A South African team of machinists and engineers at the Keyser Locomotive Works set a record in 2017 for the longest distance travelled by a miniature steam train (one-third scale) in 24 hours: 205 miles. The previous record of 167 miles had stood since 1994. The team has some new engineering tricks up its sleeve and will soon be going for a new record. It is confident that it can tack another 18 to 37 miles onto the previous record.
One of the reasons the team set the last record was its use of self-lubricating Vesconite polymer bushings fitted to the connecting and coupling rods. Vesconite bushing also replaced six of the main crank bushings. These internal, hard-to-reach turning bushings did not need to be repeatedly oiled during the day-long run, which reduced the length of those stops during the record attempt. “You can’t oil these bushings on the run,” explains locomotive owner Andrei’s Keyser.
This is big improvement over the original bronze bushings used on steam locomotives, which had to be oiled every hour.
On the team’s next run for the record, all of the bushings will be made of Vesconite. This will further reduce the time spent oiling bronze bushings.
“The Vesconite bearings have no heat expansion and we haven’t had a problem with heat,” says Keyser. “The engine output was not compromised in any way and the locomotive still runs on the same bushes, two years and many kilometers later.”
Another innovation that will assist Keyser to further improve the record is the fact that he is building the longest straightest track that he can in South Africa. This will let the locomotive run at higher speeds.