zermak3r

a slightly modified Ender-3

The Ender-3 is a fully Open Source 3D printer as Creality3D claims. It means that you have full access to the machine and its hardware parts.

I am playing with my Ender-3 since the day I’ve received it. It’s my first 3D printer and I was very happy with the half-printed¹ dog (available as a GCODE file in the micro SD card sold with the printer) that came out of it considering what I was seeing online, while I was waiting the delivery, trying to get as much informations about 3D printing as I could.

My first modification was the replacement of the bed pad with a 3mm thick 235x235mm glass.

When I finally received the one kilogram of PLA’s filament I started printing a few objects to improve the printer itself. I printed the cable management’s chains to make it looks less messy and for safer motions, the filament’s guide to ease the extruder stepper motor’s job and the adjustable endstop for the Y-axis to match the physical zero with the front-start of the bed.

Before every print I found myself leveling the bed with the hand twisted nuts using the LCD controls and then with my own interactive GCODE, to move the nozzle close to the corners and onto the bed.

This procedure was slow and annoying but it made me realize that the springs used to hold the bed in place were underdimensioned or just loose for their job. In fact to have a steady bed the springs were almost totally squeezed with pratically no margins to adjust the bed properly.

The bad part was that I couldn’t even use the printer in that way because the little space between the bed plate and its support were messing with the bed heater cables so I had to find a workaround. Indeed I’ve designed and then printed four solid blocks (with a hole in the middle for the screw) to install between the bed support and the spings to stiffen the latter and to keep a good amout of space between bed plate and its support.

Raspberry Pi 3 Model B plus and OctoPrint part, coming soon.

As said before the manual leveling procedure wasn’t very friendly and fast so the next step was to get a probe for the job to enable the auto bed leveling procedure on Marlin.
After some researches I chose to go with a genuine BLTouch because of its ability to work on every bed material (after all I was using glass) and its good reliability.

To use it I had to print the mount for it first and then solder some cables and pins because of the short length of the original cable.

The installation wasn’t easy but I took my time to do a decent job and to run the cables properly.

The guide I read to make it work was good but I had to use my basic electonical skills to work it out because I wasn’t using the PIN27 adapter moreover the firmware part was missing something (I don’t know how it is now, I haven’t used it since and I can kinda configure my own Marlin firmware now) or didn’t explain how to solve a few errors you can receive while compiling the new firmware but thankfully internet is resourcefull and back then I was able to overcome them with a few researches.

With the BLTouch installed printing is funnier but I check the mechanical bed leveling once in a while.

Meshing your bed with a probe is cool but if your Z-axis can’t keep up with it in terms of precision then it’s not so worth the money (indeed I was able to have great prints on glass with the manual bed leveling).

The next natural step was the replacement of the Z threaded rod (a T8x8, meaning every turn it moves 8mm up/down) with something else. I picked up a T8x2 (2mm per turn) making the Z-axis four times more precise than the original. In plain numbers it means that the Z-axis could move by 0,000625mm with the original NEMA17 motor (1.8° per step) and the original microstepping driver (1⁄16) and it can move by 0,01mm (10μm) in full step mode.
You can actually see how much the Z stepper motor works now.

To be continued…

¹ delivery was really fast and I found myself without any filament to test it so I had to use the very short filament sample in the Ender-3 package