I doubled the length (and the number of coils) of the Springamathing 1.0 (http://www.thingiverse.com/thing:12053).
Now you can print it scaled down by about 50 percent to get a smaller and more flexible version of the original spring.
At the picture you can see the long (9in) version of the original spring for comparison.
You have to print this with the same settings like the original.
(1 perimeter, no horizontal shells, no infill).
But it´s important to slice it with a low first layer to prevent errors at the print. Therefore ensure that you have a accurate leveled print bed.
My first try with 0.2 mm layer height and 0.35 mm for the first one produced a bad first layer. The second try with 0.2 mm for the first layer worked fine.