2 or 3 springs for tremelo?

[krackenthorpe]

Can you use 2 springs with a edge instead of 3?

[moebius]

Depends on your string gauge. A light set of strings might work.

[Dee]

Possibly.

2 springs might work OK with .008" gauge strings. If you're using .009" gauge then you'd have to screw the screws all the way in. Even then I dunno for sure, but I don't like putting them all the way in. Last time I tried it I messed up the screw heads and could hardly remove them.

[Nordhauser]

Just use 3.