I saw this pen advertised as a pen with ink that can be rubbed out with friction. To me friction means heat!! I bought 3 pens for £5 on Ebay, they are called Pilot Frixion. They are nice and fine and the ones I have are blue in colour. They are not exclusively for fabric, but this is what I found:
I drew some of the embroidery stitches to get them in the right place. After stitching my crazy quilt cat I could still see the ink through the stitches, so for my heat source, to get rid of the marks, I boiled the kettle, once it had boiled I held the back of my embroidery against the hot kettle and watched the ink disappear………….. brilliant. I can make as many mistakes as I want, draw as many lines as I want for the embroidery and even after 3 weeks the ink disappeared just with the heat from the kettle, and I get a cup of tea as well.
These pens are brilliant and I know that I don’t have to get my work wet or damp to get rid of the marks as I did with the soluble marker pens. And I don’t have to damage anything by rubbing like I did with the tailors chalk. I will definitely be using these in the future for all of my transferring on to fabrics.