Ok--you lot know what you are talking about with this-----but a couple of questions now
(1) Is low carbon steel the same as mild steel?

(2) do you think the pistons are then hardened after machining (and if so , how?) or are they not hardened at all?

(3) are the later pistons (Hurricane /Tempest) different from the earlier ones (Mk1, Senior, Premier) in how or what they are made from and / or hardened?