I would like some advice from you guys who know sound systems and steam locos.
I am buying a 4-6-2 HO model that will come with a QSI sound system factory fitted. I want to put in the sound of the loco slipping on start.[8D]
First of all do you know the noise I am talking of? One or two heavy start up “choofs”, then a rapid succession of “choofs” until they get it back under control. Too hard to describe.
This is really a carry over from another thread about fire up time for steam locomotives. Mark Newton recounted some experiences with the class of engine that I am getting the model of. Topic 65864. http://www.trains.com/community/forum/topic.asp?TOPIC_ID=65864
For the model I am buying see http://eurekamodels.com.au/. The C38 Pacific engine is the one that Mark says is a slippery loco.[:p]
I have a string of questions:
Did you have slippery locos in the States too?
Has anyone put that sound into a QSI system?
If so, where did you get it?
What suggestions to get the wheels to slip and run the sound while the wheels slip?
I am a novice in DCC and sound. I am hoping that all you experts out there can give me a Noddy’s guide on how this might be done.[?] Thanks in anticipation.
Yeah, I know it’s probably the wrong forum. It is partly prototype information so forgive me.
The only way you will get that to happen with a model locomotive is if you keep the values in CV’s #3 and 4 (acceleration and deceleration, respectively) to a value less than about 10, maybe closer to 7. Then, you will need to place the locomotive under just enough load on start-up, using carefully weighted cars, to cause it to slip initially and then to bite when you reduce the throttle setting somewhat. You would slowly dial in a speed step of 1, followed by 2, then threee, then zip it up to about 15 for a second or two, and then reduce it to 4, and so on.
In other words, you will have to simulate it manually, and the sound chip will merely cause the chuff rate to match the driver rotation rate, which when you quickly dial in 15 will speed up with the hopefully spinning drivers. Otherwise, the QSI chip has no provision for the effect you want.
Realistically, slippery drivers was and is; a highly undesirable condition when starting a passenger train…it jolts the passengers; especially those who might be dining or sleeping. The resulting change in momentum affects the slack and run in/run out on couplers making for a very rough ride.
If the President of the road or some honcho is on aboard, it can result in a demotion or some other career move to another division or back to freight; usually slow coal
Mark, a question. Are you basing these remarks on any practical footplate experience, or simply what you’ve read? I ask because all of these remarks are arguable, at least in my experience. There are some wheel arrangements that are inherently slippery, and specific loco designs that were slippery due to low factor of adhesion, or poor design of spring rigging and compensation. Coupled wheel diameter alone is not a reliable predictor of slipping - the 69" driver 4-6-2s that I ran where considerably more slippery than a visiting 80" driver English 4-6-2 - LNER 4472 “FLying Scotsman” - that we ran across Australia in 1988.
Added to all that, there will always be locations where track geometry, and presence of devices like flange lubricators, axle counters, will contribute to slipping. On many railways, sanding is expressly prohibited around these devices, and on turnouts, etc. I would personally never use sand alone to arrest a slip, but that’s just the way I was taught to drive - sorry, operate - a steam loco. [:)] You also fail to acknowledge that not all slipping occurs when starting a train. Loss of adhesion is just as common at speed, if the right conditions exist.
If all of these factors are taken into account, you would probably agree that no amount of being “seasoned and experienced” will prevent all instances of slipping.
John - Just ran across your thread even though it has been here awhile I thought I would put in my two cents worth. I will start by saying I don’t know a darned thing about steam engines but i do know that the Tsunami sound decoder has the ability to program slipping. I just put one in a Big Boy and adj it to slip some when starting up. Sounds pretty cool I think So the idea is out there. Now if QSI has it in their decoder i could not say. I have two steamers fm BLI and I don’t recall reading anything in the manuals about adj for slippage. Don’t know if this info is any good for you but I thought I would throw it out there.
Terry