Anyone have one of these? Are the "cams" (not really cams but that is only name I can figure to use) that control the automatic stitches nylon? I ask because some of the vintage all metal machines (Like Necchi Lydia) have a nylon one (whatever it is called) and once crack hard to replace.
http://www.ebay.com/itm/Rare-Pink-Se...item2ed55b2643