your own.

Tgi3D PhotoScan – This is a software-based 3D scanning method. Compared to laser scanners it is much more affordable and it is very accurate. You can use any digital camera to get your 3D model and you don’t have to set up anything while capturing your photos, unlike laser scanners. Just take pictures of your object from different angles and use the software for 3D modeling with Google SketchUp. Give it a try!

Step 1B: Clean Your Model!

It's pretty easy to create a non-printable 3D model, especially if you're using a design you found on the internet. Being able to clean up a model and fix it to be printable is a very valuable skill to possess. There are a couple tools that are great for model cleaning.

Cleanup with Blender

A few UI tips:

  • the 'A' key toggles between select all and select none
  • the right key is how you select objects
  • the tab key will take you between object and mesh mode
  • holding middle click will allow you to move your view. scrolling it will zoom.
  • the num pad keys will give you good default views if you get lost
  • the 'X' key will allow you to delete objects, like the default cube when you open blender

Import / Export

Blender supports a TON of import and export formats. You'll want to export your final object as STL for printing though.

Remove duplicate vertices

1. Hit Tab to enter Mesh Edit mode
2. Hit A to select all nodes (everything goes yellow and purple)
3. Type W6 or select Mesh -> Vertices -> Remove Doubles

Find non-manifold points

Non-manifold points are points that just don't make sense in the real world. These can be hanging points, internal surfaces, holes, zero-thickness walls, etc. Unfortunately there is no way to automatically fix them in software. The best you can do is to identify the problems and then attempt to fix them.

1. Hit Tab to enter Mesh Edit mode
2. Hit A to deselect all nodes (everything goes gray and pink)
3. Select Select -> Non-Manifold

If there are non-manifold points, they will be selected. If nothing happens, you're golden. If there are problems, then you can see what's wrong and attempt to fix it.

Clean STL file with netfabb - alternative to blender easy automated tool-

netfabb studio basic is free
1. open file in netfabb
2. click red cross - top right tool bar
3. click update button right side mid way down
4. click automatic repair button bottom right
5. click update again to make sure it fixed everything
6. if ok click apply repair bottom right
7. export file by right clicking part file name in box right top side, select export and file type which is STL
8. export window select path and file name, STL format binary STL, then click ok

netfabb is an easy automated way to fix manifold and other mesh errors quickly.

Step 2: Open ReplicatorG and prepare your machine


The software we use to control our MakerBot machines is called ReplicatorG, which is available at This software takes a GCode file and then talks to the electronics that control your machine and tell it exactly what to do. Obviously you'll need to have ReplicatorG installed and configured before you can use it.

First, open ReplicatorG. Make sure you have your MakerBot plugged in and turned on. You should also double check that your USB or USB2TTL cable is plugged into both the computer and your MakerBot.

Next, you'll want to navigate to the 'Machine' menu and select the proper driver for your machine. Make sure you make the proper selections for Thing-O-matic/Cupcake, Non-heated, Heated, or Automated Build Platforms, and MK5 or MK6 extruder.

Now you can hit the "Connect" button in the top of the window, and hopefully you'll see a few messages in reassuring yellow text down in the console, something like:
Motherboard firmware v2.8 (Motherboard)
Toolhead 0: Extruder controller firmware v2.8 (Extruder)
When that comes up, you know that ReplicatorG has found your MakerBot and is ready to print. At this point in time you can do various things like open the Control Panel, or start your build. If you see any scary red messages, you might want to head to troubleshooting.

Step 3: Slice Your Model

Once you have a 3D model, you need to run it through a slicer to generate GCode, which is the file format that you send to the printer that tells it exactly what it needs to do in order to build your object. Skeinforge is the current slicer.



Currently, the best way of slicing a model is to use Skeinforge. You can get Skeinforge here. Skeinforge is bundled with the latest MakerBot configuration settings, so it should generate usable GCode right out of the box. You can also get the latest settings here. Tuning Skeinforge to match your machine is the most important factor in getting high quality prints. This will take time and patience so keep in mind the community is here (google group) to help you.

Luckily, Skeinforge is integrated into ReplicatorG! Open your .stl file right in ReplicatorG, and you'll see a 3d view of the model, where you can move/center/resize the object as necessary. When that's all to your taste, save your model and click the "Generate Gcode" button in the lower-right corner of the screen. That will open up a dialog box with some built-in profiles for common bot configurations. If you need to tweak settings, you can select one of those and click the "Edit" button to get right into Skeinforge.

Step 4: Position the Print Head (Cupcake Only)

The Thing-O-Matic has automated homing before builds, so if you're a Thing-O-Matic user, you can skip this step!

