...

Main problem, scent does not scale.  It goes everywhere.

Can it ever be replicated?

Sure, creosote your benchwork and fertilize your stock cars, etc.  

@ctxmf74

The replication of Creosote would be nice but not the real stuff as an agent we'd want to huff for Medical reasons.

@Benny

Agreed. You'd need a Museum sized layout to *maybe* pull it off. Just putting it out there.

Scents : do-able

Dear OSCR,

There are various ways to do scents, right now.

- Mega-Steam do some scents, which are generated by smoke crackers.

http://megasteam.com/page2.html

Bearing in mind it's entirely possible to "drive" a suitable Seuthe smoke gen via a DCC decoder, this is one way of doing "DCC Scent"

- "Controllable" scent-generators are available, which use synthetic "aroma essences". The generators use either chemical reaction, water, or heat to "activate" the essence fluid, and then usually use a calibrated fan-forced system to control the "ammount" of scent, and the "cloud"/"dispersal.

Indeed, such systems have been used in commercial cinema situations, usually controlled by a sub-tone control track in the Dolby encoding.

Avatar in Korea
http://collider.com/avatar-goes-4d-in-korea/

Ads in Germany and UK
http://adage.com/article/news/smell-movie-theater-ad/129864/

Japan attempts
http://www.filmcomment.com/article/wake-up-and-smell-the-new-world
/> (NB this is the same country who are now broadcasting 22.2 3D audio free to the general public)

KoolFog
http://www.koolfog.com/scenting-delivery-system/applications/

The key to the success (or failure) of such systems is usually not the scent itself, but the delivery system.
Thinking "we'll just pump scent thru the A/C system" is prone to failure for it's "scattergun" approach.

In model RR terms, we generally have the benefit of:
- an enclosed space
- which is controlable in terms of draft, temp, and humidity
- and can accurately deploy fractions-of-a-milligram of scent essence where and when required.

It's do-able, if you really want to...

Happy Modelling,
Aim to Improve,
Prof Klyzlr

PS use of Proscenium-style benchwork is immensely helpful in controlling both scent and sound SFX. The almost-fully-enclosed environment controls the diffusion and spread of the effect, nd greatly reduces the unwanted external effects.

PPS have witnessed very effective deployments of creosote'd ties, a single drop of the real (original) creosote kept a HO show-layout worth of tie-piles "smelling fresh and new" for over 9 months.

PPPS pungent smells tend to work best, or at least give the most "Oh poo, what's that smell?" effect for the least ammount of material and effort...
("Eau de stockyard" anyone?) 

PPPPS as with Scale Sound, 
where the actual dB SPL delivery volume is critically lower than most modellers realise, 
the key to eliminating "unwanted scent drift" and keep things in "scale perspective" is to use far less of the scent-generating essence, and deploy it very very locally...
(If the viewer has to lean-in to the scene to "smell the roses", then you can be sure you have "scale roses"... ).

Scented smoke oil

I know that there are scented oils for use in smoke generators.  While I'm not a big fan of smoking model locomotives, perhaps those oils could be used (sparingly) to achieve the effect you're thinking of?

hmmm ...

... just getting my head around sound ... now you've added another thing to the bucket list ...  

Agree with the Professor, it should be "doable", just need to set your mind to it and work out the best solutions.

Olfactory Airs

Years ago (1970s or 80s)  in this grand hobby there was a product line called Olfactory Airs that tried this.  If I remember right is had 'smells' for things like roundhouses, creosote, various industrial applications, barn yards, forests and the like.  It used a small sponge and drops of some liquid applied to the sponge for the smell. There was no fan or heating element (I think) involved so it must of relied on air currents to disperse the odor.  Some of the smells were just plain nasty.  Needless to say it didn't stay around on the market.   .........  Rick

Scratch-n-sniff

Better idea

I was thinking ...

... a pine forest would be a 'no brainer' ... plenty of pine scented stuff about.  I do like the brewery though ... really I do!  

Detection

Perhaps proximity detection could be employed as a means of controlling the scent dispersal?

David Stewart

More on Olfactory Airs

Hey, I remember those well.  They were produced in the mid 80s.  The biggest problem that I recall was that most of the scents only vaguely smelled of what they were supposed to be.  Some didn't resemble their namesake at all.  I recall experimenting using cotton balls for the "receptor" (a few drops on the cotton ball) and placing them in hidden places.  Visitors found It hard to determine exactly what they were smelling.  The odor didn't last long either....not nearly long enough for an entire operating session.

