Punching holes in 28 gauge tempered spring steel will be easier than in 16 gauge mild steel, but the hole puncher tool is likely to fail quickly when used for an unintended purpose such as this. For a hobby project, one should expect that punching thinner steel may damage the tool over repeated use and require replacement.

1. Is it easier to punch a hole in 28 gauge tempered spring
steel than 16 gauge mild steel?
Yes, it will work, but expect the hole puncher to fail quickly.
I always bid a job, in this situation, as though i'll have to replace the tool i'm using for a purpose
which it wasn't intended. If it's a hobby thing, just know you could damage the tool, and might have
to replace it after a while.
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