MPR wrote:Does anybody have a suggestion for a decent replacement dome for the 14xx? I haven’t found a suitable one yet. The moulded part on the Airfix body has a very significant taper on it.
Sorry, I'm afraid that this isn't a stone that I chose to turn. I've left mine with the original.
Looking at the model, and then the photos and the General Arrangement drawing of the locomotive in GWRJ no.22, I would identify a slightly different issue to be corrected.
I have measured that there is a taper on the dome of my model. Probably deliberately there to aid the release of it from the mould. However, with digital calipers, I reckon that the amount of the taper from top to bottom of the "parallel" section of the dome is only 0.05mm on each side. That's scarcely visible to me.
What became more noticeable as I looked is that the whole dome seems slightly malnourished. There is no marked dimension on the GA, but it looks to scale at 2'6" in diameter. The dome on my model seems to measure at about 9.4mm in the middle of the "parallel" section. So that is 0.6mm underscale against the prototype, which does have a visual impression if pointed out. All measurement subject to sel-induced manual errors, of course...
So whilst I can't help with a source for a replacement, I hope that you find one that is the right size, as well as without taper.