OK. I'm either totally full of it or not communicating my thoughts properly. This discussion started because Barrettscv was thinking about buying a new steel fork with a threadless steerer, and both SOMA and Surly advised against threading the steel steerer on their threadless forks because the wall thickness of the steerer tubes was too thin to safely thread. The vendors also said that standard 22.2mm quill stems wouldn't fit those steerers because they would be too loose.

Light 1" threadless steel steerer tubes have 1.6mm walls at the crown end and 1.1mm walls at the stem end (I thought it was 1.0mm, but it's 1.1mm).

I think everybody agrees that the normal 2.3/1.5 threaded steerer is what is called for here in order for a 22.2mm quill stem to fit properly, and that's why Barrettscv started the thread; he was asking if the thinner walled steerers in the SOMA and Surly 1" threadless forks could be replaced with the 2.3/1.5 steel steerers.

I thought the thread had ended when Barrettscv said in post 19 he would have a new custom fork built over the winter.