7. Textile as Scaffold#
What I Made#
A Little Background#
In the early hours of a sunny Colorado morning in 2016, a group of palaeontologists, among whom a renowned scientist colloquially called Jurassic Bob, dug up the fossil of what looked like an animal scale. The palaeontologists had no idea where the scale came from and to what animal it had once belonged. It must have been a very large creature, considering the size of the scale, which was as big as the hand of a young teenager. When they tried to date the scale to establish its age, they found to their surprise that they couldn’t. They tried all available dating technology, such as carbon dating and radiometric dating and even some beta-versions of state of the art nanotechnology. In late march 2018 Jurassic Bob received a call from the team of specialist scientists who were working out how to date the scale. ‘Bob’, they said, ‘Sit down. We think we have solved the problem, but you are not going to believe this.’ Bob sat down and took a sip of his coffee. He figured he had heard his share of unbelievable facts and could probably do with one more. ‘Bob,’ the dating professor told him, ‘we believe the scale has to be dated from no other period but the future. We think it originates some million years from now. We have tried to distract some DNA samples from the fossil. From what we can tell of these little DNA fragments, we believe that we might conclude that this animal is most likely some kind of canine. A breed of dog that is yet to come into existence.’
Making a Mold#
First I sketched a scale with pencil. Then I sketched the same in Illustrator. I opened Meshmixer and started sculpting on a default object (sphere) until I had the shape I wanted. I found some nice features to tweak the shape, but it still needs a lot of practice before I can really make a detailed shape (for instance of a dog with scales from the future). In Meshmixer I placed the scale-shape on a square so that I had a more firm underground for the mold. I exported the file as .stl and used this to mill the scale mold with the milling machine. For this I used a piece of insolation foam.
To learn Rhino I find this very nice introductionary video tutorial with Mary Fugler.
Making a Composite#
I wrapped the mold in ordinary kitchen foil because the foam would probably loose its shape when it got wet. I had no sealer or coating, else I could have used this instead. Also I had no vacuum bag or vacuum table to use. So the composite had to dry overnight on the mold, unless I used a blow-dryer. I greased the foil with vaseline. I cooked up a batch of bio resin and tried carefully to brush layers on several layers of fabric. Turned out the mold was too small to take roughly cutout pieces of fabric. Also I used synthetic materials that melted when I wanted to blow-dry them. (Resulting in some rather interesting failures.) When I lasercut some cotton fabrics to exactly fit over the mold, it was easier to make composites. I tried different glues (white glue and natural dextrin-based glue) and different variations, like having one, two or three layers, drying them on the mold and drying them flattened under a very thick and heavy book. I made a composite by melting thin sheets of synthetic plastic between fabrics with a hot iron – this composite is firm and holds its shape, but it is also still flexible. I even tried quilting. For this I used a super thick filling. This quilted ‘scale’ also became very firm, so I suppose I could use this as a ‘building block’ or ‘scaffold’ for something steady. Very good documentation on how to make composites was made by previous Fabricademy-participants.
Some pretty failures.
Lasercutter to the rescue.
Further investigations. Iteration with quilting, using a very thick layer of filling (above), iterations with one, two and three layers using natural glue (below).
References and Inspiration#
Listen to this beautiful podcast on ‘Jurassic Art’.
Making a Crystal#
A crystal can be made at home. In 2014 the Royal Society of Chemistry even held ‘a global experiment’ for growing crystals at home. Crystallization is a method of solidifying fabric and giving it a beautiful look. For this you must make a fully saturated solution of sugar, salt, alum, Epsom salt (bitterzout) or any other crystalized substance you would like to use. To fully saturate the water it is best to boil it and stir until the crystals no longer dissolve. Pour the solution in a pot and hang a fabric in it (or a piece of yarn). Make sure the fabric or yarn does not touch the bottom or the side. Leave to ripe. Within an hour or after a few weeks you will have beautiful crystals! You can even grow crystals on e-textiles.
