10. TEXTILE SCAFFOLD¶

INSPIRATION¶

Wooden Textiles - Elisa Strozyk - applies lasercut shapes on fabrics
Ballett Back - Alice Potts -growing crystals on sweat
Be grounded - Lara Campos - growing grass on textiles
Textile Farming - Svenja Keune - growing seed on textiles
BioKnit - Romy Kaiser, Ahmet Topcu - filling knitted fabric with mycelium

MAKING A MOLD - RHINO¶

To create a mold for the CNC milling, we worked with Rhino. Alessia and I worked as a group and decided to create a wave-like shape. We came across an artwork by Robert Fathauer, which served as the starting point for our design.

Criteria for CNC mold design

For preparing a mold we had certain criteria to keep in mind:

Avoid negative angles
Maintain a minimum distance of 5 mm between objects so the milling bit can pass through
Maximum depth should be 3 cm; otherwise, the upper part of the milling bit may get stuck on the foam and scratch it

Design

As material for the mold we used foam with a thickness of 5cm.

Grasshopper

We worked with the differential growth function in Rhino. We used the outline of the design above and let differential growth develop inside this shape.

We used Aslis Grasshopper file from Computational Couture week to apply the differential growth function.
We drew the outline of our shape and used this outline as the boundary for the differential growth.
Then, we created an attractor curve to influence the growth, so the expansion would occur inside our shape and depend on the shape of the attractor curve.
We had to experiment a lot with the attractor curve to create nice inner lines that maintained enough distance between each other to fit the milling bit and avoid crossing lines. We found that crossing lines could be eliminated by moving the growth slider very slowly, allowing the computer to calculate without problems, resulting in no crossings.
After having found a nice shape we baked the shape to work on it in rhino.

Rhino

In Rhino we measured the distance between the lines to make sure that also if we create a pipe around it there will be at least 5mm for the milling bit to go through.
Then we used the Pipe command to create a pipe around our inner lines with a diameter of 0,7 cm

Final mold¹

Brain-mold-foam/week10 by johanna.schrue on Sketchfab

CNC MILLING¶

This is the CNC Milling machine at Waag we worked with this week.

Spindle Instructions

The milling bit is connected to the spindle.
The collet serves as the holder for the milling bit—ensure the bit is tightened securely.
Insert the milling bit at least one centimeter deep into the collet to ensure it is properly fixed.
The machine key is attached to the tool and is required to tighten or loosen the milling bit. The spindle cannot operate while the key is inserted in the machine.
Always stop the machine before working on the spindle.
In case the machine is stopped, ensure the spindle also comes to a complete stop immediately. Allowing it to keep spinning may cause overheating or even fire.

General Safety¶

There is a safety exit door in the room
The emergency button stops the machine, but the spindle may still rotate for 30 seconds.
Do not operate the machine when stressed or tired.
Remove jewelry, tie back hair, and do not wear loose clothes.
Check the surroundings of the machine to ensure all axes can move freely.
Keep the machine surface free of dust and debris - clean before using.
Fix wood firmly with screws (plan screw positioning carefully). Be aware that if the milling bit hits a screw, metal chips are drawn into the dust extraction system, which combined with wood dust and fresh air can create conditions conducive to fire.
Never leave the machine unattended; stay close to stop it immediately if needed.
Be able to listen carefully to the machine for any irregular sounds.

VCarve Pro Workflow¶

Import STL files into VCarve Pro - Import to Fabri-cnc → 2025 file and put file on the computer
Open a new project
Job setup:
- Input material dimensions in millimeters, ensuring the material thickness checkbox is set.
- Material Z has to be set on top of the material - thickness: 50mm
- Define XY datum position this is the job origin.

