Printing Checklist
- Get an STL file
- Run STL file through Skeinforge to generate GCode file
- Open ReplicatorG and connect to CupCake CNC
- Position nozzle for printing
- Open GCode file with ReplicatorG
- Say/Yell/Scream 'Fire the MakerBot' in a funny accent.
- Click the 'Build' button.
- Watch as the magic happens.
- Troubleshooting
(alternatively Build From SD Card)
Step 1: Get a Model
In order to print something, you're going to need a digital model of the thing that you want to print. The magic of MakerBot, and digital fabrication in general is that it takes a digital design file and turns it into a real, physical object. So, you'll need to get ahold of one somehow.
There are a few ways of getting a file to print with:
Way #1: 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.
Free 3D Modeling Software
- Blender (GPL)
- Art of Illusion (GPL)
- TopMod3D (GPL)
- Wings3D (GPL)
- StructureSynth (GPL)
- Google SketchUp
Non-free 3D Modeling Software
Way #2: 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:
Thingiverse.com - 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 #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:
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.
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.
Step 2: 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.
If you run OS X check out the free open source SkeinFox (and then you can skip down to the ReplicatorG Section 3): http://wiki.github.com/jmil/SkeinFox
Skeinforge
Currently, the best way of slicing a model is to use the Skeinforge program. Skeinforge used to be bundled with the ReplicatorG driver software, but as of version 0007 is now bundled separately. You can get Skeinforge here. Skeinforge comes 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. Aside from mechanical things, getting the internal Skeinforge model to match your machine is the biggest factor in build quality.
Skeinforge needs 3D models in STL format in order to slice them. If your model is not already in STL format, you can use a program such as Blender to import it and convert it. We've written a page on preparing your model for 3D printing with tips and tricks on converting, fixing, and examining models.
Once you have a file ready to be sliced, open up skeinforge. Click the button labeled 'Skeinforge' and it will pop up a dialog where you can select the file you'd like to slice. Select the file, and skeinforge will immediately start slicing it.
For instructions on configuring Skeinforge settings for your Makerbot, check out this page: Configuring Skeinforge.
Warnings:
- Skeinforge was originally a commandline program, and is still in an early stage as a GUI program. It will 'freeze up' while it slices the object. While this is not ideal, this is just how the program operates for now. Slicing 3D models is a pretty computer-intensive process, so be patient and give it time to work through the model.
- Skeinforge does not function properly on OSX/PowerPC, possibly due to problems with the python install. Some times it generates g code, other times it just locks up and does nothing.
When Skeinforge is done, it will show a dialog called Skeinview which shows you exactly what it intends to print, layer by layer. You can click the up/down buttons to go through each layer consecutively. It's a good idea to go through each layer to double check that it is doing what you want it to do. Sometimes a model will have problems that cause it to think it's inside out or something and it will save you headaches if you check it before you try printing it.
Once Skeinforge successfully slices your model, it will create a GCode file. You'll use this file in the next step to actually print your object.
Step 3: Prepare Your Machine
The software we use to control our MakerBot machines is called ReplicatorG, which is available at http://replicat.org/ 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 USB2TTL cable is plugged into both the computer and your MakerBot.
Next, you'll want to navigate to the 'Machine' menu and select Machine -> Driver -> CupCake CNC. It will then attempt to connect to your machine.
*Unless you are on a Mac, you will now need to hit the 'reset' button on your Motherboard.* As of 0003, you will need to reset the motherboard after you open ReplicatorG every time you open it.
Wait about 15 seconds and it should say something like: Found Firmware: R3G Master v1. 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.
Choose a Build Platform
You can use the acrylic build surface that came with your makerbot, or use standard foam core. Cardboard covered with double sided tape also works extremely well and is very inexpensive (see video).
Position the Print Head
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 simple 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.
Step 4: Start The Print
Now that everything is properly positioned and ready to print, you should open the GCode file that was generated by Skeinforge. ReplicatorG will prompt you to move it to a new folder, so just go along with it. In the future, we'll make it so it can bundle up your model, gcode, and skeinforge prefs in a .zip so you can easily swap them with friends and foes. For now you'll just have a lonely folder with a .gcode file in it. Such is life.
Once the gcode file opens, 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.
Now that you've gotten your excitement out in an audible format, click the 'Build' button. The current Skeinforge software includes a warmup routine to the beginning of every GCode file. Basically, it moves the extruder head up 10mm, turns the heater on to 220C, waits for it to heat up, extrudes for 5 seconds, turns the motor off, and then waits until you tell it that it is ready to print.
Due to the current state of the software and the way it handles buffers, it will ask you if it is ready to print before it is done with warmup. DO NOT CLICK YES UNTIL IT IS ACTUALLY READY Your machine is only ready to print once it has warmed up, extruded a bit and you have removed the plastic it has extruded. Once you remove the plastic it extrudes, then click the 'Yes' button and the machine will begin to print.
The first thing it will build is the raft. The first line segment on the raft is most critical point of time during the build. If the first line segment adheres nicely to the build area, you're pretty much guaranteed that the rest of the build will go smoothly (if your object is buildable.)
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.
Step 5: 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.
Now that you've let it cool, pull the entire build base off the Y stage. Since it is held in by magnets, this is very easy to do. Once you have it in-hand, pull the build base off the Build Platform. Make sure to always put the Build Platform back into the machine, otherwise you may misplace it.
The first thing you'll want to clean up is the 'umbilical cord'. Get an Xacto knife or other sharp implement and cut it off. Be careful! Knives are sharp and dangerous. You'll also want to cut off any threads and other parts that didn't print very well.
Update: a few people have had reported that backing the filament out of the heating tube has helped them have better prints the next time around. Back it out!
After you've cleaned up the model with a knife, its a good idea to sand it. 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.
