How to straighten blades?

[Fordiesel69 221]

I have a 48" SD deck in which all blades are worn equally so I do not want to replace just one.  The center one is bent or bowed so it scalps the middle.  How can I straighten this safely?

[DoctorHfuhruhurr 136]

I used heat and a vice to straighten mine and didn't have an issue.  I would just check carefully for cracks and scrap it if you find any.  

[doc724 924]

Support the outer ends on a couple of bricks or 2x4's and smack the middle with a 10# sledge hammer.  You are not looking for perfection, just better than it was