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I had fouled up the FEF by running her low on water and overheated the boiler. Ryan took care of that and this video is result of his fine work.
As I said earlier, my days of videoing while running the big engines is over ,except stionary cameras. Too much to look after and too much money envolved for that pleasure.
Thanks to Ryan, all is well.
I thought evening video is great. The video was done by Charles.

BTW, noise in background, are Cicados.
 

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Art;

Steam and cicadas, what a delightful combination. The cicadas are starting to die off in the Roanoke area (too much sex - what a way to go!), but the crickets and katydids are in full voice.

Thanks for sharing.

Cheers,
David Meashey
 

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Art, (or Ryan or Charles) what exactly happened to your FEF? Did you add water to an already overheated boiler? What needed repair?

We try to never get into that situation but schturff happens. (I know what happens when you add water to an overheated K4 boiler, so I'm extremely careful w/ mine!)
 

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Discussion Starter #4
Art, (or Ryan or Charles) what exactly happened to your FEF? Did you add water to an already overheated boiler? What needed repair?

We try to never get into that situation but schturff happens. (I know what happens when you add water to an overheated K4 boiler, so I'm extremely careful w/ mine!)
Dave
Mybe Ryan will look at this thread and comment.
It all started when I was not paying attention to the FEF while running at Zube Par. I got distracted by doing video and talking to guest who were asking questions and the "Beast" was drinking more water than I provided. Got way to hot, and instead of just shutting her down I added water to hot boiler.
What damage, Ryan will have to explain. Whatever it was, and apparently it was reparable, because TRS did their job. Replaced "O" rings,Gaskets< and oteher things that have a tendency to fry when gotten to hot.
As you can tell from video, she is fine now.
BTW, this all happened on my second run of the day and run of the FEF. I just did not pay enough ateention to water reserve. Gonna have and Aux tender next time and no camera
Thanks Ryan and Charles
 

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Moral to the story (the short version): If it runs out of water, put the fire out and let it cool!

As Art said, the boiler got way too hot. Adding water to an already overheated boiler is a huge issue in itself and can cause all sorts of bad things to happen.

In this case the rear tube sheet and the nest of 12 flues got hot enough to cause the braze to start to liquefy around the lower flues. Until a few years ago I (and others) never would have thought it possible to get enough BTU out of an alcohol wick burner to make silver braze go into a liquidus state. However with the fan on and the large wick area of the FEF it is possible in the right conditions!

When water was pumped in the boiler it immediately flashed to steam and this then exploited the weakened braze joints. In turn this caused quite a few leaks to develop on the rear flue sheet, mostly centered around the lower half of the flue nest.

An additional problem caused by the overheating was the disintegration of all the seals on the fittings and pipes. The boiler got hot enough to vaporize the silicone o-rings used for the throttle and blower spindles and all boiler fittings were suspect to similar stresses. The sudden pressure increase of the boiler [caused by the flashover when water was pumped] in resulted in two of the auxiliary banjo bolts that feed the ancillaries to crack at the cross hole.

This and the flue sheet leaks made for massive parasitic steam losses and as a result the engine could not hold or generate anything above 30 psi as most went direct to atmosphere.

All of this is repairable and it is a situation that can happen to anybody. Attentiveness to the engine at all times is paramount and predicting what will happen within the next few minutes is key.

The good rule of thumb is that if the engine stops quickly after running well, or the pressure suddenly plummets, stop, get the fire out and let it cool! Putting a fan on to "save" the fire or paint or ties is a discouraged practice.

Never add water to a boiler that has been run dry and/or overheated.

Besides the risk of failed braze joints, the sudden pressure increase can cause the annealed copper to give in and distort. Remember these parts are designed to be surrounded with water at all times and do not take subjection to shock well when overheated.

This distortion or "failure" is commonly realized as a collapsed flue or sagged/warped crown sheet. These heat concentrated areas are generally well softened and easily distorted with a sudden thermal shock (plus massive pressure influx) of cold water flashing to steam on a red hot annealed copper surface.
 

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See here:

Making a Banjo Fitting

More photos here:
Banjo 1
Banjo 2
Banjo 3
Banjo 4

As you can see the bolt has a variety of uses. The first photo is a fairly traditional banjo bolt. The second and third show the bolt being used to prodive a feed to a blowdown valve that bolts onto the lower sight glass fitting in photo 4

Your Ruby uses a banjo bolt to secure the throttle manifold to the boiler, the manifold is in essence a Banjo fitting.

The name comes from the look of the fitting when assembled. The round bushing and then the pipe coming off of it emulate the shape of a Banjo.
 

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See here:

Making a Banjo Fitting

More photos here:
Banjo 1
Banjo 2
Banjo 3
Banjo 4

As you can see the bolt has a variety of uses. The first photo is a fairly traditional banjo bolt. The second and third show the bolt being used to prodive a feed to a blowdown valve that bolts onto the lower sight glass fitting in photo 4

Your Ruby uses a banjo bolt to secure the throttle manifold to the boiler, the manifold is in essence a Banjo fitting.

The name comes from the look of the fitting when assembled. The round bushing and then the pipe coming off of it emulate the shape of a Banjo.
thanks ryan for the explanation.:)
 

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Moral to the story (the short version): If it runs out of water, put the fire out and let it cool!

The good rule of thumb is that if the engine stops quickly after running well, or the pressure suddenly plummets, stop, get the fire out and let it cool! Putting a fan on to "save" the fire or paint or ties is a discouraged practice.

