The tire hammer is great only if the rim and tire haven't been together for 30+ years......
I find that the best way to break down really nasty, rusty old tires, is to lay them flat on the ground and using the high-lift under the 715 bumper, push them down and get the lock ring off.
With a nice clean, painted rim, and a newer tire, then the tire hammer will bring them right off no problem, otherwise, you'll probably end up beating yourself silly, working up a sweat, and even dinging up your lock ring to no avail.
And as far as once its off, get your new tire, tube and flap and put it back on yourself. Yes, you do need to be careful, and clean with it, but these rims won't kill you, if you install the lock ring properly. Once the ring is seated, and the tire slides up over it, there really is no way it can come off, and when its installed properly you can tell just by the appearance. It "fits" correctly all the way around its circumference.
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