Making GWR Safety Valve Bonnets

摘要

It all started at one of the early Midlands Model Engineering Exhibition at the Fosse when Pete Thomas of Polly Models had on display the beginnings of the Collett Goods designed by David Aitken and then the subject of a new series in EIM. By the third appearance of the locomotive at the MMEEI convinced myself that I needed to build one and a start was made. At some point when visiting Pete Thomas to collect bits he said he was having problems with the safety valve bonnet so I offered to make one. I suppose the usual way to make one of these is by spinning to the basic shape and then reforming the bottom end to fit the tapered boiler. However I have very little experience at spinning (it always seems like putting your fingers in the way of a circular saw), but during my time making vintage car radiators I made numerous filler necks and they can be very similar in shape to a safety valve bonnet.