I was trying to measure the mass of a container using a potentiomer with spring under the container but this approach seems mechanically difficult so any ideas of how I can measure the mass of a container without spending much? potentiometer method was cheap since POTS arent expensive but those pressure sensor pads are not as cost effective..any ideas on even how I can use a POT to achieve this? Currently below is how I had it working..
If you put the pot. at the pivot you will get more rotation.
twirap:
this approach seems mechanically difficult
Difficult in what way?
difficult that spring calibration is required and over time the spring will wear out in weeks...
twirap:
difficult that spring calibration is required and over time the spring will wear out in weeks...
If it's wearing out, either you're using the wrong material or you're taking the spring past its elastic limit. How many weighing cycles is this device intended to last for?
difficult that spring calibration is required and over time the spring will wear out in weeks...
As far as I know, all balances & scales have to be calibrated periodically if they are used for anything critical. ...Unless you've got a regular old-fashion mechanical balance with counter-weights.
I've got a 20-year old vehicle and the springs have never worn out. 
A pot should be rated for at least 10,000 cycles.
roughly 21000...nothing critical...i think DV's thought helps quite a lot! Maybe I will go for a more durable spring..