Mickey2

I have been trying to sort out the all metal models too, at least all metal inners (the odd knob and handle on a lever is allowed to be plastic and still be called "all metal" in my way of thinking). The 500 and 600 series are sort of on a case to case basis; there are reports of people buying identical models and finding one machine with all metal gears and the other with one or two plastic gears. There was a thread on this a few months back too.

I'm not too strict on the all metal requirements, because some of my favorite swing needle models have one or two plastic gears; they are 50 pluss year old machines still running fine with original parts. Some plastics have aged better than others, and for many models there are better quality replacement parts available than the original parts. In some cases there are replacements available in both steel and plastic for the same part. These models can be well worth fixing up.

With Singer and some other brands you will find phenolic/resin type plastic as early as the 1920s (I think the 201-2 was introduced in 1928). Buy the early 50s I suspect Singer must have experimented with the various new plastics. All open arm Elnas and Berninas I have seen have had a plastic gear or two, machines dating to early 50s. Flat beds versions of similar models are some times all metal, and of a sturdier construction (at least the parts under the bed).