It was a fun building this thing, but there are many things to care about.
Use a file and fine sanding paper for the inside of the linear bushings if they dont run smooth enough - i had to post process here and there.
It just has been built as smoothly as it could get for now, i just have been using the arm for a first drawing right now.
The Pen Drawer I designed is a little crappy as it doesn't compensate uneven surfaces and forces the pen too much on the paper, so it doesn't yet look as nice as it could.
The electronics is an Arduino Mega 2560 + RAMPS 1.4 Shield with DRV8825 Stepper Drivers, each has all 3 jumpers set for 32x µSteps.
RAMPS+DRV8825 Wiring Diagram
For the pen drawer I only have following connections on my RAMPS Board:
- X Motor @ Z-Carriage-Top
- Y Motor @ Z-Carriage-Bottom
- Z Motor @ Baseplate
- X Endstop @ Endstop-Clip, near the smooth rod
- Y Endstop @ Endstop-Clip, the furthest from center away
- Z Endstop @ Z-Carriage-Bottom
Here is my complete Configuration.h: GitHub/Configuration.h
The Tutorial used for Pen-Drawing GCode Creation: YouTube/Tech2C/Drawing with Fusion360
A little edited GCode_Translator: GitHub/GCode_Translator.py (Currently only contains a fix for gcode lines where only one coordinate of X/Y is given)
At the moment, i send the GCode to the arm via Repetier Host.
First attemps for drawings in the sized 100x100 / 80x80 / 60x60 resulted in an error when translating the coordinates, so currently I am limited to 45x45mm.
- Design a spring-loaded Pen Holder Upgrade to decrease the shaking/scrubbing on the paper -> Clearer drawed lines
- Find out how to reach all angles of the bed and what their cartesian coordinates are / visualize the travelable toolpathes
- Make an electronics compartment and a base platform, currently the arm's base is clamped to the table
- Try a Hotend or Laser Toolhead
- If needed: Improvements on stability