Shop Adventures Vol. 2

Drawing with bigger pens

The Story

In the dark days of yesteryear , the Graphtec plotter only printed with one pen, a thin, black, felt tip marker. The drawings were colorless, and only consisted of an single, narrow line weight.

Then came the hero, the one called Simon, who modeled and 3d printed a new collet, allowing a new type of pen to grace the plotter’s paper.

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Simon’s Collet accepted pens of many colors, creating beautiful landscapes and drawings full of color and life.

But alas, I was not satisfied, I wanted more. I wanted gel pens and oil markers, sharpies and metallics, I could not be satisfied with just more colors!

So I got to work, prototyping a new design that could hold a pen or marker of any size. The plotter’s attachment points limit the size of the tip if the pen, but I did not let that stop me. Instead I offset the pen, attaching it to Simon’s Collet as a side car. The prototype was hacked together with tape and 2 zip ties, but it worked!

Hurray it worked! I drew a circle, and so I knew I could make this happen. I rushed to find the rhino files and model a new attachment, to hold another pen alongside Simon’s Collet.

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Within the hour I had a shiny new print, capable of holding my metallic markers.

And Did it work? Yes Sir, it worked beautifully. I need to perform further testing, but the initial results are promising. Good Day.

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Shop Adventures Vol. 1

The mystery of the Graphtec plotter

Plotter in Action

Disclaimer:

These are just my observations, I make no claim to facts

Context:

I wanted to use the plotter to draw some posters for my upcoming show. I was printing these out in batches of 10 to minimize color changes, time, and wear on the paper which will disintegrate after too many passes over the rollers. 

Observations: 

• The Graphtec Plotter in dFab seems to have a mind of its own. While it can create beautiful and precise drawings and vinyl cuttings, it’s a seemingly inefficient machine with an unknown sorting algorithm. The machine will start drawing in one area, then move to a location on the other side of the paper to continue, then back again, wasting an enormous amount of time during travel. 
• Parts of my file: 

• Cubes 
  • a collection of mostly open curves, printed first with a yellow marker

• Color 1 – Dominate text Color.
  • Single Line font created as a text object (open cvs)
  • Regular font created as a text object (closed crvs)
  • An exploded hatch of the text shown as an open curves in properties
• Color 2 – Same as color 1 printed in a subordinate color
• While my posters were printing I noticed an interesting phenomenon. On Color 1 and Color 2, The Single Line font, and the font outlines would print first, on all posters with the normal no sorting nonsense. After all other geometry had printed, the plotter would return and print the exploded hatch. So then, there is some logic behind the sort. The likelihood of a random sort separating that many like-geometry is very low.
• To Test this logic, I identified several possible distinctions that separate this geometry from the rest
  • Drawing Order
  • Open/closed Crvs
  • Point count
  • Line type
  • Layer 

Just printing the top row, no layers, the text and outlines is printed before the hatch

Question:

Can I use one of these distinctions to analyze the plotter’s sorting algorithm, and ultimately print my posters faster

Research:

• Past Solutions
  • The quick and dirty fix is to “show” and “hide” geometry to print smaller areas and save machine time. This is annoying and much more user intensive. 
  • So far, the best approach to sorting has been drawing order, in other words, the order in which the geometry was drawn in rhino. With this knowledge, rhino curves can be run through a grasshopper algorithm to sort by distance to a point, then baked out to rhino for a slightly faster operation. This works but is unreliable and still has it’s issues.

Hypothesis:

• The Hatches were “drawn” last when they were exploded, so the plotter sorted them at the end.
  • Still a possibility, although Mckibbin claims to have disproved the drawing order theory. 
• Open/Closed Crvs effect the sorting algorithm
  • At a glance, it may seem like the hatches were printed last since they were open curves and the text is a closed outline. However Color 1 and 2 contained other open curves which were not separated in the same way. 
• Point Count or Line Type (degree, 2 point, exploded from a hatch, etc) effects the sorting algorithm
  • This may still be true, I did not have a quick way to test this hypothesis
• The Geometry’s Layer effects the sorting algorithm
  • At some point in the file’s creation, the hatch was located on another layer. I thought that I may have left the hatch on a separate layer causing it to print last. While this was not the case, it was an interesting hypothesis so I tested it. 

