This project is the largest I have ever undertaken, and its goal is multifold. Besides the obvious benefits of having a 3D printer, it has taught me a lot of valuable information as a designer. The most recent lesson it taught me was how errors in the initial stages can result in compounded errors later.
While designing the rough CAD layout for Eta, I placed the XY steppers on both “legs” of the H formed by the X&Y rods, as it should be. However, I later rotated all smooth rod axes vertically to facilitate easier access to the printing surface from the front. At the time, I didn’t think there could be any conflict, but after around 5 months when I finally finished making, aligning, and bolting down all the axes, motors and mounts, I realized that this arrangement meant that the motors were countering each other’s movement.
You done goofed.
Since both motors were on the same side, one of them turning would have prevented the other one turning in the opposite direction. To correct this, I swapped the motor on left with the idler mount diagonally opposite, which fixed the issue. The problem with large or long duration projects such as this is that you tend to sometimes lose focus of your original goal, or change a system without realizing its effects on another system.
Design life lessons aside, I’ve extended and linked up the cables from the hot end, and now all that’s left is to hook up the mechanical endstops, setup the heat bed, make the fail safe systems, create the secondary control board and relay board, and I’m done!
With the hardware section, that is.
Next up, the software, and how I’m attempting to control a 3D printer with a 15 year old desktop jury rigged into working order with string to hold it together. I’m running linux mint on that PC, so at the very least it isn’t too slow.