Tag: axi draw

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Art Generative Art Pen plotting

Useful things to know when using a pen plotter

Pen plotting is a fantastic way to create unique artworks and designs. There are a lot of things to find out and get the hang of, this guide should help. I am using an Axidraw pen plotter, but most advice should be useful for other plotters too.

This was originally planned as a handout after a workshop for pen plotting I wanted to give. It didn’t happen, so maybe other people can learn from it.

People who just got a pen plotter and started to play around, will probably find this most useful.

Checklist before starting a plot

  • Open and check SVG file:
    • Is the correct format set (e.g. A4, landscape)?
    • Are the correct colors enabled/disabled?
    • Check settings (speed, pen height,etc.)
  • Check work area:
    • Is the correct pen inserted and secured?
    • Is the paper flat and nothing hidden under it?
    • Is the paper well fixed?
    • Is there nothing in the way of the plotter arm?
  • Start printing. Ideally, wait until the first lines are drawn to make sure you didn’t miss something.

Things to know when working with a pen-plotter (AxiDraw)

  • The servo motor lifts and lowers the pen, but it does not press onto the paper (use a weight when more pressure is needed)
  • The pen-plotter draws lines, it can’t fill areas like the bucket in paint (use hatching instead).
  • A running plot can only be interrupted with the button on the plotter. You can continue in Inkscape under “Axi Draw Control” → Resume.
  • It is worth making a small test print before starting a 8h plot when trying something new.
  • Servos wear out, it is worth having a reserve, especially when you do plots that take a long time (there is now a new version, which is quieter and lives longer)

Possible problems when plotting

  • Paper is not properly aligned with Plotter. (Draw lines on the surface under the Plotter for orientation)
  • Plotter / Paper / Surface is moving due to the movement of the pen-plotter.
  • Paper roughens up / gets holes from many pen strokes (use stronger paper, different pen, optimize file to reduce repeating lines)
  • When using multiple pens, pay attention to pen diameters (the tips might not have the same position, which might lead to misalignment)
  • Computer goes into sleep mode during print (change the settings on your computer to a longer time)
  • Surface not evenly flat → strokes don’t have the same thickness / darkness
  • Certain pens may need additional weight to draw evenly
  • Different colors can bleed into each other, depending on pen, color sequence matters
Here I used different kinds of pen, which lead to them not properly aligning. Also, I draw the black grid first, which then mixed into the lighter areas.

Pen Selection

  • Pens with hard tips work best, as they don’t wear down and move evenly.
  • Fiber tips (such as Stabilos) wear down depending on the surface.
  • Certain pens will fade over time. (to avoid use pen that are sun proof )
  • With certain pens, the plot speed makes a difference to the result (slow movement, more ink can flow from the pen)
  • For initial CYMK plots (Cyan, Yellow, Magenta), Stabilos are practical for learning and easily available
  • Lead and color pencils are very difficult to use as they require more pressure and wear down fast
  • Two passes when printing can lead to better results (for example, with less reliable pens)
While this is one of my favourites, it’s also an example of a bad pen. The pen did draw quite unreliable. This was lucky in this case, because it gave the whole image texture and a depth it just wouldn’t have otherwise.

Paper selection

  • Generally, all paper works. Cheap paper sometimes looks cheap.
  • Cheap paper tends to tear more easily with multiple passes trough one point.
  • Flatter paper is more reliable with all pens (like printer paper)
  • More expensive paper has a nicer texture, but tends to wear out certain pens more quickly.
  • It doesn’t need to be paper, experiment around, why not try glass, wood or something else (but maybe test first on paper)
  • Printing on fabric is possible, but not easy; it is important to keep the fabric taut for even printing. Detail is limited.
Plot on a Shirt. Original SVG was in a proper circle, it is difficult to put tension on the shirt equally. Choose flexible, log details designs.

How to work with Inkscape (AxiDraw)

  • Through the AxiDraw plugin, the Inkscape becomes an interface for controlling the pen plotter. To start printing in the menu: Extension → Axidraw Control → Apply.
  • Only the lines and groups that are currently visible will be printed (important for using different pens).
  • Optimizing line order leads to faster prints (then pen moves to a close line): Axidraw Utilities → Plot Optimization. Can be activated by default.

Axidraw plugin functions for Inkscape

  • Hershey Text. Better letters for plots. If you use normal fonts, it just draws the outline of the letters (which sometimes works well enough). With Hershey-text, letters are drawn with only one line (not the outline of the letters).
  • Hatching: Plot can only draw lines, not surfaces, but with hatching, you can fill surfaces with lines.
  • Plot Duration Estimation: Axidraw Control → Options → Preview → Enable offline Preview mode → Start normal printing

Useful links and resources