[John Sabato]

Well, don't FOLD it, but you can increase the curve significantly without doing any damage... spring steel is hard stuff but is designed to flex... a little.

Try bending it around something appropriate (a mandrel) like a half round file using only your fingers if they are strong enough... (some are, some aren't)...and if you don't have the oomph in your hands for that, use a couple pieces of hard wood to shape it over the file by placing the file on a hard surface (curved surface up)..

Another method might be to find a piece of metal tubing whose inside curve is close to the shape you are trying to achieve or a little tighter and place it on the inside and then use a pliers padded with cardboard or leather to conform it to the inside circumference.

Remember that a little squeeze goes a long way... don't try to over do it... better to take it in stages than over bend it...