Here’s a picture of a Singer Automatic Zigzagger 161157 ready for action yesterday on Elsie’s treadle 201K Mk2.  Check out how it clamps to the bottom of the presser bar just like any presser foot does, and how it’s driven by that chromed arm which comes forward and slots round the needle clamp …

So how, you ask, does this marvellous all-metal, all-mechanical device make a straight-stitch machine do a zigzag stitch?  Easy – the needle stays put and the work zigzags.  No, seriously, that’s how it does it, and it works a whole lot better than you’re thinking it will.  Admittedly it does take a bit of faffing about to get your tension and presser foot pressure spot on, but that’s really just fine-tuning the stitch it makes straight out the box.  Here’s a quick video taken while Elsie was testing one on her 201K Mk2 treadle machine …

The stitch length control on your machine works as normal to set how many zigs ‘n’ zags to the inch, bight (width of zigzag) is set and locked on the attachment itself, and once you get the hang of it, you can go at quite a pace

The nature of the stitch it makes is determined by a cam, the red knob of which can be seen in the picture above. The attachment was sold with a set of four of those red top cams, which make an ordinary zigzag stitch and what Singer called a blind stitch, a domino stitch and an arrowhead stitch.

Three other cam sets were also available, the knobs of which are coloured blue, yellow and white, and each of these sets produces four different decorative stitches of the kind you might find useful if you’re making a cute little retro frock for your first grand-daughter and you’re in a silly mood.  But gosh, you should see the prices those cam sets go for!

Anyhow, here’s some more pictures.  Both these and that video are actually of the one I’ve just listed for sale on the accessories page, and hopefully this marks the start of me finally getting that page organised …