The model is designed to have dimensions of 99mm x 99mm and a 20mm overhang on each side, creating a total volume of approximately 130 mL. The calculations are based on the following spreadsheet:

The bioreactor needed to be fabricated in a single 3D print and no support structures were used to save materials and reduce 3D printing time, so the first prototype designed and 3D printed resulted in the following:

The test was successful. The test parameters included a wall thickness of 0.6mm and the use of water-based soft glue instead of a heating plate to bond the model to the printing bed. The printing methods using the heating plate still worked normally. Two experimental models were fur- ther designed to evaluate the convenience during use: 

Option (b) in Figure 13 provides better gripping ability due to its circular contact surface which is much larger than the pointed tip of option (a), so option (b) was 3D printed for testing:

The test was successful in terms of ease of fabrication, however the 3D printer settings needed to be optimized to minimize plastic extrusion when moving the print head in non-3D printed locations. This created small plastic fila- ments along the path of the 3D print head. A more serious problem arose when the 0.6mm wall thickness and 0% in- fill density did not provide enough strength when used, the bioreactor cracked along the layers as shown below: