After looking for a suitable steering wheel on the internet without success, one was made up. Lots of ready made wheels but too large, too small, near enough the correct diameter but with a rim much too thick for scale etc.
A local metal fabricator advertised various scroll work items for gates, garden furniture and so on. A visit was made expecting them to have a ring rolling machine. "Never heard of one" was the reply from one staff member. He called another older person, same answer. When I asked how they made the scroll work they advertised, "We don't, we buy it in ready made from China".
Mr Showman had previously mentioned that a friend might be able to roll a ring up. Within a few days I had a 7:1/2" ring x 3/8" section. The hub is a previously drilled cap screw with the spokes from flat strip jammed between two nuts after having a bend made at the inner ends. After trimming the spokes to length and clamping down Chris welded all the joints up. Thanks Chris. I keep thinking I ought to buy a welder but it probably wouldn't get much use.
Grinding the welds down was easier than expected, especially around the hub, using a Dremel. A slot was cut in the cap screw head for a roll pin which together with a nut held the wheel onto the column. Two short pieces of tube were pressed / hammered over the nuts and all the joints blended in with filler.
The last photo shows the pin resting on the head of the cap screw which is the column bush. This still needs a sleeve over it to finish off. Also a cap made for the wheel center. I should have made the spokes with a steeper angle but too late now. My great grandson, pictured above, liked it anyway.