Since I began quilting 16 years ago I have always used a water erasable blue marking pen with no problems with removal. The biggest problem being pens drying out, it can become quite costly when you are marking a large quilt. While out shopping earlier this week I came across the Clover water erasable blue chalk pencil which I thought I would try. Below you can see a picture of my marked sample ready to stitch. The feather pattern is from Anita Shacklefords book Infinite Feathers.
I stitched the feather using Mettler Polysheen in the machine using a 70/10 embroidery needle and the Bottom Line thread in the bobbin. See photo of completed sample below.
I was amazed at the amount of chalk dust that collected on my darning foot!
And below we have the finished piece after soaking in cold water, unfortunately there is still evidence of the blue chalk …..has anyone else used this pencil who could offer ideas for its’ complete removal? I will stick with the old faithful, the water erasable blue marking pen!
Pieces of Pye 
I haven’t tried this type of marking pencil before. Maybe try googling it to see if any chatlines pop up.
I’ve sent my houses off for the swap. Will have to wait and see what I get back. Should be an interesting neighbourhood.