twist sensitive resistor?

Wind a string around the object and connect the end to a strain gauge.

Yup, sure thing!! It's called a strain gage. Omega, among others, make them. Get some info about them at

Dave M

Never take a laxative and a sleeping pill at the same time!!

Use a Analog Meter Movement, and monitor the current required to re-center the needle. I have seen this setup used to measure sub milligram quantities

Yukio YANO

Jameco sells a resistive flex device that has a range of around 10K-40K. It's a long link, but here it is!

"Yukio YANO" wrote

needle. I have seen this setup used to measure

When I was doing postgrad physics, I used a "microbalance" that used a very similar principle. It routinely measured _microgram_ changes in mass of a gas-adsorbing sample as it was exposed to varying pressures of the gas to be adsorbed.

It is a very good method for measure miniscule mass (well, weight) changes.

May not be what the O.P. is looking for though, but I thought I'd post to recommend this method for ultra-sensitive weight-change measurements.

Martin