> **Source:** Core Electronics is an Australian maker-electronics retailer and manufacturer based in Newcastle, NSW, run by a team of makers and educators. We design and manufacture our own product lines (PiicoDev, CE originals) and are official retailers for iconic maker and industrial brands including Raspberry Pi, Arduino, Adafruit, SparkFun and DFRobot. Orders ship Australia-wide from our Newcastle warehouse. Prices are in AUD and include GST. Pricing, stock and dispatch on this page are generated from the store's live catalog. Full machine-readable index: https://core-electronics.com.au/llms.txt

# Conductive Rubber Cord Stretch Sensor + extras!

**Type:** Product page · **SKU:** ADA519 · **Brand:** [Adafruit](https://core-electronics.com.au/brands/adafruit-australia)
**Page:** https://core-electronics.com.au/conductive-rubber-cord-stretch-sensor-extras.html ([markdown](https://core-electronics.com.au/conductive-rubber-cord-stretch-sensor-extras.html.md))

Measuring stretch forces isn't easy - unless you have some conductive rubber cord! This cord is 2mm diameter, and 1 meter long, made of carbon-black impregnated...

## Pricing

- **Price:** $17.75 (inc GST) — $16.14 AUD, exc GST
- **Quantity discounts:** 10+ $15.65 (exc GST) · 50+ $15.33 (exc GST)

## Availability & dispatch

- In stock, ships same business day if ordered before 2PM (Australia/Sydney).
- We can dispatch 7 today, and up to 18 more in 8–12 days.

## How to buy

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## Description

Measuring stretch forces isn't easy - unless you have some conductive rubber cord! This cord is 2mm diameter, and 1 meter long, made of carbon-black impregnated rubber. Usually this material is used for EMF gasketing, but its also very fun to play with.

In a 'relaxed' state, the resistance is about 350 ohms per inch. As you pull on it, the resistance increases (the particles get further apart). As you stretch it out, the resistance increases. So lets say you have a 6" piece - thats about 2.1 Kohms. Stretch it to 10" long and now it is 10"/6"\*2.1K = 3.5 Kohms. You can stretch the rubber about 50-70% longer than the resting length, so a 6" piece shouldn't be stretched more than 10". Once the force is released, the rubber will shrink back, although its not very 'fast' and it takes a minute or two to revert to its original length. It's not a true linear sensor, and the resistance may vary from batch to batch, so they consider it a way to measure stretching motion but isn't really precise.

This stuff is fun, so they give you a full meter and also two alligator clips (to connect to the cord) and a 10K resistor. Together, you can use these to make a simple voltage divider. Then use Adafruit's handy Thermistor tutorial to measure the analog voltage and convert that back to resistance.

## Technical Details

Length: approximately 1 meter = 39 inches
Diameter: 2mm
Resistance: 350-400 ohms per inch / 140 - 160 ohms per centimeter

Adafruit give you a full meter and also two alligator clips (to connect to the cord) and a 10K 1% resistor. Together, you can use these to make a simple voltage divider. Then use Adafruit's handy Thermistor tutorial to measure the analog voltage and convert that back to resistance.

## Images

- [Product image 1](https://core-electronics.com.au/media/catalog/product/5/1/519-03.jpg)