After collecting the parts and studying the drawings and instructions of the Printrbot it's time to start building. Before I got started I realized two things are very important for a 3D-Printer: It must be rigid, and all angles must be exactly 90 degrees. For lengths up to 30 cm the makerbeam seems rigid enough, although in the end I found that if you lift the bottom frame at one end it still deforms slightly. By using only the pre-cut length pieces I made sure all angles 90 degrees and all guides are exactly parallel .
This is the basic frame. Although over time many things have adde and modified, this part has remained basically unchanged.
Fixing the vertical rods,both at the bottom and at the top.
Mounted the Y-Axis stepper motor on a piece of Aluminium L-profile. A frame made from 4 pieces of 100 mm is used as the carrier. Four ball bearings on the side, four on the front to carry the Y-Axis sliders.
The Y-Axis slider is assembled from two rods and some 100, 50 and 40 mm makerbeams. Note that on the photo's most parts are still assembled using Ty-Raps. Later on I replaced most of these with hose clamps, but during the build and test phase this is more flexible.
The print bed will be placed on a frame made from two rods and some 100mm makerbeam pieces. I mounted a piece of 40mm beam to the front of the steppermotor and two 10mm ball bearings to that.