Swatch Making

in progress

intro

Making swatches for e-textiles.

The goal is to provide examples for simple and more advanced circuits on fabric.

The possibilities to make "soft" versions of electronic components like switches and battery holders.

preperation

Table with tools

Putting a special spool with conductive thread inside the sewing machine.

Lock Machine

Table with swatches

tools

Machines

Sewing machine
lock machine
soldering station

scissors
needles
stitch undo tool

electronics

leds
coin cell batteries

led conductive thread connection

Connecting the legs of the LED to the thread is always a bit of a problem.

There is a method making an eyelet of the leg of the LED and knotting the thread.

I trepide out a new way for me, with a small clamp:

materials

non conductive materials
conductive materials

vlisofix plus aluminium foil

conductive threads

There are many different conductive threads. Some like the Karl Grimm silver thread can be soldered. Most others, which have a plastic kernel cannot be soldered.

For using conductive thread in my Janome sewing machine I have to change the bobbin holder. I then can put the stainless steel conductive thread in the spool.

All conductive threads have different properties. The most important property for the use in a circuit is the resistance. The resistance of a conductive thread can vary from very little (say less then 1 Ohm every 10 centimeters) to very high resistance, sometimes even kOhm or mOhm.

One of the swatches shows 6 different conductive threads.

On school we only have the stainless steel, which consists of steel fibers around plastic fibers. When you wash this thread it gets corroded, and will break down.

Many conductive threads can only be bought industrially and are not available for small consumers.

It is interesting to look at the conductive thread under the USB microscope, then you get a better understanding of the structure of the materials and you can understand why some of these threads break down easily.


conductive thread 1: Stainless Steel, 4 ply, the school material.	conductive thread 2: Karl Grimm, can be soldered, silver, head to get, the least resistance	conductive thread 3: Elinox, high resistance.	conductive thread 4: Pes Det, the winding of the conductive metal is very conspicuous	conductive thread 5: Wool + steel, lots of wool and the single steel fibers, in this sample most of the resistance	conductive thread 6: Bekinox, feels very heavy
resistance: 5.0 Ohm per 10 centimeters of the sample	resistance: 0.5 Ohm per 10 centimeters of the sample	resistance: 90 Ohm per 10 centimeters of the sample	resistance: 18 Ohm per 10 centimeters of the sample	resistance: 420 Ohm per 10 centimeters of the sample	resistance: 1.0 Ohm per 10 centimeters of the sample

ideas

fabric battery holder
making a circuit
connecting a LED
making a textile switch

Fails

From errors you learn the most. I thought I would get a better connection by making the stitch length smaller. But then the stitching on the heavy material gets irregular.

That induced me making a swatch of the different stitch length. It turned out that the default stitch length of the machine 2.4 mm was the best. I also tried out some decorative stitches, and the zig zags.

fabric battery holder

The last battery holder I made functioned, but is was also a bit inconvenient, because it was cumbersome to get the coin cell out. It was too stiff and has only one entrance.

Therefore I designed another way, a battery holder with two sides open. The base fabric holds a pattern of conductive thread and is for the larger + side of the battery. The fabric on top has a nudge of conductive material that pushes on the - side of the battery. There is of course a loop going on the outside to the minus, preventing a short cut.

nudge on top of the fabric made with a zig zag three times on top of it.

With a needle the wire has to be pushed through the material, otherwise there will be a short cut.

Placing the upper side of the fabric battery holder.

The piece is sewn on the base fabric using a zig zag, so that we don't have to fold the side again.

Connecting the wire to the wire of the circuit.

Intermediate stages

Because the sewing machine has a special spool cylinder for the conductive thread installed, the fabric battery holders have to be made later.

Simple circuit, with one LED. The corner fold is the switch.

Circuit with two LED's in parallel.

results

The first swatch is trying out the conductive thread, as can be seen, in plain stitching, when the stitch length is too small, the stitch gets irregular at this fabric.