For a couple of upcoming projects of mine I needed a source of some GWR type chimneys. The original plan of mine was to use some bits from the excellent range of castings that Nick Tilson of N Brass produces. The thing is his castings are in Brass and I wanted to do the distinctive copper capped chimneys that so many GW engines had so this is my solution...
First I found some great little blog posts that Paul has done HERE which show in fantastic detail how he produces them. This seemed the ideal way to try making my own but, once again, they were Brass. My idea was then to do some research to find out what the best grade of Copper was to machine as there is a good range of alloys available, some of which are a pain to machine. The final decision went to some C109 Copper and was duly ordered via Ebay HERE
Once the Copper had arrived and I have time I firstly scales a works drawing for a chimney which provided me with the dimensions I needed so then I promptly made a start. My plan was to make the whole chimney out of Copper so once it is painted the top could then be polished up, looking all GW.
As per Paul's posts the next step was to hold the chimney in position and then form the base around a suitable bar similar to the boiler diameter. I used (ironically) the copper bar which was used to make the chimneys from and my manual milling machine.