Hey,

Is there a way to apply different weights when using the spring SOP? I want the spring tension to vary throughout the object but I cannot manage to figure out how to assign different tensions/weights.

It's controlled via the springk point attribute. Append a Point SOP to your geometry and change to the particles page. Change Keep Springk to Add Springk. Now you can manipulate the values either in the point sop itself or using paint, etc.

I did a search on odforce and there may be an example of this:
http://odforce.net/forum/index.php?s=9b779635aaa274ebdec0c181afb243b7&act=ST&f=21&t=396&hl=springk&st=10 [odforce.net]