Sometimes I like to de-nib between coats using 0000 steel wool. Now that I'm using waterborne finishes, I know that using real steel wool isn't a good idea because it can rust. I've tried the grey and white synthetic pads, but it seems like the grey is too coarse and that the white is too fine (does almost nothing). It also seems that the "grain" in the synthetic pads is very inconsistent. Has anyone found a good substitute for real steel wool?