... is a locomotive in the way before taking a picture of the track. 2_060838_540000000.png Hi Jim, I've been trying to find the origin of the BRT3 straight switches, likewise without much joy. However here is a GWR 12ft switch, showing the 4.1/2" offset at the virtual heel, and the actual switch rail in this case 2ft-0in longer at 14ft to the joint. Being GWR this is actually a curved switch, rather than straight. Also the GWR love of joggles is evident, drawn somewhat exaggerated: 2_060852_050000000.png regards, Martin. posted: 7 Nov 2015 12:14 from: John Palmer Sorry, Jim, I should have paid greater attention to your posts, as you had made it perfectly clear that your switch reflected the Caledonian drawing you held. My surmise that CR practice might be to locate some loose heel joints at a chair was partly driven by examination of the pictures in the thread on the CR Association forum to which you posted a link. The impression I get is that CR switch design evolved a good deal ...