These are common on the modern railway network, they are used to supply power to heating equipement that stops points from freezing.
I have been meaning to do these for a while but was unable to find any drawings until recently. An article in September 2022 Hornby Magazine also helped me with this project.
This item has been designed at OO gauge, 1/76.2 scale. For HO Gauge print at 87%, 1/87 Scale, For O Gauge UK print at 175%, 1/43.5 scale, For O Gauge International print at 158%, 1/48 scale, For N Gauge UK print at 51.5%, 1/148 Scale, (Caution: I have not test printed this in N gauge scale).
Examples in the photo's were printed on a AnyCubic Photon M3 Resin Printer
I recommend printing this items on a 3D resin printer to get the best resolution print, in OO this is quite a small item so some of the detail might not show when printed. As per normal with my designs there is a balance between accuracy and printability, hopefully not affecting the design of the model too much.
If you like my designs then please would you support me through my Patreon account - https://www.patreon.com/PJD1974, any money raised helps me research, design and develop new items for me to share. For £1 a month you will give me basic support and for £4 you will get insight into my new designs and be able to contribute with my future projects. Patreons get upto 40% off my models at CGTrader by using coupon code listed in my patreon account.
If you would like a particular item that isn't listed here you can request for me to do a project for you via cgtrader.com. Please be realistic.