Before you start your build though, you need to position the head for printing. The way Skeinforge operates is that it centers the model at (0,0) in the XY plane and drops the model to Z=0. So even if your model is wildly off-center in the digital file, it will be re-centered in the GCode file that Skeinforge generates.

What that means, is that you need to position the print head in the middle of the build platform and wherever you position the print head, that is where the middle of the printed object will be. You will also need to bring the extruder head down so that it almost (but doesn't quite) touch the build surface.

There are a few ways of doing this, and it is one of the things that we'll be automating REAL SOON NOW.

The first, and simplest way of doing it is to move the build platform manually. First, position the X stage by moving it. If it doesn't slide easily, check to see if your stepper motors are on. If they are, simply turn the switch on the motherboard to 'off'. This only turns power off to the motors and such, but the motherboard remains connected to your computer. If the motherboard has recently been reset, the motors will be off so usually you won't have to do this.

Once the motors are off, you can then move the X/Y stage freely. If you use the lasercut build bases that we have supplied, then things are easy: there is a tiny circle laser etched into the middle of the build base. Simply position the nozzle over this and your X/Y stage is centered.

The Z stage is also pretty easy. The simplest and fastest way to position it is to grab the Z belt on the rear of the machine and move it so that the Z stage moves up and down. Once you position the head close to the build platform, you can use the Z motor pulley as a fine adjustment knob to get it just right.

The trick to positioning the nozzle is to take it so that it just barely 'kisses' the build surface and then raise it up a bit. Generally you want it to be about 1/2 the diameter of the extruded filament above the build surface. You'll be practicing this many times as you print, and it is not extremely critical that you get it perfect, as you'll find out later. Just try to get it close and then go from there.

Once your nozzle is positioned properly you're ready to start the print.

Steps 5-7: Start The Print


Now that everything is properly positioned and ready to print, you should click on the gcode tab within ReplicatorG to check out the code that's been generated! It might not mean a lot to you now, but it's actually very simple and easy to read.
Now that you've generated your gcode, you are almost ready to print. Do a quick systems check that everything is right:

  • ReplicatorG connected to electronics.
  • Motherboard / Steppers / Extruder have power LEDs on.
  • Extruder positioned properly.

If everything checks out, then you'll need to yell your battle cry. We like to say "Fire the MakerBot", but you can make up your own if you like. This is a momentous event and it should be marked by something classy, cheesy, or just awesome. Take time to make it yours.

It is recommended that the extruder warm up (just set the heater @220C in ReplicatorG's control panel; don't run the motor) for a good 5-10 minutes before attempting a first noodle when starting from cold. After it's warmed up, some prefer to "idle" at about 160C between builds. It's cold enough that the nozzle doesn't ooze and you're less likely to get a rising pool of molten ABS in the barrel.

Now that you've gotten your excitement out in an audible format, click the 'Build' button. If you're using a Thing-O-Matic, this will start the homing code, which takes the print head to the Z-maximum, and the build platform the X- and Y-minimum; then it will move the print head near the wiper nozzle and wait until it reaches printing temperature. The Cupcake won't do the homing, but it will move the head to a waiting position while it heats.

The first thing it will build is the raft. (Unless you're printing raftless, but if you're doing that, you're probably too advanced for this guide…)

There are a few things that can go wrong during raft printing, so check out the troubleshooting area for help on how to fix them.

Building From SD Card

Many people get better results and less build hiccups by building from an SD card on the motherboard. This often helps with blobs, miss-feeds, etc. especially if you have lots of short runs (eg. zig zag fills). Another benefit from this method is that you can start a print, unplug your computer/laptop from the machine and have it print "headless".

Step N+1: Finishing Up


Once your print has completed, you'll want to take your object out immediately. You should resist that temptation for at least a minute or two though. ABS plastic tends to cool almost immediately which is nice, but the last few layers tend to be a bit malleable right after the print is done, especially if they are small and detailed. If you have an Automated Build Platform, your machine will monitor the temperature and eject the part when it's cooled sufficiently. If you have any other configuration, you'll have to decide how long to wait.

After that, you can clean up the model with a knife, or even sand it for a smoother surface. Start with something like a 200 grit sandpaper, and work your way up. You can get really good results with only a little bit of effort. ABS plastic sands really well, but try not to breathe in the dust. You can use a heat gun to turn the little white bits back to the same color as the rest of your print.


See: troubleshooting.

Unless otherwise stated, the content of this page is licensed under GNU Free Documentation License.