Ok, the fabric eraser did help a lot. It still did not remove the darker chalk marks but it did lighten it a bit. It's kind of hard to see the chalk marks in the picture but it's the best one I could get after a few attempts. The marks are on either side of the stitching, though it was a thin line of chalk when I applied it. I'm thinking that the chalk kind of blew out to the sides as the needle and walking foot approached it and then the heated needle and machine bed must have set it. It brushes off so easily any other time so the machine must have just scattered the loose chalk powder a bit. :?
This is before the chalk eraser. I'm still erasing, just trying to take it slow with all the stitches.
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