Garden Railway Forum

Phil,

This is an interesting thread. I'm not an engineer but can say from observation of standard gauge engines that mechanical lubricators use much less oil than any other type. Your mechanical lubricator is fantastic. (As an aside priming a mechanical lubricator on a standard gauge loco after oiling is a pain in the proverbial)

I've often wondered why mechanical lubricators are not seen more often in our scales? I guess they are more complicated than the displacement types and consequently increase the cost? Perhaps there's a commercial opportunity for you?

I think the reason we don't see mechanical lubricators on commercially produced locos in the smaller scales is down to cost. They contain a fair amount of small parts, something that lends itself to manufacturing on a CNC swiss lathe. Unfortunately those machines have longer setup times compared to normal CNC lathes (I work with both types) so making a small qty of parts is very expensive.

dewintondave wrote: ↑Thu Dec 06, 2018 10:30 pm Well said. Worth mentioning is that steam oil helps provide a seal

Condensate does also, though slightly less than oil. Our small stuff doesn't have piston rings, but often there are small grooves (labyrinth grooves) around pistons and when fluid gets into these groove is makes a seal almost as good as a good piston ring. Corrosion isn't much of a problem with brass/bronze cyls. and pistons.

Has anyone noticed, for example on a Roundhouse engine, any differences in the locomotive's performance with less lubrication? The reason I ask is that when I first got mine, I reckoned that the lubricator held enough oil for about three boiler fills. However, I was sure I noticed that on the third run, the engine became just slightly more "jumpy", as in, when one opened the regulator, it wouldn't respond as smoothly and would stay still for longer as the regulator was opened before leaping away angrily. I can't swear to it, but this was my perception, and I started draining off the condensate and topping off with fresh oil at each boiler fill.

Now I should point out that this is a kit-built engine, and therefore was not subjected to the running-in period that Roundhouse gives their factory-completed engines. When it was very new, it exhibited some blow-by of the valves, that is to say with the reverser in neutral, if the regulator was opened, some steam would emerge from the chimney. Now the locomotive has some miles on it, particularly after I have made it pull a flywheel "momentum" wagon, it doesn't do that. The valves must be well seated now. Perhaps it doesn't require as much lubrication now as it did when new. It certainly is an oily little thing. When the regulator setting is changed, especially after sitting still for a moment, it often gives off great puffs of blue oil smoke. I rather like the smell, but missus does not, and the sooner I get some track laid in the garden, the better.

Nothing there that I wouldn't expect from a new loco. There is bound to be a mechanical tightness until it has got a few miles on. That is completely different to any sort of siezing up due to lack of lube. My Roundhouse L&M, supposedly run in at the factory, has immeasurably improved with use, likewise my Silver Lady, which was actually secondhand. I do suspect though that she had very little prior use.

I think reallly we should just think about how much we lube rather than slavishly following a set regime. New and tight, will need a bit more as 'insurance'. Nothing worse on the eye than a loco and rolling stock dripping with oil from end to end.

Yes Keith, definitely smoother with oil