Ender 3 V2 Pen Holder Plotter Bolt On no disassembly

I bought an Ender 3 V2 with the sole intent to modify it to do more than just 3D printing. One of my first goals was to build a plotter for making drawings or sketches. I initially secured a pen to the print head with three rubber bands just to get it working as a plotter. Once I figured out how to create the gcode from an image and had it working as a plotter it was time to make it more user friendly. Unfortunately there weren’t really any pen holders designed to work with the Ender 3 V2 and many were overly complex. I wanted something simple that I could get working quickly that I could change my pen colors without having to redo the XY offsets on everytime I switched colors.

I couldn’t find a design to use with the V2 that I liked so I opened up SOLIDWORKS and grabbed my calipers. After looking over the V2 print head I noticed that there were two threaded screw holes that weren’t currently being used in an area that had enough space to hold a pen.

My first design idea was way too complicated so I scrapped it for a single bolt on plastic part, a rubber band, and two M3x10 hex head screws. The first version of this I did worked great except it was 1mm to high. I lowered it and made some changes to make printing easier (no supports, the first one had supports). Low and behold this beauty was the result! If I make a newer version it will be to thicken the wall around the screw heads so it has a cleaner looking print.

This is designed to work with TRU RED branded pens that I bought at Staples. They’re ~10mm in diameter with straight sides and don’t have a rubberized grip so they’re easy to use from the box. The print is designed to let them slide right in and then you secure it with a rubber band. The long cylinder helps prevent excess lateral wobble and the rubber band provides downward pressure but allows the pen to lift up so it’s not pressing into the paper to hard. This keeps you from having to have “perfect” alignment.

I won’t go into how to generate the gcode for creating sketches but I will address the offsets needed to run right.

The X offset is ~40mm and the Y offset is ~5mm. Using these has worked so well for me that I haven’t felt the need to get the exact offsets. They’re also easy to remember and use.

As for plotting when you want to draw place the print head offset for Z at 1mm and 5mm when you’re not drawing. I had it only lifting 2-3mm initially because it was faster but if the paper starts to curl from moisture from all of the ink it started touching and putting lines in places I didn’t want them. Your Z offset may vary based on where you positioned your sensor but this worked well for me and prevents collisions from occurring with the print head or the holder. You can leave it on when you 3D print. It doesn’t get too hot where it’s positioned and can be printed in PLA. I could probably leave a pen in it as long as the ball point is retracted during 3D printing but I just remove it.

It’s really easy to use. I’ll run one pass in a certain color, then swap colors and do another pass. Swapping the pens takes very little time and effort and there’s no need to have a complicated auto-swap system or the gcode for it. I do all of my colors as separate files and let it auto home between swaps.