Smoke

[sandman8355]

Any secret to getting the smoke to work on  the U.S.R.A. 0-6-0 in HO gauge?

[Bucksco]

Not sure how old it is but some of the newer 0-6-0s with smoke have an on/off switch which is located in the cab - check the instructions.
If not you might want to contact the service department to see if they can help.

[ACY]

Any secret to getting the smoke to work on  the U.S.R.A. 0-6-0 in HO gauge?

It is possible that the smoke unit is broken or not functioning properly. Generally though you need to run the locomotive at three quarters throttle to get it warmed up, and you probably need to maintain at least half throttle to maintain an appreciable amount of smoke, and less and the smoke you would get would be negligible to non-existent.
Basically though my only advice is to run it full speed and if that doesn't work it probably is broken or toggled off as mentioned by Yardmaster.
As an aside, one reason many are weary of using smoke is that you likely will have to clean the film/residue off the track frequently to maintain good conductivity.

[bbmiroku]

My DC 0-6-0 and 2-6-0 both use smoke fluid, but I have to run them for a while at max voltage for smoke to start puffing.  Then, very slowly throttle down a bit.  A sudden voltage drop cools off the coil too much and it stops smoking.  What I have figured out, though, is that the worm gear is actually creating a draft towards the rear while in forward that is sucking air through the smokestack and limiting extremely the amount of smoke produced.  When I run it in reverse, there is plenty of smoke at almost any voltage, because the worm gear is pushing air through the smokestack.