Couple of questions if someone has time. 1) where is a good place to get alum for mordanting the yarn? I used cooking alum and cream of tartar but I remember someone saying alum meant for dying is better. 2) what is the difference between picking wool and combing wool? 3) where can i get a pair of combs that are not super expensive but also are not crappy dog brushes (can be dog brushes if actually heavy duty) I have a set of dog ones but they dont seem to work very well.