Above left: coton pompon to be dipped in saturated alum solution. Below left: the same now covered in alum crystals coloured with red food dye. Right: crystals from the materials archive in the TextileLab.
An unexpected beauty: I dipped a knitted fabric in some epsomsalt solution with green food dye, left in a petridish to dry. There were no crystals on top but there were some on the bottom. Almost like the fabric is frozen solid.
Step by Step Manual for the Milling Machine @ Waag#
As explained by Henk and Wendy and noted down by me, Teresa (disclaimer: maybe with some misunderstandings, so always ask for assistence from a pro)
Settings and points of interest are shown in this slideshow.
The Machine#
- The ShopBot PRS standard is a 3-axis milling machine ideal for making big things. From furniture to large scale models to large carvings and many more applications.
- A ShopBot is an amazing do-all tool for precisely cutting, carving, drilling or machining all kinds of things from all kinds of materials. A ShopBot is like a large plotter that moves pens around the surface (in X and Y axes) to create a drawing. Only a ShopBot moves a cutter around a big table (X and Y axes) and moves it up and down as well (Z axis) allowing it to make 3D movements and cut all sorts of shapes.
- Specifications
- Working area: 2440 x 1220mm | 96” x 48”
- Maximum Part Size: 2440 x 1220 x 150mm
- Software used: Partworks 2D & 3D
- Acceptable file formats: DXF, STL
- Mechanical Resolution: 0.015mm | 0.0006”
- Position Accuracy: +- 0.127mm | 0.005”
- You can cut and carve: wood, plastic, styrofoam and many more
- You can not cut: metal
WARNINGS#
- Hands never on the milling machine when it is running
- All hair and facial hair must be tightly tucked in
- No iron (screws, nails, metal scraps) on the bed/table
- Preferably work with two people together
- Stay with the milling machine at all times and observe the milling: you are the emergency stop (spacebar)
- Be aware of fire in the hose – fire in the dust collector bag could burn down the FabLab
- Book the machine for at least a day: milling takes a LOT of time (setting up takes about an hour, the actual milling might take up from a few hours to a few days, depending on the material you use)
The Software#
- Put USB in the machine
- Save .stl file on the desktop
- Choose the program Partworks (if you want to mill a 2D object) or Partworks 3D (if you want to mill a 2,5D object) Find a more in-depth manual here.
- Load file in Partworks
- Now there are 7 steps to work the file (this will take approximately an hour)
- Step 1: top surface > model size (adjust or not) > APPLY > next
- Step 2: Material size + margins > put in the exact measurements of the material you are using for the milling (we use polystyrene foam) > software shows preview > adjust > ENTER
- Set Z zero by setting it to the material > APPLY >next
- Step 3: set the roughing tool path. This will roughly cut out the shape
- We use a 5 mm mill end (the ‘drill’ that does the milling) > SELECT > pop-up window
- Put in the parameters for pass depth (how deep), stepover (overlap), speed (spindle per minute), feed (speed of movement on x y z axis), plunge (depth downwards)
- We set our perimeters to pass 5 mm, stepover 1,5 50%, spindle 18000, feed 120, plunge 25
- Go to tool path parameters: rapid clearance path 1 mm, machine allowance 0,5 mm (here you could tweak a negative+positive model to leave a few mm gab for the fabric you want to mold by setting a an extra +mm or –mm)
- Choose the milling strategy > top to down, Y from X, etc., we choose 3-D raster > calculate
- Try different strategies to see if the milling goes faster > APPLY > next
- Step 4: set the finishing tool path > choose 5 mm end mill
- We use the same settings as the rough tool path, but lower the feed to 100 and increase the stepover/overlap to 0,6 to get a neater result > calculate > try different strategies to speed up the milling > APPLY > next
- Step 5: cut out tool path, either a silhouette or pulp > next
- Step 6: preview milling > reset former steps if needed
- Step 7: save G-code to shopbot (.sbp) > use one file when settings for rough and finishing tool path are (more or less) equal, otherwise save as two different files, one for roughing and one for finishing
- Save changes > yes > save
The Hardware#
- Work step by step and double-check
- Put double-sided sticky tape on the bottom of the polystyrene foam in different directions, so that it covers the entire bottom, and stick it firmly on the milling bed > some materials need an extra wooden bed that you can screw on the milling bed with ‘woodies’ (special screws)
- Better use an end mill (flat) and not a ball mill
- Start the machine with the red switch on the side (you cannot upload the software otherwise)
- Open Shopbot on the computer Find a more in-depth manual here.
