Others have given good advice- you do not need springs and the key is to use a good quick release. I like Shimano steel internal cam only for my fixed and single speed. I even use them for single speed mountain biking and no issues. I am working a Bianchi Project 5 with "semi-horizontal" dropouts and thought I would need to trim the axle for a little more play, but this one magic geared it - 64 GI road fixed and flip for 55 GI singlespeed dirt and easier MTB trails on 29x2 tires. It works because there are 2 front chainrings to accommodate differences in the fixed and single speed sides of the rear hub.
Go for it and post pictures please.
Tom Palmer
Twin Lake, MI