Anyone have any advice on what pen to use for a signature quilt that can hold up to a few washings?

Try a SHARPIE by Sanford. Available just about everywhere, even Kroger store. You might also get the kind made for putting name on kids clothes for camp.

I use a Micron01 Archival ink pen I bought at the LQS. Before that, I used a Rub-a-dub Laundry marker.

Sharpies bleed and fade, not recommended for fabric if it's something you want to last a long time. Use a Micron pen and don't forget to heat set it. Follow the directions that come with it. Lots of colors, several different thicknesses and they are archival.

Some require heat setting to really stay in. Be sure to heat set it if required or if you don't know.

this is what i use too

i didnt know about heat setting

Micron Pigma pens .o5 is best and i always heat set just to be sure. been using them for years.

micron pigma pens; they are permenent, acid free, will not bleed (sharpies bleed). they are made for writing on fabric with a fine point.

No doubt about it! Micron pigma pens and don't forget the heat!