- The green dots indicate the end stop of the machine
- Command K in yellow box – now you can control the nosel to move for calibration
- Put a 5 mm end mill in the nosel > pull down the plastic cap with wing knot > use tools to remove the nosel collar > remove the spin wheel and put in the right size end mill with the right size spin wheel > push them back into the collar > use tools to firmly attach the collar back to the nosel
- Now set the ‘origin’ on the computer
- Press K in yellow square > move nosel to zero point (you set this earlier in step 3 in the software-setup) > now ‘zero’ the x and y axis by selecting the ‘zero’ menu on the top, hit the option “zero [2] X&Y”
- ‘Zero’ z axis by using a metal plate > put it under the nosel > check if the green dot lights up in the screen (this means the nosel ‘reads’ the metal plate > THIS IS IMPORTANT otherwise the nosel would keep going down > push the zero Z icon > hit enter when you hear a sound > push ok > 3.070 is the height of the metal plate > push K in yellow square > move nosel up and remove the metal plate
- Take a snapshot of the settings in the red zero-window so you can remember them
- Point the lamp on the nosel to the material (almost set…)
- Open your file in the Shopbot software
- Put on the machine with the small button in the front
- Put on the dust collector bag with the red button in the corner of the room – green light goes on
- Turn the key under the red switch on the side of the milling machine (the one you used to start up the machine)
- Match the speed in the little box under the ‘on’-button to the speed you set in the software (120 in our case)
- Put on ears and eyes protection
- Press start > double-check if all is ok and if you have done all the steps > press ok
- Stay with the machine when milling and don’t do anything else
- When done, first turn off the software, then turn off the machine
- Turn off everything and carefully take the model off the milling bed
- Clean up before you leave
Note to self#
- Nobody knows what dinosaurs actually looked like. Scientists tend to be quite conservative when reconstructing them since they do not want to give an image of something they cannot prove. But this strategy seems insufficient because most dinosaur-renderings turn out as if the animals are shrink-wrapped. Some paleo-artists have therefore started to experiment with giving dinosaurs more body fat, feathers and furs. Watch this great lecture on the history of dinosaur reconstruction and this lecture on contemporary speculative dinosaur reconstruction. In museums dinosaurs are usually displayed as skeletons, painted illustrations or sometimes as really ugly plastic automata. Wouldn’t it be a supercool idea to work with fabrics+composites to design actual skins for dinosaur skeletons? To drape these ‘skins’ over the skeletons like tent fabric and harden them? This would give so much opportunity for speculation and experiment. It would be like designing a costume for a dinosaur.
- Would it be an idea to make a ‘tent-quilt’, meaning some sort of hybrid between a blanket (sleeping bag) and a tent with light-weight scaffold? The tent-quilt might be maximally 20-40 cm high, enough to fit a sleeping person on her side. It might be a solution for regulation temperature and humidity because the height of the top could be changed? In hospitals sometimes ‘blanket bars’ are used to lift blankets off specific (injured or sensitive) parts of the body.
- A small mold with positive and negative could be used to create interesting textures.
- For press-weight it is possible to use a bag of sand, rice or even water.
- Link for laser kerf patterns
- Link for laser kerf patterns including laser kerf pattern generator
Image: John Conway.