Dear Andrew,
Thank-you.
From your description, the Proxxon 12 E fits your description.
https://www.proxxon.com/en/micromot/27082.php
My other cutter is also a Proxxon and I am very happy with it, so it sounds like a good choice.
I will wait a day or two to see if there are other recommendations, or opinions about the Proxxon 12E.
Mick
I've got the 12/E, used it for a couple of years now. It's not too bad, but I am not really happy with it. The plastic grip is not really robust, meaning that once you tighten up the bottom arm sufficiently, the plastic halves come apart slightly. The top joint does not properly fix the upper arm, so it is susceptible to pivoting vertically, and this is exacerbated if you cut anything more robust than styrofoam (EPS).
Essentially, I've found straight cuts to be nigh on impossible even using guides. I now it is not really designed for that, but even a bent shape of the wire will not hold properly unless in softer foams, I.e. EPS, so the resultant curves/profiles will be a bit uneven. Based on this, I wouldn't buy it again since I intended to use it for XPS foams, at least not at the listed price, considering you're also looking at the Micromot power unit unless you already have one for your stationary one.