Then one day Olfactory Airs was gone.

If I were to use scents today, I'd probably want creosote, pine (for the forests) and perhaps some coal smoke or diesel exhaust.  Of course, they would have to be very subtle.

Olfactory Airs

I remember them. The main problem is that scents could not be kept separate, They kind of  blended together.

I never tried them, but I heard a few people say it made their layouts stink. Olfactory Airs were not around for very long. They turned out to be a major flop.

Beer and Pies!

This takes me back to my first few years as a young drivers assistant(British Rail) we used to spend a lot of time in the town of Burton on Trent, as this was where we fueled and examined locos. Burton was the home of 4 different breweries as well as a meat pie factory add to this the Marmite factory (used the yeast) and on certain days the smell of brewing and meat pies cooking filled the town! It was a busy railway town as well, 3 steam sheds plus numerous industrial lines to the various breweries. It was said there were well over 300 level crossings in the town.

Oh, the smells of childhood!

A a child growing up in St. Matthews, KY about 15 miles East of downtown Louisville as the crow flies I can remember clearly the smells when the wind blew from West to East.  You see, downtown Louisville at the time (1950's & 60's) had (4) breweries, (3) distilleries, and a huge stockyard.  The air often spelled like beer, sour mash, and cattle %%$$!

Pine

Dear Dave O,

For those modellers using pine layout framing, they theoretically should have it automatically?

For those wishing to consciously give the effect:
- a timer-dispenser "pine" air freshener will puff out a measured burst every 5, 10, or 20 minutes
- for those concerned about liquid residue, a small timer-powered fan blowing past a "pine" car air freshener or similar would give a controllable residue-free result

Happy Modelling,
Aim to Improve,
Prof Klyzlr

Proximity detection

Dear Dave S,

"People detection" options are available, inc the RTR solution from Pricom. http://www.pricom.com/Trains/MotionSensor.shtml

Tag with their PNET system, and DCC drive/decoders, and full layout/proximity/time-of-day effects are entirely do-able...

Happy Modelling,
Aim to Improve,
Prof Klyzlr

Creosote, Diesel, and "Subtle"

Dear Jack,

Check in with MegaSteam, they have the scents you are acking for...

t'ain't nuttin' subtle about the pungent stench of creosote...
(Subtle in "localisation", sure.
However, if it's subtle in terms of "delicate on the olefactory palette", 
then it ain't creosote... ).

Happy Modelling,
Aim to Improve,
Prof Klyzlr

Smells blend together : ex Olefactory Aire

Dear NS,

Sounds (pun not intended) just like some "objectionable" LayoutSound deployments,
in the sense that it's not the effect itself, but a poor (excessive, uncontrolled) depoloyment of said effect that's ruining it overall.

When it comes to sound, and presumably scents, it is entirely possible to have it "too loud/much/pungent"

Assuming "the few people" you canvassed were using the O-A "moo poo", "creosote", and other "objectionable" type scents O-A specialised in, then would this not suggest that they actually were a success?
(In the same way that a well weathered car looks "dirty",
and the Warehouse Rave Party on "Brooklyn:3AM" feels "noisy",
a stockyard which "stinks" would seem to be entirely appropriate... ).

Happy Modelling,
Aim to Improve,
Prof Klyzlr

Smells of childhood...

Dear Alco, Rick,

There is a CSX switching area just East of Mansfield on the NEC known as "the Chocolate". It received this name because of a nearby chocolate factory (which was not rail served IIRC),
which occasionally covered the area with a vapour cloud of "chocolate scent" when in full-production.

It occurs that a layout modelling this area could well do with a chocolate variant of a "fondue heater", or a "chocolate fountain", to emulate the localised namesake scent... 

Happy Modelling,
Aim to Improve,
Prof Klyzlr

Scents on the Layout

There was a n-scale module in Florida that featured a stockyard that had a crock pot underneath the yard filled with moo poo and water cooking away. It was removed after a few shows. The moo poo scent was too strong.

"It occurs that a layout

"It occurs that a layout modelling this area could well do with a chocolate variant of a "fondue heater", or a "chocolate fountain", to emulate the localised namesake scent..."

   and a hot bun inside the bread factory?  

I Said, Prof Said

The professor obviously isn't the other guy!