Rough machining Toolpath

for rough shape.
Use a 5mm milling bit with 30mm stick-out for rough machining.
Use 90% step-over, meaning 10% overlap for efficient cutting.
Use slow spindle speed when machining foam.
Feed rate is set to 90, plunge rate controls how fast the bit advances into the material.
Use different milling bits for rough and precise machining.
Save the toolpath to a file spb. file for importing it into ShopBot

3D Finishing Toolpath

for detailed shape
Set the settings as in the pictures below
Save the toolpath to a file spb. file for importing it into ShopBot

Machine & Material preparation¶

Tape the foam securely with double-sided tape onto the sacrificial layer of the machine.
For wood: use screws to fix the wood (consider carefully where to place the screws in your design). Take care with screw placement—if the milling bit hits a screw, metal sparks may be drawn into the air exhaust, where there is wood dust and fresh air—a good condition for fire hazard.
Position the material straight and parallel to the X-axis, and place it close to the computer so you can properly monitor the process.
Check the surroundings of the machine—can all axes move freely?
Clean the surface thoroughly—there should be no dust.
Fix the milling bit and attach the dust skirt. Different milling bits are used depending on the project.

ShopBot¶

ShotBot is the software to control the cnc milling machine and where we upload the files created in VCarve Pro.

Calibrating

Open ShopBot Software - when opening ShopBot, an error message may appear—close it.
First, calibrate the position of the spindle because the machine does not know its location.
Y represents the width of the table, and X represents the length.
Turn on the machine using the switch on the side and the ventilation in the small room at the back of the room - before check all security guidelines mentioned above
Press shortcut “K” to open the interactive keypad in ShopBot; this allows you to move the bridge. - If the machine is off, you can move the bridge by hand, but never move it by hand while the machine is on, as this could damage the motor. Also, avoid placing your hands on the rail, as the machine will not stop if your hand is there.
Use the arrow keys to move the axes: left and right arrows control X, up and down arrows control Y, the upper buttons control Z
Move the spindle to the corner of the machine.
Click on “Calibrate.” The machine only has sensors at the ends of the axes, so it will stop only there to calibrate.
The red box in the image shows the spindle’s position. After calibration, the control panel on the right will display X and Y as zero.

Z-axis calibration

Set Job Origin

Set the job origin by moving the milling bit to the corner of the object (always the lower left corner). Take a photo to document the job origin - in case the job fails you need to know the location
Click on the X and Y axes. X and Y will show zero in the red box with the location on the right.
Set the Z level initially to the machine surface to avoid marking the machine. Then, set Z on top of the material by measuring its height.
Place the metal plate on the foam and bring the milling bit close to the metal. Briefly touch the drill tip to the plate to check that the circuit is closed (the indicator light will blink in ShopBot). This ensures the bit won’t cut through the metal during calibration but will stop automatically.
Z = 0 will be displayed in the red box.
Now, import the G-code and first start the rough toolpath and afterwards the finishing toolpath

CNC Milling¶

Before starting the roughing toolpath, you have to turn on the spindle by inserting the key into the lock and turning it around.
Set the speed control to the appropriate value—we worked with 80.
When starting the roughing toolpath, keep your hand on the pause button in case something goes wrong or if you have mixed up the axes.
After roughing, run the finishing toolpath, which takes longer. Always stay beside the machine during operation. In case something goes wrong - pause the job and turn of the spindel or stopp the machine with the red stop button and turn off the spindel.
After finishing the job, turn of the machine, take off the foam and clean the machine with the vakume cleaner.

MOLDING¶

Fabric Molding with Moldes¶

For molding fabrics and biomaterials, we used molds from previous years as well as new ones created with CNC milling.

Preapring a foam mold

Apply Vaseline to the mold surface.
Cover the mold with plastic foil; the Vaseline helps the foil stick and protects the foam underneath.

Agar Agar & Organza¶

Recipie

8 g Agar
24 g glycerin
400ml water
Mix in a pot and stirr. Then let it simmer for around 30 min at 80 degrees until it becomes syrup like consistency.

Alessia and I used the mold we created with the CNC milling machine for this test. After preparing the mold, we poured the agar mixture inside it. Then, we placed the fabric on top of the agar and cast another layer of agar over it.