Never add water to a boiler that has been run dry and/or overheated.
Ryan,
Whilst I agree with what you have said, I think that not to scare people we need to be clear here.
If you are running an alcohol fired loco and the boiler runs out of water and therefor stops quite quickly, it has been my experience that it IS okay to immediately add water, as at that point since the draft has ceased the flame is soft and will not add significant heat.
The added water will then normally turn into steam so that the blower is again functional and you can continue to slowly bring up the water level, and even add the suction fan at that time.
As you say, it is NOT okay to add a suction fan with an empty boiler, causing the flames to give off full heat and then not add water for a significant amount of time.
As to how long a time, I am not sure, but I assume that we are talking many minutes before adding water to cause the catastrophic damage that has been explained here.
Perhaps the issue here is that for the larger locos, the wicks have become dangerously large in order to produce enough heat?
All the best,
David Leech, Delta, Canada
 

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David,

It has nothing to do with the size of the engine, but how the situation is handled.

By your logic then, across the board is it; OK to add water to a gas fired engine that is run dry? How about if the engine is coal fired?

Although we don't have the risk of critical crack length development in copper boilers (which makes things go boom), do you really want to instill the practice of getting away with it as being acceptable? I certainly do not. Complacency will develop and as a result it becomes standard practice to constantly stress items to failure, which is completely unnecessary and bad practice, period.

It is like running a automobile engine up past redline and saying it is OK to get away with it. Sure you can probably do it 100 times without issue, but what about 101 times? Every time the probability of a failure increases, even if you know the calculated risk and how to handle it, there is always a wild card factor that can make for an all around bad day.

I have seen smaller alcohol fired engines suffer similar problems under these circumstances. Yes, the larger burner areas can make more heat, but not without assistance. No matter how you cut it, running out of water is bad and correct practice dictates the heat source be extinguished to avoid damage to the boiler.

The line is so very thin between "getting away with it" and risking damage to paint, seals and/or boiler that it is not better better to err on the side of caution?

Of course the obvious thing to take out of this is don't run it out of water, period. It is not as if these boilers are so small that a safe water level cannot be maintained at all times of operation.
 

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Ryan,
When there is no draft, an alcohol fire is weak.
When there is no draft, a gas fire is still full power.
When there is no draft a coal fire is still very hot.
NOT the same - different logic.
But we do agree - NEVER RUN OUT OF WATER!
Regards,
David Leech, Delta, Canada
 

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David,

I see the point, but you are expecting that everyone can see the same, experts and amateurs alike. What is to stop the layperson from taking the logic for alcohol as universal and applying it to gas or coal firing?

There will likely be an instinct to put the fan on to prevent the flame hunting about while putting water back in. Not withstanding the fact that the thermal stresses you are putting on the boiler are still the same regardless of the fuel source, the fan makes all the logic the same as the alcohol fire is again concentrated heat.

Not everyone has the same mindset and the situational pressures can vary. This alone makes it a bad idea to apply differing logic to similar situations which can result in differing outcomes.

Again, best to err on the side of caution and extinguish the heat source as quickly and safely as possible without subjecting the boiler to any unnecessary stresses.
 

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can you extinguish a alchohol fire as quickly/ easily as a butane one?
also, what type of alchohol do thes things burn? denatured alchohol? rubbing alchohol? beer:rolleyes:?
 

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Discussion Starter #16
can you extinguish a alchohol fire as quickly/ easily as a butane one?
also, what type of alchohol do thes things burn? denatured alchohol? rubbing alchohol? beer:rolleyes:?
Nate
Most of the guys here use denatured alcohol. Smells horrible but it works.
As to how you put out fire? I sometimes shut off alcohol before she finishes her run and let the fire die down that way. May open a con of worms, but have avoided blowing out the wicks with the c0/2
cartridges.
As this thread has made quite clear. Never put water into an overheated boiler. That is when I would use co.2 when the flame needed to be extinqushed pronto.

I would by starting a thread about the FEF would open somes eyes to the way you can destroy a beautiful engine. As most of you know, I am 81 years old and still learning howw to run live steam.
 

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darn, would be great if the things used beer as fuel:rolleyes:. i agree that we should NEVER EVER EVER NEVER NEVER EVER NEVER let our boilers run dry.
I agree with your conclusion of the dry boiler, but like I said earlier in this thread "schturff happens"!
 

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Yes - but one of the reasons that "schturff happens" is that people tend to ignor the water gauge because so many of these gauges are completely inadequate.

One well known maufacturer even quote in their own operating manual for their locomotive .... "The accuracy of the water gauge glass may be affected by air bubbles and capillary action."

On my model the accuracy had been affected to the point that it's often completely unreadable, so I took it apart to see what the problem was. A number of issues became apparent - the most significant being that the internal passages of the gauge piping are too small for a gauge glass bore of 2.76mm.

For example, the cross bore of the banjo bolt - which IMHO is unsuitable for this application anyway - was only 1.00mm .... :eek:
 

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When I first started in live steam, my first loco had no water gauge.
You learned how long it would run on a filling of alcohol.
Then I fitted a tender pump.
You learned that after lighting up you would add water until a gentle back and forth of the loco would blow water out of the blower so you knew when the boiler was getting full.
You learned that when you added fuel to remember to add some water.
You would learn as to how long to run before stopping and pumping in more water.
I guess what I am saying is DO NOT JUST RELY ON WATER GAUGES, learn what you loco does.
Understand what it needs and pay attention to it.
I am afraid that I have seen people who think that they are just like electric locos and you can turn a knob and ignore them.
They are not.
They are like living things that need your attention to avoid problems.
All the best,
David Leech, Delta, Canada
 
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