Except that’s the wrong word, because apparently “convertibility” refers to the ease with which a currency or a security can be traded for another.
So it looks like there isn’t a handy word to describe the ease with which Singer sewing machines of the 1900’s to 1950’s can be converted from hand-crank to pedal power to electric and back again, which is a bit of a shame really but there you go. Despite the lack of a word, though, it’s still surprising what you can do with these things.
Take the model 66 that’s on the kitchen table right now waiting for a final polish before we sew it off ready for sale. In its present form it’s a hand-crank portable, which is to say that you turn the handle to sew, and when you’re not sewing, it lives in a case. Twenty minutes work will turn it into an electric portable, powered by a refurbished Singer motor of the correct type, controlled by either a period Singer foot pedal or a modern one. Or we can fit a good quality modern Japanese motor instead.
If you fancy pedal power though, an hour will see that same 66 fitted into one of the two types of treadle base we currently have, and if you want to cover both bases, the machine can go into a treadle base but still retain its electric motor. The same goes for any of our 66’s or 201’s (and indeed for the 27/28’s and 15’s which we don’t get involved with). Versatility or what?
In fact the only variant we can’t actually offer at present is a 99 treadle. But we can put a 99 in one of the tables made specifically for it, into which it folds away when not in use …