Yeah, they have these little discs that come in tubes of like 30. They're cheap.
Those, plus patience, work fantastically for me.
You have to be very, very sensitive to excessive pressure or any side-load, misalignment with the cut slot, ripples, vibration effects or anything irregular. Disengage immediately when you start to see that. If you persist, the ...
What you want to use are cutting wheels or grinding disks similar to the ones shown below. They have always worked great for me. They wear down faster than the heavier ones but they're thinner so they cut faster. They do break a little easier than the heavier one too.