Joe (TwinTubDexter) asked:
'What is different about a "quilting" model sewing machine?'
In addition to what was said above, two other characteristics used to be center front before all the different stitches (mechanical or electronic) and accessories showed up: on one hand, there were machines like the Singer Featherweight, which were on the small/light side, great to take everywhere and for
piecing or patchwork -- when all you are doing is joining smallish pieces of fabric into a block, particularly when a bunch of people get together for classes, workshops etc. A lot of people used to piece by machine and quilt by hand, particularly in quilting bees around a big quilting frame. On the other hand, when one
quilts by machine, a longer arm is more than just practical -- it's very hard to quilt a large quilt in a Featherweight, possible to do a queen/king quilt in a standard machine, but "quilting" machines like the Pfaff Quilt Expression on Reply #78 (and similar sized machines) make it much easier and faster, because you can just roll the entire thing and get the roll to fit under the machine arm, which is longer than standard.
Then there are quilting machines that not only have a very long arm, but you can set the quilt in rolls and run the machine from side to side, which is what professional quilters use -- one makes the patchwork and sends it out to be joined with a backing and batting (which, surprisingly, is what a lot of people do: most quilters enjoy the piecing way more than the quilting). See link for one example.
http://www.handiquilter.com