A few weeks ago there was a thread about using the Pilot Friexon gel erasable pens to mark your quilt lines. I found the pens at Target, package of 3, black, blue and red.
First of all, I love the way they write on paper.
Next I tested them on fabric, I used (washed in Tide laundry detergent without fabric softner) dry, white, bleached muslin.
I drew a line across the fabric in each color. With a permanent black Sharpie, I blocked off 3 sections.
Section #1: erased with the attached eraser on each pen.
This sorta smudged the color, stretched the fabric, but didn't completely remove the line.
Section #2: Ironed the lines without steam. All three lines completely removed.
Section #3: Washed the lines with Suave shampoo (that's what I had at the bathroom sink, was too lazy to run to laundry room for laundry detergent). The lines faded considerably but didn't completely remove.
I then placed the entire piece in the washer, laundered it like I would a finished quilt then air dried it.
Section #1: The erased lines almost completely removed, all the smugging completely removed.
Section #2: Ironed lines stayed gone.
Section #3: No change in the lines.
Then I put the piece in the freezer for about 5 hours.
All the lines Returned, section #3, the lines washed were a little fainter, but still there.
Conclusion: I don't think I'd mark my quilt with these pens. Like I said in the beginning, I really like the way these pens write, esp. the nice fine line. I hope I haven't broken any restrictions by stating brand names, but these are the products I use.
Then I thought maybe using a white eyeliner pencil for marking, works well, but the point is too soft and kept breaking, marks well without smudging and washed out well.
I'm by no means a scientist!!