Ep.2: design choices, Z axis sizing, the importance of geared reduction
In this episode I (try to) explain the two main ways on how to move the Z axis: push the extruder carriage up or pull the bed down. While usually this doesn't affect the design very much, in this case weight is a huge factor.
(sorry, haven't prepared a script this time)
Also here I show how a previous design choice of having just two motors rotating two 12mm screws with four 8mm smooth steel rods was a failure and why, in the end, the KISS ("keep it simple, stupid!") rule almost always gives the right advice: just the screws but four of them, and no rods.
Lastly, gears! Reduction! Not only it adds torque, wich is ALWAYS a good thing, but also adds precision, wich is extremely important expecially when your prints get uneven layers.
Next time: movement! Motors, drivers, belts, screws. How and why choosing one instead of another.