What are decorative cams?

Question

I found a very cute metal tin at the op shop with 'decorative cams' printed on the lid. The tin is about the size of three slices of bread stacked one upon the other. Inside it I found about twenty circular plastic things resting in metal slots which look like they would attach to something - perhaps a sewing machine?

What are they, and how are they used?

Answer 1

They are exactly what the first poster said they are: for use in sewing machines, as a manual way of creating decorative stitches, before computers made them obsolete. They were made in both plastic and metal.

Each one made a different type of stitch and they usually only fit one brand/type or model of a machine.

You'd switch them in and out as you made the different stitches and they were like manual gears or cogs, which directed the gears inside the machine and helped move the arm the needle was in, to form the stitch pattern needed.

Very old school!

They sell sometimes on ebay, but not for much, unless they are a complete set and come in the original box and fit a rare or hard to find machine or the machines they fit are still in use.

See here for an example:

http://www.tias.com/cgi-bin/google.fcgi/itemKey=1922928828

Answer 2

They are what sewing machines used to use back in the day, to make decorative stitches, before the new computerized machines came out. They're pretty much obsolete... unless you have the particular model sewing machine that they will fit.