Amazing chuff

[Moonraker]

I came across an American device called a "Bark Box" which is the first chuff device I have heard which sounds like the real thing and not a model. Far better than a chuff pipe. You can see it at http://www.trainsales.com/barkbox.htm .

Does anyone know if they can be made to fit into a Roundhouse smokebox?

Peter

 

[bobg]

From their website it sounds good, and from the dimension requirements seems quite a complicated device.

I have no experience of these things, or chuff pipes, other than what I've heard on the likes of Youtube, where they seem to sound quite good. Having experienced drafting problems on larger locos, my fear is, will it adversely affect the steaming properties to fit something like this. I'm tempted to fit something to my Countess but..........!!!

 

[brianthesnail96]

Not cheap are they... I'd have to hear one in a smaller loco (Ruby etc) before I'd be convinced by it- I would expect a decent chuff from a loco with cylinders that size, but it might be a different story with a (relatively) small RH or Accucraft UK loco. I also think it would be tricky to fit to a roundhouse loco without restricting the flow of hot flue gasses. Must admit I'd be interested to hear what Chris (Mr Summerlands Chuffer) thinks of these, I know he has done a lot of research (and testing!) to ensure that the Summerlands chuffers don't stifle performance.

 

[New Haven Neil]

From what I have seen of Bark Boxes, there is little chance of getting them to fit in a smaller model such as a Roundhouse. They use a resonance chamber in the smokebox that is bigger than a Lady Anne smokebox on it's own ! These K's are BIG engines. It's all about size....er....:thinking:

edit. The concept is much the same as a summerlands chuffer as far as I can see, except instead of using the smokebox as a resonator as Chris has, a separate chamber (the box) is used. As Matt points out, filling the smokebox will restrict gas flow from the flue, whereas the US engines are big enough to have the box mostly ahead of the chimney, leaving more free area for gas flow. Shame, really, theyare good, with a gruffer sound, but it really is about size.....

Thinks........I wonder if a remote resonator chamber like a Bangham whistle would work.....????

 

[400Parker]

There's a review of the Barkbox in the latest (June) Garden Railways magazine on page 96. There's a picture of it fitted to an Accucraft C16 and it fills the smokebox, but the http://www.trainsales.com/barkbox.htm < Link To vendor does sell a Barkbox for a Ruby / MiMi /Ida/ Forney which are smaller locos. They're not cheap - $100 to $125 - so the Summerlands Chuffer is excellent value in comparison. There's a You Tube video of the Barkbox at http://www.youtube.com/watch?v=QzXN7QjHIi0
Steve

 

[New Haven Neil]

Interesting, Steve - I'd like to see how they have done it, and especially to hear one in a Ruby or clone - I suspect it won't sound too much different to a Summerlands as the volume is similar, but I am prepared to be proved wrong!

 

[Sea Lion]

Whilst I am a Summerlands chuff pipe fan this Barkbox looks worthy of investigation for Accucraft UK and Roundhouse models.

Of course being a Baldwin the Accucraft Uk L&B Lyn has some smokebox volume forward of the chimney....

I guess the only way we are going to find out is to set up a working party to "experiment", either it will be able to be made to work or it won't!

Happy steamings,

John

 

[MRail]

will it adversely affect the steaming properties to fit something like this. I'm tempted to fit something to my Countess but..........!!!

Bob,
A friend of mine fitted a Summerlands chuff pipe to his Caradoc, and found the loco's steaming deteriorated, seeming "choked".
He also did not like the sound. Since it was past the money-back time limit, he passed the pipe on to me.
Fitted to my Edrig, it performs quite well, although there is a slight sensation of restriction.

I have since fitted Mike Ousby's Acme version to my Wrekin and Lawley, and they both perform well.
The sound seems slightly softer than the Summerlands.

Rob G

 

[bobg]

Thanks for that Rob, perhaps after that I'll leave alone, at least until it's run in and I have a feel for how it should be. I must say though that I do like to hear a good chuff , makes a loco sound like it's really working.

 

[brianthesnail96]

Very happy with the Summerlands chuffer on my Edrig. If it does restrict it slightly it's only going to be at the expense of flat out speed which you'll never use, and in fact it will probably give you more control over the locomotive at low speeds. Might affect outright hauling power but I've never seen an Accucraft loco fail to haul a train through lack of power (given plenty of steam, engine in good order etc), they nearly always break traction first.

