I have just finished knitting a sweater in undyed yak wool to a pattern I had previously used successfully for a sheepswool one. The sheepswool version came out a little smaller than I had planned, but as luck would have it, it was a perfect fit on my son, to whom I have now given it. For the yak wool version, which I plan to wear myself, I went up one size on the pattern but it ended up up several sizes bigger despite the yarn being more or less the same thickness. I would like to try shrinking it. Any tips?
I now realise, belatedly, that the characteristics of the yarn, not just the needle size and thickness, can have a significant influence on the size.
In the pic the yak wool version is below the sheepswool one.