Building a Prusa i3 MK2 (or MK2S) 3D printer from the kit is a fun experience but there are a few hints and tips I noted down that might help other builders.
There are many ways this build can go wrong leading to breaking parts or ending up with a bad calibration. But if you are prepared to be patient and methodical, it is immensely rewarding.
Intro – Unbox your Prusa i3 MK2S 3D printer kit
When you open up the box and lay everything out on a table, there is a Wow moment when you realise that when Prusa say ‘kit’ they REALLY mean ‘kit’.
I didn’t count all the pieces but suddenly you are faced with perhaps a couple of hundred individual parts including bolts, washers, nuts, rods, 3D printed parts, motors, electronics, cables, cable wraps and ties, the list goes on…
Take a deep breath and don’t panic.
All of the bags are numbered corresponding to the build step. So group them together so you have everything for step 1, 2, 3 etc in order.
Tip: In addition to the supplied tools you will need a ruler or other tool capable of accurately measuring distances up to 400mm. Some people use digital calipers but I just used a standard ruler.
Tip: Go online and read through the entire build manual before beginning construction. The notes in the manual all make sense but I found that they were short on detail about ‘why’ you were doing something a certain way. So reading ahead really helps to build a picture in your head of how it will all fit together.
Tip: In the online manual people have added comments to nearly all build steps. Read all the comments. Any step with over a dozen comments is one where people have struggled so pay special attention to their experiences to avoid similar issues with your 3D printer build.
Step 1 – Building the Y Axis platform
Unfortunately this first step in building your Prusa i3 MK2 3D printer is also the longest and probably one of the most critical in terms of the required accuracy, and the impact it can have on your ability to successfully calibrate your finished 3D printer.
So leave yourself a full evening for this build of the Y Axis. The build guide suggests 3 hours. I would recommend allowing up to 4 hours, don’t rush to try to finish this step especially if this is the first build you have done.
Tip: When screwing the M10 nuts on to the ends of the Y Axis threaded rods, the manual does not indicate how much of the threaded rod should be sticking out beyond the M10 nut. I think this is a major oversight in the manual. So as a guide, finished printers will have around 1-2mm of threaded rod sticking out the ends of the Y Axis.
Tip: Positioning the belt on the Y Axis belt holder is a step I had to undo and redo several times. The manual is unclear about how much of the belt should be sticking out beyond each side of the belt holder. To save you the same trouble, there should be around two teeth of belt sticking out the first side of the belt holder……………………….
Step 2 – Building the X Axis
Compared to the marathon that is the Y Axis build, the X Axis is a doddle. I don’t know why they don’t build the X Axis first to get you into the flow.
The X Axis is built as a standalone piece, unconnected to the Y Axis.