Bevel tool producing strange results

Attached is a blend file with just the object I’m trying to add a bevel to however the bevel tool is producing highly distorted and inconsistent results. I was hoping someone might know why this is so and how I may be able to fix it. The edges I’m trying to bevel are currently selected and the bevel amount I’m aiming for is 0.002. It may be worth noting that I created this object by applying several curve modifiers to several corresponding vertex groups within this mesh object (in case this helps narrow things down for someone).
Thanks in advance.
Bevel Issue.blend (1.78 MB)

For now enable Clamp Overlap C to fix it.

Thanks ramboblender. I’m a recent convert from Blender 2.49 and was using the bevel operation found when hitting the ‘w’ key. Didn’t realise it was now a modifier as well.