Pick up a rock
rub it over your edges
depending on the coarseness of the rock you might want to do this several times...
(i wouldn't suggest the use of a gummi stone, they're used to detune filed edges, to get the sharp brims off but your edge will still be sharp as fuck and catch an edge... really think of it, you'll be sliding metal rails with your edges, you'd have to be quite a moron to seriously fuck your edges up, doing more damage with a handfile than with 10ft metal rails...)