Compound Steam Locomotive-Chuff “Rate”

You are correct when the engine is working in compound. When the engine is working in simple, you will hear exhausts from both sets of cylinders, namely eight. Read the following...ALCO Articulated Mallets

However, after a length of time operating in simple operation, the two sets of cylinders will sync themselves together where even though there are still eight exhausts, you will only hear four because they are exhausting at the same time.

@Big Jim posted:

However, after a length of time operating in simple operation, the two sets of cylinders will sync themselves together where even though there are still eight exhausts, you will only hear four because they are exhausting at the same time.

Thats correct!

Didn’t the Y3 start out simple and then transitioned to compound as speed increased?  Did simple provide better traction?

Correct, the Y6b starts out in simple mode and then transitions to compound mode when it gets moving.  I believe the Y3 did the same thing, basically the same locomotive.

@gunrunnerjohn posted:

Correct, the Y6b starts out in simple mode and then transitions to compound mode when it gets moving.  I believe the Y3 did the same thing, basically the same locomotive.

I believe you will find that ALL compound articulated steam locomotives HAVE to start in "simple", otherwise they couldn't start their train.

I wondered about that as all the ones I have looked at seem to indeed start out in simple mode.   If they couldn't start without it, that would certainly explain it!

@gunrunnerjohn posted:

I wondered about that as all the ones I have looked at seem to indeed start out in simple mode.   If they couldn't start without it, that would certainly explain it!

John,

Give that link a read that Big Jim posted if you haven't already, it goes pretty in depth of how the system worked.

Well, hopefully after some track work in Western Maryland.  We'll hear C&O 1309 in both simple and compound this summer.

@superwarp1 posted:

Well, hopefully after some track work in Western Maryland.  We'll hear C&O 1309 in both simple and compound this summer.

Fingers crossed 🤞🏼

When I shot video of N&W 1218 for the Hopewell Productions Video 18 Wheels of Steel  I noticed that the two engines (front and rear) would drift in and out of sync. The locomotive would run for long periods of time with the engines in sync. When in sync, you would hear only four, evenly spaced exhausts. Then they would slowly drift out of sync for a while, resulting in eight sometimes oddly spaced exhausts as the two engines ran out of sync for several miles. You can clearly hear this in several runbys in my 1218 video.

N&W 1218 is a SIMPLE ARTICULATED, meaning she did not use any steam compounding. The boiler fed all four cylinders directly.

So when Lionel or others...comes out with compound locomotives such as the re-release of Vision Line 2-10-10-2’s. They should model the chuffing sounds of the compound locomotive transitioning from simple to compound.

Like this:

1. The loco starts out in a 8 chuff articulated beat.
2. As its going maybe say around speed step 10-20 it goes from 8 to 4 chuff beat
3. Add a steam hiss sound in there during transitioning
4. It stays at the 4 chuff beat till the loco stops.
5. After the loco stops, it resets back to 8 chuff beat articulated chuff.
6. Cycle repeats after starting out again.

This could be used on many other models....

@Dave Olson @Conrail1975

@Bruk posted:

So when Lionel or others...comes out with compound locomotives such as the re-release of Vision Line 2-10-10-2’s. They should model the chuffing sounds of the compound locomotive transitioning from simple to compound.

Like this:

• The loco starts out in a 8 chuff articulated beat.
• As its going maybe say around speed step 10-20 it goes from 8 to 4 chuff beat.

               I don't know how those "speed steps" relate to miles per hour, but except for the N&W Y6 class locomotives, pretty much any compound would be "switching" from simple to compound before 5 MPH (probably more like 2 or 3 MPH). The N&W Y6 class locomotives had a "simpling control" for the Engineer so that he could ad "live steam" to the low pressure cylinders for hard sustained pulls, at speeds up to about 10 MPH (if the Fireman could keep up with the massive steam demand).

• It stays at the 4 chuff beat till the loco stops.
• After the loco stops, it resets back to 8 chuff beat articulated chuff.
• Cycle repeats after starting out again.

This could be used on many other models....

@Dave Olson @Conrail1975

Everything else you have listed appears correct.

Maybe one day the Bud Swearer tapes of the N&W will be made available again. Then you will hear, many times more than Link's recordings, what the Y6's and A's would do, along with some fine whistle artists!

Jim, I would love to hear those recordings.

Who has them now, and what could we do to encourage them to be released again?

Several members of the N&W Historical Society have a complete set of Bud Swearer's N&W recordings, both as cassettes and digital media.  Big Jim and I are just two of about five that have a set.  Unfortunately, the originals were not accounted for in Bud's will, nor have they shown up anywhere, so I'm presuming they are lost for all practical purposes.  I did a detailed analysis of all the tapes (57 pages) so we have a record of what's there.  NWHS acquired all rights to the N&W recordings from Bud's estate back in 2016-2017.  I'm sure Big Jim will back me up on this, but these tapes from a historical standpoint, are probably better than Link's.  The documentation is extensive where Link's was sometimes good sometimes not so good.  Like most things, all that's needed is ambition (probably mine), commitment (NWHS), and money (source??)  to move the project forward.  The content is almost beyond imagination with an extensive pacing sequence of an A starting a train at Bonsack, several recordings of  Y6's switching from simple to compound, and sustained operation of a Y6 in simple on Blue Ridge.

Precision Craft models, a branch of Broadway Limited, made models of the N&W Y-6b which had a function command which could switch the locomotive from compound to simple exhaust.  I don't know if the Broadway Limited Paragon2 and Paragon3  versions of this locomotive have that feature (Precision Craft used ESU LokSound decoders).

Marklin has made some HO scale German four cylinder compound 4-6-2s which start off with eight chuffs per revolution and then automatically switch to four chuffs per revolution at a certain speed.  Unlike a Mallet compound or simple articulated the spacing of the chuffs doesn't change.

Stuart