Having seen another railway produce there own sleepers fit for passenger running, we thought we would try the same. After knocking up a mold from some scrap plywood, welding some rebar to threaded bar we were ready to cast.
To make the concrete we opted for a nice strong mix 3:1 ballast:cement with added glass fibre reinforcement. Having poured the mix into the mold it was vibrated to remove any trapped air using a rather rough running Briggs and Stratton engine!
Left to set for a week it was released from the mold, transported to the museum and fitted in replacement of a particularly rotten timber sleeper. This will remain here for a bit to test its strength and ensure it doesn't crack with continued use and high loads. Even the colour hasn't turned out to be too bad as the ballast used comes from an area of red rock (quantocks?) which gives a more earthy colour than some which give a very light grey.