Experiment 1:

• Designing the experiment was simple. For the first operation–Cubes, I placed each poster’s design on a sub-layer labelled 1-10. With all sublayers visible, I sent the file.
• Amazingly, each individual poster printed completely by itself before the machine moved to the next one. 
• But that’s not the full story. This test did not actually replicate the conditions I initially observed with the text and hatches. 

Experiment 2:

• So I repeated the process with color 1 and 2, separating the poster regions into sublayers 1-20
• This time something interesting happened.
  • The plotter printed the single line font and text outlines, staying within the layer regions similar to the first test.
  • Then the plotter moved on, printing each additional poster, staying within the region, but not printing the hatches.
  • Finishing the operation, the plotter returned and printed to hatches, again staying within the bounds of each layer. 
  • While this was not the intended effect, it was way faster and still saved a lot of time. 

Plotter completing one poster at a time

Round 2 Questions:

• After consulting the wonderful Ryan McKibbin, there were more questions. 
  • How is it sorting the order of the layers, by number? Alphabetically? By layer structure within the Rhino interface? 
  • Do layers vs sublayers vs sub-sublayers affect the order? 
  • Does the geometry in each poster sort the same?
  • Does it sort the same each time you send the file?

Experiment 3:

• Again, I was in the middle of production and did not want to alter my file too much, but some of these could be easily observed or altered. 
• By watching the machine, I could see that each poster was sorted differently than the next, but each time the file was sent, they were sorted in the same way. 
• The layers seemed to print in reverse order to their screen display, which was also reverse numerical order. To isolate the variable, I switched layer 10 with 11 and 18 with 19. 
  • The posters printed in reverse order to their screen display despite the layer names, that is 18. 19, 17. …12, 10, 11.

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  Full T and no A in Gateway, 2 in the bottom left

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  Notice the begging of the A but no T in gateway

Proof that the sort is inconsistent between posters

Analysis:

• From Experiment 1, the layer theory seemed promising. My operation time was cut in half, the machine wasn’t wasting time traveling all over the picture plane, the results seemed fantastic. 
• Experiment 2 showed me that there is something to the layer theory, but there is a greater hierarchy above the layer sort.
• Experiment 3 clarified the layer print order, and showed that the machine remains mysterious. 

Conclusion:

• Being able to sort by layer, despite its quirks, is a huge advancement in time savings. 
• Similar to the show/hide strategy, users can group their geometry by region so save travel time. The advantage of the layers is being able to send the whole file at once. 
• Additionally, there is a potential for an improved grasshopper algorithm to sort the geometry, and output to a myriad of layers, each guaranteed to print separately, in a defined order. 

Get Physical, TC2 Workshop

In this week’s workshop, we got to weave our drafts from ADAcad with help from Laura Devendorf, the software’s creator.

On the left is a 2 pic fabric, woven in black and blue on the front, and black and white on the back. This cloth was also woven with a ‘pic’ of conductive thread next to each weft, creating the potential to turn this test sample into a sensor in next week’s arduino workshop.

In the center is a another draft structure, a single cloth woven without conductive thread. My design in this test was much more structurally sound than the double cloth.

On the right is my knitting intertwined with conductive thread making another sensor. By stretching and compressing the sample, I was able to measure a consistent change in the resistance with a multimeter. This should turn into a fine sensor.

In the pictures below you can see the cloth being made, with all our samples ganged up in a row. Then you see Ryan Hoover cutting them apart to distribute to the class.

