A 3D printer is a three-axis machine, because the title implies. The commonest structure for 3D printers is Cartesian, which implies that every axis strikes independently of the others. Virtually all Cartesian 3D printers have these axes driving on inflexible rails, like hardened metal rods or aluminum extrusion. However that is not a requirement and a 3D printer can abandon the rails and the Cartesian structure altogether. One very fascinating instance is Dizekat’s Marionette 3D printer.
The Marionette 3D printer is extraordinarily distinctive and we have by no means seen a design fairly prefer it. The body of the printer is aluminum extrusion, however virtually all the similarities to a typical 3D printer finish there. The kinematics and mechanical setup share extra in widespread with a cable robotic than the 3D printers on the patron market.
To grasp how this works, lets first have a look at the XY airplane. As an alternative of two units of rails and bearings, the Marionette printer has a easy pane of glass and the extruder carriages strikes round on a slider that contacts the glass. That is inverted, so the glass is on prime and the carriage is pulled up in opposition to it beneath. The friction is low sufficient that it could slide with out concern, so it could transfer freely within the X and Y axes whereas being constrained within the Z axis.
The printer strikes the carriage slider utilizing a pair of motorized spools that alter the lengths of the cables that maintain the carriage in opposition to the glass. Lengthen the left two whereas shortening the proper two, and the carriage will transfer proper on the X axis. Coordinating that motion requires some trigonometry calculations, like with a cable robotic. A fancy 3D-printed mechanism on prime of the glass ensures that the cables preserve correct stress and size, relative to one another.
The Z axis can also be uncommon. The heated mattress raises and lowers utilizing one other pulley system that distributes pressure throughout the 4 sides. And even the recent finish is exclusive, because it sits at an angle relative to the mattress with a 90-degree nozzle.
The electronics appear to be normal fare, although they definitely required customized firmware to translate normal g-code into the required trigonometric actions.
There are numerous potential issues with this design that each one consequence from a scarcity of rigidity and the imprecision of spooled cable. However Dizekat was in a position to print a Pace Benchy in just below 4 minutes — although it appears to be like fairly tough. The first benefit of this Marionette design is value, as linear rails and bearings are dear. It additionally has the potential for high-speed printing, as a result of the transferring carriage could be very light-weight.