Last time I checked, we had two. But then I'm only there for part of the year (it's a seasonal gig). Also they were refered to as overlock machines, so I'm not sure if they "serge" as well (which I think just means they cut the excess material off... Am I right?).
You can have an over-lock stitch that does not cut off the excess, but that would be a very old machine. For those that don't know a
serger has, typically anywhere from 3-5 needles, a blade for cutting off excess material prior to it being stitched, and usually a
walking foot.
The needles work in a complex ballet of engineering wonder to create that really cool stitch you see on the inside hem of a t-shirt. One of the nice things is you can take a piece of fabric with a very irregular
edge, run it through a
serger and you get a piece with a straight
edge < provided you ran it though straight> and a nice "over-locked" stitching which will keep the fabric from fraying. The blade is extremely sharp, it's basically a razor that saws up and down as the fabric moves through. The "
Walking foot" is a feature typically found on machines that are used for stitching thick fabrics. A
Walking Foot is a presser
foot that moves forward and backward with the action of the "
feed dogs" <
feed dogs are the funny looking teeth that move up and down and back and forth to move material into the needle. In a regular machine the presser
foot < or pressure
foot> ( I prefer presser) just presses down on the material to keep it against the
feed dogs, on a
walking foot the presser; pushes down to pinch the fabric, moves toward the needle with the dogs, then raises up moves away from the needle, then presses down again to pinch more fabric. This is very helpful when working with thicker fabrics, such as when you might be sewing
Drapes let's say. Without a
walking foot the top piece of fabric can tend to bunch up causing the two pieces to creep against each other, by the time you get to the end of a 20' hem the pieces might have moved as mush as 2 " in relation to each other, this would be bad.
There are tons of cool machines in the sewing world I like
Blind stitchers, they do the seam down the side of your jeans, which is a lot of work when you think about it. Devoted Ziz-zag machines, like the one I now own for doing draperies, and other gear < the guy I got it from was in the Climbing harness feild, this baby can sew through 4 layers of 1/8" nylon
webbing!>
Caution If you're a TD and you know how to sew, Never let anyone know or they'll always
send you to the costume shop to make
curtains. While this can be theuraputic, it can result in Stitch and ***** disease.