I like the noise too...

 

[bobg]

Thanks again Matt, I will still probably wait till I've seen how it performs, but that is encouraging. Low speed controllability will be important on my line, as will full power. I will have a 1:40 ruling grade.

Hope the Marina is behaving.

 

[brianthesnail96]

Bob- let me have your address- I'll post you mine so you can do some testing and decide for yourself. My loco is going to be out of service for a least a fortnight, not least 'cos the entire burner system is in Plymouth whereas the engine is in Gloucestershire!

Edit- assuming you have an Accucraft loco of course. Not sure it'll fit your avatar (which is a class I don't recognise- I'm right in saying it's not a Sweet Pea yes?).

 

[bobg]

The whole intention when I built it was to confuse the onlookers. It's based on Romulus, with bits of this and that.

My track, whilst partially built, will not be ready for a few weeks yet for it's inaugural run. Thinking about blogging it on here soon.

PM to follow shortly, I'm about to watch the one-way system in Monte Carlo.

 

[Chris Bird]

Sorry I'm late into this one - I am away from my computer and have only just borrowed a laptop.

When I started developing the Chuffer, the Bark Box was the "Holy Grail" and is a very clever device indeed. I have never seen or heard one in the flesh - only in photos and videos - but it was clear to me that fitting one to Roundhouse locos would be either impossible or a major engineering exercise. Essentially it seems that you need to get the front of the smokebox off to do it - and then find room, convert it to twin pipe (on many types) and also deal with the drafting issues. I should be fascinated to see it done though ........

As Neil said, I aimed to achieve a similar effect using the natural resonance of the smokebox and that is why we have so many versions which are tuned to the loco. In fact the Chuffer (with a couple of exceptions) is the same - it is the positioning that changes to suit the loco.

Most Accucraft locos - from Edrig up to the mighty K-27 and K-28 have the same 3mm screw fitting for the Accucraft exhaust which does give a little restriction. The Chuffer has essentially the same sized hole in the adapter and in the chuffer and so does not increase this restriction in any way.

An Edrig would fit in the tender of a K-28 and these huge locos do not have a problem with restriction and can haul massive loads - admittedly at higher boiler pressure. The Edrig is also the same power unit as Caradoc, Wrekin, Ragleth, Mortime, Lawley etc. and none of these are resticted by the Chuffer. Of course the loco sounds like it is working harder at given throttle opening ......because that is the whole idea!

What is very clear though is that the sound varies between locos. I was recently told that the sound of an R/C Edrig improved significantly when a servo was added to the regulator rather than just using the reverser. The chuff can be a bit squishy with the latter I am told. There are also mods detailed on the website which can have an effect.

I think that Nigel and I have exactly the same approach as the Bark Box guys - we are only interested in having happy customers who are able to enjoy a good chuff! So please do let me know if you have any concerns. And you are welcome to be the first to send one back if you don't like it!!
Cheers
Chris

 

[bobg]

Hi Chris,

Glad to see you're still using that photo that I put on the front cover of the 'News' for you.

 

[Chris Bird]

Ah ha! So your'e that Bob!

It was an honour indeed to have the front cover of the 7 1/4 News!

It is still one of my favourite photos (my avatar) - though I spend much more time with the smaller locos these days.......
Cheers
Chris

 

[bobg]

Yes! I've recently moved up to this scale as there's no suitable track for miles round here. Now I can have my own.

 

[Chris Bird]

Bob - when I got home, I checked a couple of Accucraft exhausts - and as I thought, one was 1.35mm and one 1.4mm ID at the threaded fitting. The Chuffers are a minimum of 1.4mm at both thread and jet so they cannot increase the back pressure.

To prove the point JohnStJim sent me a video last night of his virtually new, hardly run Accucraft Earl hauling a serious load up a 1:75 (and possibly 1:45 near the summit) curve at the Flatland Washes Railway on Sunday. No shortage of power there I think!

You can see and hear it here: http://www.youtube.com/watch?v=upih5Ym1LHM&sns=em < Link To http://www.youtube.com/wa...upih5Ym1LHM&sns=em

Thanks JSJ

Cheers
Chris

 

[bobg]

Flaming Nora! That's a load! I (will) have a ruling grade of 1:40 here. but I haven't room in the passing loops for a train as long as that (I haven't that much stock yet anyway). Once I've run it in I will seriously consider fitting one.

Thanks Chris.