On Wed, 05 Jul 2006 16:48:44 -0500, Andy Asberry
wrote:

On Tue, 04 Jul 2006 08:12:44 -0500, wrote:

Just wondering. I got a push mower with a bent crankshaft. The mower
starts on one pull and runs great except it vibrates so bad that it's
near impossible to hold it for more than a few minutes. I heard they
have some sort of jig to straighten them, but also heard about doing
it with a hammer and wood block. Is this really possible? If yes,
where does one get a jig, or what is the method with the hammer?
I dont need to get it 100% accurate, but right now it's beyond using
as it is. It's just an old beater so I am not willing to buy a new
crank unless I happen across a cheap used one. But if I can
straighten it for a few bucks, I'll give it a try. The worse I can do
is destroy it, and it's junk right now unless I get it straighter.

You'd want to anneal it first, hammer it to shape, and then
harden it again. If you know what your doing (which I
don't) it shouldn't be hard. If you don't know what
you're doing, then you'll have metal fatigue around the
bend, which means (as another poster pointed out) that
the shaft will shatter at some random time, at
which point the blade will turn into a propeller, and
chop you off at the ankles.