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AdaCad Workshop +Homework

Laura Devendorf’s AdaCad workshop was a lot of fun, and a great experience to meet an artist building their own software to enhance their craft. While her tool is still in development, and admittedly a bit confusing to use, for the unimitated, I saw how powerful it can be. The Grasshopper-like interface is especially useful, as you can make adjustments and they will carry through to the rest of your work. I also enjoyed the range of tools and customization that could be achieved. For example, in my first 3×3 square, I used an existing structure, the basket weave, than filled in the blocky areas with twills, ribs, tabby, and a randomly generated fill. From there I was able to further transform the pattern through shifts, slopes, and interlacements. Contrasting that method, for my second square I drew my pattern by hand then transformed it into a 2 pic weave. All in, I had a hard time getting started with the software, but I think I figured it out, and I think it’s a really great project.

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  Weave Pattern 1: Transformed Basket

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  Weave Pattern 2: 2 pic

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  Weave Pattern 2: Hand drawn structure

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  Weave Pattern 1 Beginning Basket

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  Weave Pattern 1: Transformations

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  Weave Pattern 1: Tiled Together

Research Project Ideas

Ever since freshman year, I have been enthralled with art making machines. Especially the three axis precision machines we call CNCs such as 3d printers, laser cutters, routers, and plasma cutters. These devises are capable of incredible additive and subtractive manufacturing, executed with precision, on a repeatable basis. These qualities are attractive, but I’m also curious to explore how these precise machines can be combined with messy, imprecise processes to create something partially left to chance.

A few Inspirations.
• The reprap and 3d printing communities at large. Many professionals and hobbyists alike have created and modified printers and accessories to enhance these machines.
• This Guy who added a sharpie to his plasma cutter. This modification improved his fabrication skills and times
• The MPCNC (Mostly Printed CNC). I really like this project. While it’s probably not the most rigid cnc for router milling (and there are some serious safety concerns from reading the forums) This project’s ingenuity amazes me and creates opportunities for super interesting modifications like one user who turned theirs into an embroidery machine.

• The Pancake Bot, I saw at the DESIGNS FOR DIFFERENT FUTURES show with my Art and Algorithms class. This opened my eyes to uses of 3d printers outside of rigid materials, and the sense that these machines can be used in humorous and frivolous ways.

While the machines on campus are fantastic at creating repeatable forms in a limited number of materials, a question arises from their uniformity. Could I build an xyz based machine to deposit other materials or processes? The answer is most certainly yes. Besides the pancake bot, there are already machines to 3d print wax, metal, clay, concrete, and more. So, I began thinking of other possibilities:
• Silly string
• Liquids
• Jell-O
• Paint
• Liquid metal
• Propane torch, for wood burning?

• Wood Burning tool
• Spray Foam

The two ideas most interesting and plausible in my opinion would be a wood burning tool for a simple conversion, and a spray foam dispenser for a more complicated build. The spray foam ventures further into my ideal realm of precision dispensing mixed with an unpredictable material, creating a form left partially up to chance. However, connecting a wood burner up to an old 3d printer sounds like a better place to start. The parameters and controls would be easier, and through grasshopper, I can sample images, than map the brightness value to time values for burning pixels into the wood. I’m not married to this idea, but I like it as a jumping off point.

Grasshopper Weaving

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Rhino Screenshots of simulated weaving

This workshop followed our lesson on traditional weaving, and the demo on the floor loom. Having seen that demo on the traditional loom, the risers and sinkers in grasshopper made a lot of sense in visualizing the simulated cloth. In this exercise, we created digital cloth through a progression of grasshopper components which created a series of evenly spaced pipes as the warp and a set of perpendicular pipes in the opposite direction which oscillated over and under the warp according to a set pattern. With this set-up we were able to recreate several traditional weave structures such as plain weave, twill, basket, diamond, reverse twill, etc.

