No it's not necessary as Bill said, but you will be so much happier you have one later on down the road if you get one. As they say, "Buy once, cry once." I've learned (still learning in fact) the hard way and have cried quite few times now

lol.. A number of times I've been in too much of a hurry and would just get what I could afford at the time so I could hurry up and "go out and play", and have ended up regretting it later on. However, I didn't have a steady income for most of those things (and very little when I did), so I don't feel too bad, but if you do have an income, just save up a little bit longer if ya need to to afford the variable speed, you will not regret it.
BTW, I still don't have variable speed, but I sure wish I did. But I'm glad I at least have a "slower" motor (1750 rpm as opposed to ~3600 rpm) with 3 step pullies, that way I can slow down the grinder down to a "relatively slow speed" compared to single speed direct drive grinders. I'd rather have the lower rpm motor with step pullies, but with variable speed, you get more range with a higher rpm motor.. anyway, just something to think about.
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ETA: Most guys here are saying they mostly use the high speeds for profiling and grinding bevels.. I can understand the high speed for profiling, and maybe for roughing in the bevels, but for getting them crisp, clean and tuned in, I myself still need a ways ta go to be consistant.. so the slower speed is a MUST for me. For some guys, grinding bevels seems to come more naturally after practicing a bit, but for others, not so much, and it can take much longer to get it "down".
I however, usually end up taking too long when it comes to finishing most of my knives, so I pretty much loose most of my muscle memory by the time I start grinding my next ones, so that may be why I am all for the slower speeds you can get with a VFD. But you will shorten your learning curve by starting out with slower speeds so you can better observe what is happening as you grind. Just
one more thing ta keep in mind

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~Paul
My YT Channel
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