3D Printer - Mechanical Build

Completed Printer

This is the second in a series of posts describing my adventures with 3D printing, and specifically, with a Prusa I3 RepRap Kit.   The first of the series is here.  A picture of the completed printer is to the right.

Here are the parts, somewhat organized, with the parts list from the kit.   I did not do a complete item, by item, inventory but wish that I had for a number of reasons.   First because I was missing a couple parts and second as it might have helped me avoid at least on mistake!

The first piece to be built was the frame of the y-axis.   Did I mention that at the time of this building 3D Printer Czar had not completed their assembly instructions?   I found some for a Prusa I3 on the web and used them.   Did I mention that one of the characteristics of the open hardware source world of the Prusa that there are multiple versions of the Prusa I3?

Which I discover to my chagrin as I start connecting the box frame for the y-axis.   Note that it is a rectangle and all the rods are the same length on a given side.   Just like the one from the instructions that I found.   Unfortunately not like the one the Czar wanted me to build.   Had I done a good inventory I would have known that the frame was supposed to a longer rod to connect to the back of the support frame and I would not have taken a hack saw to a part that I then had to source a replacement.  Naturally, having assembly instructions, or at least high quality pictures, would have also helped!  Anyway, here is the completed frame with the hot bed platform in place.  Speaking of this platform...it was not exceedingly obvious to me how it was supposed to be mounted to the bearings.   Turns out that it just sits on them and is secured with cable ties.  You can't have too many cable ties of different sizes especially as those in the kit did not fit!

Here is the y-axis with the longer rod replaced and with the y-axis servo in place.   The timing belt has also been installed anchored on the bottom of the car that will drive the hot bed and looping through the y-axis idler at one end and the servo motor at the other end.

Now it was time to start on the x- and z-axis frame.  The three bearings will support the extruder assembly.  

At some point it was going to be necessary to tackle the extruder assembly so I got right on it.   This is the completed extruder ready to be mounted on the x-axis car. 

The major mechanical components of the printer were now complete and needed only to be assembled.   The y-axis carriage slides into the x- and z-axis assembly and is bolted into place.  Finally the acrylic support and stiffening pieces are attached to the x- and z-axis assembly ready for mounting of the power supply and electronics.


Here is the printer with all of the mechanical bits attached.



The next post in this series covers electronics and firmware integration.