I may just have solved this free style machine embroidery issue and cheaply too...
If you go to
http://www.amazon.co.uk/EMBROIDERY-DARNING-BROTHER-JANOME-MACHINES/dp/B0076AL3QW/ref=sr_1_2?ie=UTF8&qid=1363781778&sr=8-2
This foot fits lots of machines of the low foot shank variety.
I have a Frister Rossmann Cub4 from the early 70's and it fits mine with a minor pin tweak...
My foot has only just arrived and this is my first attempt to write my name... well ish so I'm sure with a bit of practice everything is possible...
I am one very happy little bunny...
For £ 3.44 inc P+P a grand little foot... put your Feed Dog down... grab yourself some decent weight fabric and off you go....
I can see a lot of fun ahead...
S's are a bit tricky!
smiles Cass x