Tunnel steam plumes!

DGE-Railroad

DGE-Railroad

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Has anyone considered doing this in G scale?

O gauge tunnel steam plumes

An ingeniously simple concept; a fog machine triggered by a loco entering the tunnel dumps a brief quantity of fog towards the top of the tunnel, near the exit.

The air pressure of the exiting train gives a pretty realistic effect. Live steamers obviouisly have a bit of a headstart in this area, but I think it would be pretty effective for both live steam and electric.

I plan on introducing a tunnel to the layout design and trying it :)
 
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PhilP

PhilP

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For outside?

Keeping something like this maintained, and it's integrity, in a British climate? - For what? several times a year's use??

A small 'pond fogger' device, maybe. But a pukka smoke machine? :wondering:


Possibly a good idea for an exhibition / indoor layout, but not for outside. - Unless the unit is demountable for storage..

YMMV, of course.
PhilP.
 
DGE-Railroad

DGE-Railroad

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My concern was the outdoor installation too. I think the fog machine would need to be removable and just wheeled out for running. That's certainly the way Geoff (whose layout that is in the video, uses his). I do have a machine already but I certainly wouldn't fancy keeping it outside as a permanent fixture.

Somebody else suggested a pond fogger - I had to Google it as I wasn't familiar with them. Although they're more weatherproof, I'm not convinced agitating water to create a mist for spraying over locos, rolling stock and track is going to be the ideal solution... :/
 
dunnyrail

dunnyrail

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I think a pond fogger may be just the thing. Dig a small pond in the tunnel with girders and chicken mesh over the top I reckon would work a treat with a never ending trail of steam exiting the tunnel made more so when a train exits.
 
DGE-Railroad

DGE-Railroad

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I think a pond fogger may be just the thing. Dig a small pond in the tunnel with girders and chicken mesh over the top I reckon would work a treat with a never ending trail of steam exiting the tunnel made more so when a train exits.
I'll keep an open mind about the fogger idea; if certainly has several pluses (you could even have a small rain catcher to help replenish the water source!), but isn't the output going to be VERY moist? Can anyone who has one chime in? :)

Perhaps its worth picking up a cheapy and having a play. .
 
P

Paul M

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Isn't the smoky bit from a vaping cigarette worth a try?
 
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DGE-Railroad

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That's a good thought Paul. Nice and compact, battery powered (a big plus, as it'd be a fair way from the house)
It'd just be a case of wiring in a trigger circuit in place of the button or whatever they have :)
 
Paul2727

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I made a mini battery powered smoke device for the resin dragon that sat by the pond. Ran off a 9v battery via a movement sensor, so it blew smoke when people walked past. Unfortunately It's all packed away at the moment, but the link below give a simple explanation of how to do it.
 
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-bbbb

-bbbb

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You could redirect your laundry dryer exhaust into the tunnel upon the train triggering a relay of some sort inside the tunnel.
You'd need to be doing laundry on a cold day while operating the train, but the effect might be like this:
 
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dunnyrail

dunnyrail

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Very interesting set of solutions, like the vape thing. This has all sorts of possibilities. Would probably need to be mounted in a building with a method of firing up using track contacts to set of and shut off (rather than the push button) whilst the train is in the tunnel. 15 seconds would be more than adequate one imagines.
 
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DGE-Railroad

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Yes, I think the vape solution is winning for me at the moment. It appeals on the grounds of size, cheapness and power source.

Because my track is unpowered and some of my locos have insulated axles, I'd probably opt for an IR trigger.

The interface between the detection module and the vape device would probably be something like this

20201018_075311.jpg


This £6 circuit will trigger an output after an input is detected. The triggered output is programmable for duration, delay and retriggering delay in increments of 0.1s.
The whole thing can then run off a battery.

I don't know anything about vape devices so have been reading up. There are plenty of videos demonstrating how to turn them into mini fog machines, as Paul highlighted.
It would seem 'cloud chasing" devices might be best as they're geared towards large plumes of smoke. The board output would replace the button push for the vape device and a little air pump.

The end result should be a brief delivery of smoke near the top of the tunnel after the train is first detected. It can be remotely mounted (probably under the track boarding my case) to make refilling/removing/recharging easy
 
dunnyrail

dunnyrail

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Your triger could be a choice of a few things, a small micro switch mounted on the rail so the wheels push the arm down to make a connection would work nicely and be cheep as chips.
 
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Paul2727

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Your triger could be a choice of a few things, a small micro switch mounted on the rail so the wheels push the arm down to make a connection would work nicely and be cheep as chips.
Also matching the air blower to the amount of smoke the smoke unit produces is quite key. I tried 3 different sizes / power of blower until I found one that gave the effect I wanted. It's also worth checking just how much noise the air pump makes.
 
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DGE-Railroad

DGE-Railroad

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Many thanks Paul. Yes, they were both things concerning me - most of the videos I found either had US specific or out of date links so I think there's going to be an element of luck or trial and error.
Would you mind sharing which smoke unit and blower you ended up deciding on for the dragon?
 
Paul2727

Paul2727

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Sorry, most of the parts were scrounged up or from car boot sales, so no idea of make or models. Also I wanted more of a jet of smoke than a general fog, which I assume would be more realist for what you'd need for a tunnel.
Incidentally how much larger is the bore of your tunnel than the trains. I ask this as the smaller the gap, the larger the piston effect of the train passing through it would be. (Think about the rush of air that proceeds the passage of a tube train.)
If it's quite tight you could inject a jet of smoke and let the train push it out. If its larger, then you'll probably need to have the smoke outlet close to the exit and pointing in that direction.
I'm afraid it will be very much trial and error to get the effect you want. Old 12v PC case fans make for reasonable air movers if suitably boxed and ported.
Regards,
Paul.
 
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Northsider

Northsider

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Put some Bisto in the vape juice and you could replicate the Welwyn Tunnel fire of 1866. Two trains had crashed, when a third carrying meat to Smithfield Market joined them. According to LTC Rolt "all that night and all through the next day the ventilation shaft belched flames, smoke and the smell of roasting meat over the surrounding countryside."
 
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