Mini Plotter and MidSize Plotter

I followed many of the online tutorials and crafted the mini plotter from a couple of scrapped DVD drives and a miniservo. After some experimentation with settings and messing about in some downloaded Tiny CNC Arduino code, I was able to make some mini plots with a standard ink pen. May not be too exciting for the old pros, but I found it fun and educational for an old artist trying to learn new tricks :slight_smile:

My next step was to take a gutted HP1210 printer and swap out the two dc motors with some small 28byj-48 steppers coupled with two L298n motor controller boards. I did cut the middle trace on the little circuit board in the stepper motor to make it act like a bipolar stepper. I made a flexible coupling from a small length of plastic tubing and am driving the paper roller directly. I used the rail with belt drive, but redrilled the small toothed pulley, and used another hacked 28byj-48 to replace the dc motor on the carriage. Once again I used a mini servo as a penlift device.

This build was fairly successful, but since my math and coding skills are virtually non-existent, I have a little trouble reconciling the proportion difference from the rev/mm/steps of the top carriage, and the rev/mm/steps for the direct drive of the paper roller. I did many test prints of 100 or 1000 steps, measuring the distances in mm and plugging numbers back into the Arduino code. I can get it real close this way, but not yet 100%.

I did get another hp deskjet yesterday for $5 usd. I think I am going to use the rails, and carriage to make a moving table version. I have several more little steppers and servos now, and I even puchased some timing gears that fit the shaft of the steppers and some timing belt materials. Hopefully I will not have as much trouble understanding and getting the X-Y proportions right if both are moving the same distance at the same rate. I will post some more pictures of the build once I get a little further into :slight_smile: Meanwhile I consider the first two versions “done enough” and posted here in the Exhibition area. Enjoy!

Here I rebuilt the letter sized plotter. Made it a little more accurate, although I feel I have reached the limit for these small steppers and control boards. I plan on using it for plotting and cutting parts for paper sculptures.



Here is another iteration of the plotter with both a pen holder and a small engraver as an end mill. The mill is experimental still, but the idea is workable. I changed the servo penlift to another small stepper motor with a ULN2003 control board. It's much quiter now.

Here is the little mill running:

And I made another small plotter with some dvdrom drives that seemed to have dc motors for the head control rather than the small steppers:

I rigged it up with some small belts and pulleys from the junked printers :slight_smile: It also uses 24byj-48 steppers and ULN2003 boards.