I've been using the Sawzall a lot over the past month. Mostly for nail cutting in tight spaces during the demolition phase of the project. The blade tends to get bent right where it attaches to the saw and that's where it fails. First you get a stress crack and then a few minutes later it breaks off. They all do it ......
The Sawzall saves so much on labor that the blade cost is insignificant. I usually just charge them off to the job like i would a 2 x 4 or a pound of nails.
The Diablo blades are good as well as the Milwaukees. The Irwins are okay .... nothing special. If you're cutting cast iron it would probably be better to go to a 4" angle grinder. A Sawzall isn't the best tool for that job.
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