Hello there.For a grind,You can use an angle grinder or a pen-knife if you dont trust the angle grinder.But it all depends on rim's and pad's your using.For example,If your using zoo! pad's,DO NOT give your rim a harsh grind,Because the pads will last around at least a day.If that doesn't make sense to you at all....Here's what I mean. Soft compound pad's=Smooth rim with/Without tar or a very light grind. Hard compound pad's=Harsh grind with some pad's,But some hard material work well on smooth rim's.E.g koolstop's work better on a smooth rim. Medium compound pad's=Light grind with tar? Or could be decent with just a light grind. Some rim's go very weak when grinded,Like some of the old monty rim's. I could be wrong.If I am....Someone please correct me.