... 2" clearance (i.e. 4.75" offset) shown. There are 4 fish-bolts shown and some sort of fishplate. How this is attached to the chair isn't clear, but I would imagine some sort of back spacer block to maintain the 2" clearance under flange load. I have been searching for drawings or photos of such chairs, so far without success. As you know, the usual practice of photographers is to wait until there 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 ...