The problem with a grinding wheel can be heat... If you get the tip very hot to the point of almost a cherry red colour at the tiny end (easily done) then this will remove almost all of the tempering / hardening that was done to this metal at the factory to keep it very hard, so hard that normal steel is soft when compared to these tips.
The hardening process at the factory would be to heat up to cherry red, then when red, to quench in oil. This cools the metal slower than air or water and allows the physical structure of the metal to densely pack it's atomic bits together - meaning a harder then mild steel metal. If you grind to cherry red on a grind wheel, it cools in the air - you just made soft mild steel again! There's more to it than that, but it gives the idea! I, as a gardener, possess some high quality blades from edging shears to scythes and beyond, most are some sort of hardened steel. I use a diamond file on these blades and on my prepping tips - this keeps them hard and sharp and has worked for me for over 10 years. Check out our favourite auction site and don't pay more than three quid for a double sided foldable diamond file. As at September 2019. Hope this helps 🤔😁👍
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