"...the back of a saw blade is sure to work..."
The teeth of a hacksaw blade work even better. The rod won't last as long, but if you really want/need some sparks, use a sawblade...
Hit the teeth on a grinder or with a file just enough to dull it but leave the teeth. Still gives more spark but won't tear it up as bad as sharp teeth.
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Depend on yourself, help those who are not able, and teach those that are.