Three years ago a guy at a Ren Faire saw me about to sew my sleeve on backwards and just said "you're gonna want that seam facing the other way" before walking off. He saved me from what would have been two hours of picking out stitches in a hot tent while wearing full velvet. I still don't know his name but I think about him every time I tack down a sleeve. That fabric store lady deserves a statue.

Heard a guy on a woodworking podcast say that jigs are basically just time-saving mistakes you learn to build, so I get the struggle. For a one-off job, I usually buy the cheap tool and move on, but if it's something I might use again later, making it is half the fun, lol. That said, three twisted handles sounds like your grinder setup was fighting you, not the jig. Building your own for $12 in scrap is a win if you've got the spare time, but honestly, my Saturdays are too short for that kind of patience anymore. Probably would've just ordered the jig and used the saved two hours to actually make the thing look good.