Anything from a week, including marking and cutting the fabrics (and making freezer paper templates, if I'm doing complex piecing) to a few months. I hand sew everything. I don't work, but on the other hand I have severe ME/CFIDS so I can't sew for as long as I'd like and sometimes I have to take the odd month off. The quilt in the icon is a metre square (full photo at
http://img837.imageshack.us/i/isisquiltfinalphoto1.jpg/), and if we take off the two months I lost due to RSI and tendinitis, I worked on that for four months, including designing, piecing, appliqué, embroidery, quilting and beading.