Printable spring for wade's extruder

Some people get away without using springs on wade's geared extruder (http://www.thingiverse.com/thing:1794), but I felt that this was too sensitive to being over/under tightened. I wasn't able to find appropriately sized springs at the local hardware store either.

I did cut some longer springs down to size, but I also made these. At least in the short term, they seem to work about as well as actual springs. The biggest difference is that they don't have as much travel. In my opinion, that ac