Agar Agar & Hemp¶

For this test, I immersed the hemp in the agar-agar mixture and molded it over the shape. The result was very successful—the hemp maintained its shape well. After drying, the agar-agar became completely invisible, leaving only the molded hemp forms visible.

Agar Agar, Bamboo & Wool¶

Alginate & Bamboo fibers¶

Recipie - 12g alginate - 40g glycerin - 400ml water - 10% calcium chloride solution

For this object I used the same mold as before and cast a mixture of alginate, bamboo fibers, and paper tissues on it. The bamboo fibers were prepared by cooking with soda to make them softer. After applying the mixture to the mold, I sprayed it with calcium chloride to cure it.

Insted of tissue paper I used wool to stabelize the material.

Here I added some cochinille pigment to the alginate mixture for the pink color. Then I added some bamboo fibers and some shells.

Alginate & Organza¶

For this sample, I first applied a layer of alginate, then placed organza fabric on top, followed by another layer of alginate. I massaged the alginate mixture into the fabric to ensure good adhesion and texture. After that, I sprayed the surface with calcium chloride to initiate the curing process.

Alginate & Net¶

For the second sample, I dipped a net which was a left over from buying oranges into the alginate mixture and carefully wrapped it around a jar, cured it and allowing it to dry in place to take the jar's shape.

Fabric Molding by Simmering¶

Prepare the Fabric

Choose the fabric you want to mold (e.g., silk or denim).
For rounded shapes with silk, gather small marbles (murmeln).
For structured shapes with denim, gather screws.

Insert Objects

Place the marbles or screws inside the fabric piece, arranging them sequentially to create the desired shape.
Secure the objects in place by sewing around them with thread so they do not move during simmering.

Simmer the Fabric

Place the fabric with the sewn-in objects into simmering water.
Leave it to simmer for approximately 20 minutes to allow the fabric to mold around the objects.

Cooling and Drying

After simmering, let the fabric cool down while the objects remain inside.
Once completely dry, carefully remove the marbles or screws to reveal the molded shapes.

Crystallization¶

*Preapring saturised solution | Some of the grown crystals*

Recipie

1kg Water
700g alum
white vinegar - for cleaning the jars

To perform crystallization, start with 1 liter of water and 700 g of alum to create a saturated solution. Heat the water because warm water can dissolve more crystals than cold water. Then gradually add the crystals while stirring until no more crystals dissolve.
For crystal growth, place the material you want the crystals to form on inside a clean jar. The jar can be cleaned with some white vinegar beforehand. Ensure this material does not touch the bottom or the sides of the jar, as otherwise crystals will grow on the jar instead of the material.
Once saturated, filter the solution through a coffee filter into the jar with you material to grow on.

After several hours, you will start to see crystals forming.

Crystals & Hemp¶

I tried growing crystals on several different materials with various results. Growing crystals on hemp worked very well. I even made a small sculpture out of crocheted hemp and pipe cleaners. The crystals particularly liked the pipe cleaners and grew impressively on them.

*Crystals grown on hemp & pipe cleaners*

Crystals & Cattails¶

As a group we tried to grow crystals on the cattail fur we made in the biofabrication week. Some crystals were growing but the fur got really stiff by the alum.

Crystals & LED¶

I also grew crystals on an LED. The crystal grew very large but the LED still lit up perfectly.

Crystals & Thermochromic pigments¶

Next, I attempted to color the crystal solution using color-changing pigments and grow them on conductive steel wool. So the color would change when the electricity flows through the steel wool. Unfortunately, the pigments did not dissolve properly, so the crystals did not take on the black color as intended; instead, the pigment remained undissolved in the crystal. So in the end the result is some steel wool coated with crystals.

*Saturated solution with thermochromic pigment*

Crystalized Steel Wool

Crystals & Conductive Ink¶

I also tried adding conductive ink to color the solution to create conductive crystals. This experiment didn’t succeed either, likely because I didn’t use enough ink.

FILES¶

brain mold - stl.file ↩