While this was an interesting demonstration of the technology available to us, I think there is a lot more room to explore this process further. In the reading, the authors weaved on complex surfaces in grasshopper. I think that’s a place to start, but from there could you take that data and weave a structure which naturally conformed to the modeled surface after coming off the loom? How could this be used to reduce waste in the fashion industry?

Modulated twill

Weaving Workshop Reactions

I thoroughly enjoyed weaving on the 8-heddle floor loom. The main stitch I chose to experiment with was twill. While I’m positive that I am not using proper weaving terminology, I decided to modulate the variables of my twill, adding risers from two all the way up through seven, as well as adding additional lines of weft in each shed. Each change was made along with a direction change, creating a reverse twill whose pattern and appearance changes at each turn. While I began with a traditional twill of 2 risers, and 1 weft, I ended with 7 risers and 8 wefts in each shed. Compared to a lap loam, I loved the versatility and expanded possibilities provided by this loom. 10/10 would weave again.

Reading Response – Generative Algorithms Concepts and Experiments: Weaving by Zubin Khabazi and On Weaving: The Fundamental Constructions by Annie Albers

Zubin Khabazi’s guild to visualizing and encoding weaving to use on a Jacquard Loom is both thorough and fascinating. The step by step breakdown of the process makes it understandable, something which can be hard to achieve when looking at the whole grasshopper definition at once. I appreciated the attention to detail and the explanations of the logic regarding each step. This reading paired wonderfully with Annie Albers’ chapter on the fundamentals of weaving, and her explanations of how different weave patters create cloth with different purposes. I haven’t worked with a lot of fibers materials in my practice, but pattern and repetition are often part of my process, so I’m excited for this workshop and demonstration.

Encoding Environment Workshop

Marantha Dawkins’s workshop on pattern building in grasshopper was a great example of how versatile parametric design can be. The workshop involved sampling brightness values from an image, then mapping those values to constructed pattern pieces in grasshopper, recreating the image though abstract shape. From there the patterns were traced in hot glue on a stretched piece of fabric generating contrast between the rigidity of the glue and the pliability of the fabric under tension. Seeing each group’s project branch off in different directions depending on the density and geometry of the patterns they chose was a really fantastic experience.

My group made the pattern from four inputs: a star, a series of dashed lines, a dense squiggle, and a blank. After printing the pattern and applying the glue, the stretched fabric was released from tension and allowed to settle into its new shape. We learned that areas left blank contracted and remained relatively flat, while areas with more glue rippled the fabric into an undulating landscape. In areas with several squiggles, peaks and valleys were formed, running up and down along the grid structure. In contrast, areas with several stars created round bulges expanding upwards. Once finished with the formal workshop, we used the lessons from the patterns to create a freehand composition with experiments such as folding the fabric, using the glue as a coloring template, and applying the glue in new ways. This resulted in a composition of free flowing, almost geographical ridges, and a spine-like figure on one side.

This project was interesting, and surprisingly fun trace the pattern with the glue. Although I probably won’t be adding hot glue drawings to my studio practice, the pattern generation from an image is definitely an idea worth exploring further.

Reading Response – The Sympathy of Things by Lars Spuybroek

In Lars Spuybroek’s 2011 book The Sympathy of Things I agree with the idea in the first section that “as all craft moves toward design, all labor must move towards robotics”. I have been using digital design for a few years, and I often feel as though I am missing the craft nature of artwork. While I frequently ponder this question of craft and human input while working with machines, I’ve struggled to articulate how craft plays a role in CNC fabricated art. I appreciate how Spuybroek has reframed craft in this book and recognized that today’s CNC machines can fabricate complicated interconnections and unique parts, unlike the factory machines and molds criticized for having only one mode of operation: mass replication. This ability to create unique parts, changing the operation of the tool each time, allows for greater creativity and craft in the design phase, and as Spuybroek states, these new digital relationships create a dynamic merging of the carving and modeling ideas at the same time. While I agree with many of the claims in this excerpt, I do think the tangents on handwriting, butchers, and more seem unnecessarily long and drawn out.