What is the best way to size an extension spring with specific requirements?

[Avis]

I'm in need of an extension spring with some specific requirments:

Material: Stainless Steel
Diameter 0.75inch
Rest Length: 5 1/2inch inside the hooks
At 7 inches a forcle of 10lbs
At 10 inches (full extension) a force of no more than 20lbs (As low as possible)

Any idea on how to size this spring? What diamter wire will it need to be etc.

 

[ginarose12]

Hey Avis...I think you would be able to find what you're looking for at this website. They have a huge range of extension springs, and I've had success before. All the best!

http://stanleyspring.com/

 

[Mech_Engineer]

Take a look at Century Spring's online spring calculator: http://www.centuryspring.com/Store/search_extension.php

 

[Avis]

Hey, thanks guys! I found an off the shelf spring that is almost perfect! Can't complain with that!

 

[ginarose12]

You might find luck at this site...

http://stanleyspring.com/

I know they have a lot of different springs. I'm not too sure if they have the type you're looking for, but I'm betting they do. Good luck, Avis!