First 3D Printer

Three 3D printers as above have been acquired and a large one capable of 400mm x 400mmm x 500mm prints with dual head. The smaller printer prone to jamming because the linear bearings are impossible to assemble correctly aligned due to a design mistake. An option is to design and print replacement parts for the linear bearings before trying to assemble the remaining printers. The large printer arrived with borosilicate glass plate broken. Local replacement supplier found that can make the 400mm x 400mm x 3mm thick borosilicate glass. The dual head printer was chosen because one head can print ABS while the other prints PVA, a water soluble support material. The support material is dissolved away with water speeding up the 3D printing process which would otherwise require a lot of time to remove support material. The software running on the PC is Repetier running under Linux which connects through USB to the controller board on the 3D printer. The control board is an Arduino. The power supply that comes with the printer was determined to be weak, so a bench power supply capable of sourcing ample current at 15V was used.

Parametric Chucks

Sample parametric chucks printed on 3D printer. These were specially developed in OpenSCAD to make custom machines easy to fabricate with custom profiles and chucks. The opening to the chuck can be customized to any size round shape or a polygon shape such as those on a hex bit, or any profile such as an L shape. The chuck uses an angled helix screw thread so that the angle of the screw does not line up with print layers which makes the screw and nut assembly extremely tough to pull apart. These 3D printed PLA nuts can be tightened with a spanner :) - may be we try to print some olives as well to see if they can be used for cold tap water copper pipes at 3 bar pressure (hot water will soften the PLA and fail under pressure).  (Ordinary threads may peel away when the nut is tightened if print layer is parallel to the thread.) We can also now do custom angled gears with a chuck lock to lock the gear wheel to any shaft. It is an interesting way to lock gear wheels to shafts and prototype new mechanisms rapidly if the mechanism is too awkward to print.