Although the widespread use of 3D printers has made things like linear bearings and leadscrews more common, you still can’t run down to your local big-box hardware store and get them. However, you can get drawer slides and any hobby shop can sell you some RC servos. That and an Arduino can make a simple and easy plotter. Just ask [JimRD]. You can also watch it do its thing in the video below.
Of course, servos aren’t usually what you use in a plotter. But the slides convert the rotation of the servo into linear motion. One servo for X and one for Y is all you need. Another microservo lifts the pen up and down using a hinge you could also get from a hardware store.
Is it pretty? No. Does it do amazing artwork? No, again. But it is the kind of thing you could probably throw together from things you happen to have hanging around, especially if you are about to trash an old desk or cabinet with slides in it.
This would make a great rainy day project. We are suckers for simple plotter projects even though you could just mate a pen to your 3D printer or CNC machine. Those won’t fit your whiteboard, though.
I’m sorry but unless experience is the only thing you want what’s the point in making something that doesn’t make or do anything you want? I don’t know about the rest of you but project ideas are the 1 thing that aren’t in short supply.
I don’t want to be too negative. Sorry. It is interesting. And if the results are good enough for someone’s needs/wants then it’s the perfect project
Kudos for correcting your own negativity:) but I somehow agree with your first comment.
👍
Sometimes the whole point is to learn about the theory behind how the device works through practical experimentation.
No, it won’t outperform the ancient Roland DXY-800A that’s sitting at my feet right now, or the two printers (A3 inkjet and A4 laser) downstairs… but such a project would teach you about how to manipulate servo motors to achieve accurate positioning needed for rendering graphics on paper.
Building it means you get a real-world feel for what limitations a particular mechanical design has.
That in itself, is a worthwhile goal for a project. The fact that this is just done with off-the-shelf mundane parts is a bonus as those same parts can be used for something else when the experiment is finished.
Thank you – you understand.
It’s sort of like the synth I’m working on.
It’s not as good as the Stylophone I already have, and it won’t outperform any DAW already running on my PC. However, the project has taught me more about analog electronics than I learned in college, and it’s been fun to build and fun to play.
Projects don’t need to be better or novel or innovative. Building something for fun has value in itself.
Totally agree. And we don’t all have a 3D printer and there is a certain joy in Macguyvering.
For me, i often build similar stuff to just pass time. They end up totally useless but I still feel accomplished. Doing something with hands and brain lets you relax. Hacks like these don’t require much commitment, which is great, for people like me at least.
It does a very good job of demonstrating a generic X-|Y-Z machine – cheaply. In my eyes that makes it a winner.
Oops, spot the typo.
👍
I dig this. I’m a painter, I like that he’s sketching with his crude machine to what equates to painting over someone (or a thing) else’s sketch. That’s a style that that’s pretty neat and unique. Like if you gave me a better sketch from a better pen plotter, I could paint ya something convincingly realistic. This thing? It’s different and that counts, wish I had/could have made that machine myself.
Man they just don’t get us artists. Thank you.
The servos should be mounted lower so the connecting rods stay as parallel as possible to the linear motion, and the strings should attach to the pen carriage, not the servo arm, so as to also address play in the connecting rod joints.
Thanks, will give it a try.
I worked at Calcomp, a pioneer in digital plotters, for 30 years. I loved this.
❤
Attach backlash compensation directly to carriage instead of arms. It will work much better that way! Was the trigonometric approach not suitable?
Thanks, I will give it a try. Also I noticed the single rail that holds the pen is torquing a bit so it loses some precision there. Tried the trigm not sure what I was doing wrong. So I moved on to the polynomial approach and it is close, not perfect.
Love it. Nice touch with the wire nut, also the board with multiple holes in it, sign of making stuff. Lessons learned, priceless. Nice work. Side note, saw some paintings in a store, semi-generic stuff, one of a cow head and another of a pigs head, abstract like. I could see where this….play in the machine really could be quite useful for producing some original works for you. If a pigs head can generate some income, I’m sure one can come up with something original to potentially earn some money, if that is a goal.
👍😊
As a word of encouragement, not saying you need it, those two pictures I mentioned plus a third cow head picture that wasn’t As abstract, I sold them all today, as I work in the store I mentioned. I really wasn’t expecting them to sell so quickly. Good lunch with your endeavors.
Oof, I forget to mention that they were on canvas if that helps.
Gratifying to make sales. This is just a different direction in my art hobby. Will give Processing a try and I was thinking of using a pen mouse and sketch directly with the plotter. Lots of avenues to pursue. Thanks.
@jim Maybe you could use those cheap calipers with UART readout to do autocalibration.
Something like this for example: https://hackaday.com/2011/11/09/talking-digital-calipers-make-engineering-more-accessible/
I have some of those, not the talking variety though. I’m not sure how to translate the print bed coordinates into the servo microseconds though without just poking numbers into my program and seeing where they print. If it prints short of a centimeter, I just add a few microseconds to the servo and try again. Very laborious. After a few hours of piddling, I finally take the approximate numbers and get a polynomial where I can calculate the position based on the curve and plot it. Perhaps I will give the trig another shot as that should not require taking any measurements. I think I failed the first time because I used some really cheap and worn analog servos that did not have accurate servo positions. Now that I have the digital ones the trig calculations might work. Perhaps I am misunderstanding how to use the calipers.
my line of thinking was to attach the calipers to the drawer slide and read it out via the microcontroller (or what have you), then send commands to the servo and read back the position from the calipers
this should be rather easy to automate, provided you can get to the RS232/UART interface on the calipers of course
Jim, love the drawer slides and hinge ideas. You inspire me to try something similar.
If you could use a wheel (or attach a circular sector on that motor arm) working a tensioned loop of fishing line or such, I think you’d just get so many mm of string travel per microseconds (degrees? Time? ) over the entire arc of the motion. No trig /polynomial headaches . (No offense meant to the mathematicians). Just use non stretchy string!
When you say stepper motors, do you mean stepper motors with pulleys and belts? Or driving threaded rod in a nut?