The Early Steam Days
By Fred Boland, Machinist 1928-1980
Bayshore Shops, Southern Pacific Railroad
In the earlier steam days when there were more steam engines with the flat slide valves around, we would have to recondition them by filing and scraping their running surfaces. We did this by rubbing a trued faceplate with lampblack over the surface and then filing or scraping the blackened high points until eventually the surface was black all over. Then we would do the same on the cylinder casting surface, maybe running the valve with lamp blacked surface once or twice on the cylinder surface for a final truing.
Generally there were three plates. I have forgotten the order of spotting to true them up, but it went something like this: Two were spotted together, then the third with the first, the second with the third and so on, till they all spotted black all over with each other. It didn't take long to realize that holding at least one plate unused would simplify the next time when you spotted a worn plate against the unused one.
The same reconditioning was done when an exhaust stand was taken off so the boiler flues could be taken out, cleaned and examined for weaknesses and put back in and reset. Flue resetting was a government requirement, every 48 months within five years.
The exhaust stand was directly under the stack. The used steam would come through passages from the cylinders and through the stand, through the petticoat pipe which was a downward extension of the stack to within a few inches of the stand, and up the stack itself. The stand had two thin crosspieces which sharpened the exhaust.
Unlike the valves, the stand was spotted roughly and then ground to a bearing and bolted down. Sacks were stuffed in the cylinder passages to keep tools from being lost and also to keep the filings from going where they would cause trouble.
The piston valves of more modern engines eliminated all this monotonous work, although the exhaust stand was still taken off to get it out of the way.
In 1929, one ten wheeler, a 2300 number in commute service with piston valves, gave us an especially bad time. The exhaust had a wet whooshey sound, the engine was loggy and sometimes even stopped altogether. We ran the valves over and they were O.K. We blew the engine down, took the steam dome cover off, went inside and found the throttle mechanism was O.K. as well.
Then John Nelson, who had bolted the stand down, remembered something. He had forgotten to remove the sacks!
(This story made it to a long forgotten SP Bulletin of 1929 in a more abbreviated form.)