Finding Small Machined Springs for Probes

[_Bd_]

Hi,
I usually buy off-the-shelf springs, however I am working on a design that requires some very specific features on each side of the spring (if possible), however this is a very small device, (its a probe).

Anyways, I was thinking of getting a machined screw, as I've seen some very good looking ones and very complex features on the ends. I was hesitant however, I wanted to know if anyone has had experience with Polycarbonate (stock from McMaster) or even delrin.
Do you think its possible to machine out PC or delrin into a spring with an OD of aprox, .180" ?

I mean, I don't doubt the machine's capabilities to do it, I am more curious about its performance as a springing material. . . Has anyone had experience with this?
What material properties should I be looking for when deciding a spring material? as far as I know PC is very ductile and should not pose a problem, however I am worried about its ability to go past its yield strength (even tho I am using it mostly as a compression spring)

Any advice is greatly appreciated. Thank you!

 

[Q_Goest]

Try doing a search for plastic springs. They're available off the shelf.
http://www.leespring.com/int_learn_LeeP.asp
Alternatively, if you don't need solid plastic, you might consider having steel springs coated with rubber or plastic.