Okay, so here's how the experiment went.  Here is the pen markings on the fabric.  I just noticed I spelled "quilting" wrong!  (Bad Spellers Untie)!  So I'll use the pen for "quiling"!

 Anyway, this is what it looks like when marked.

 Next, I applied a hot iron to the markings and, as promised, the marks disappeared!  No sign of my "quiling lines"!

Then I put it in the freezer for about 5 minutes.  If you look closely you will see the markings.  They aren't as bright as before but they are there.

So I threw it in the washer to see if the markings would wash out.

They did not wash out completely.  

So, what to do?  Do I use it to mark my quilts?  Maybe.  The only reason my quilt would get that cold is if I were shipping it somewhere.  And I'd only be worried if I were going to show it.  If I'm making my "Masterpiece" I will use another form of marking.  Truth be told, I prefer soap slivers to mark but the lines are really thick!  I do think I'll use these pens on a quilt in the future but not the hand pieced Feathered Star!

Today a friend of mine who recently started quilting came over to start the Craftsy Block of the month.  We took waaaaay longer than needed but had a good time!  I really didn't want to go out and get MORE fabric for this project so I hit my stash.  I had some Aunt Gracie fabrics put aside for a future project I don't think will be started any time soon so I'm using them for this project.  I'm hoping to keep up with this and have the top done by the end of the year.  Two 12-1/2" blocks (unfinished) a month should give us a nice sized quilt at the end.  No pictures of the finished product so kind of a mystery quilt!

The first 2 blocks

Happy Stitching!