Hi Big Monster, not wanting to pour doubt over the previous replies, but there are plenty of tiny details to your question that will make a world of difference, depending on your intentions.
From personal experience, I dislike hacksaw blade strikers as they tend to bite more material off than is really necessary to get the job done, they also leave deep gauges in the rod which,I find, leads to faster corrosion. That said, I do have a jig-saw blade that I have covered the teeth in hot-melt-glue and formed into a bit of a handle.
I prefer a large handle - for those times when my hands are getting cold - the tiny key-ring sized ones are difficult to control with cold fingers.
The best I've used so far was made by "Mad Dog Survival" Youtube channel but selling on Ebay - a ceramic piece set into a large wooden handle - easy to control and big fat sparks every time.
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www.etsy.com
