Sirius: Alco "Firefly" version

[redhouseluv]

Having just completed the Sun engine I thought it would be a good time to look at its big brother, the Sirius; I bought this at an auction some time ago where it sat amongst a lot of Hornby trains and other locos.

Its a Sirius, but was connected to the Alco generator sets in WWII (see below for complete set). There is an excellent website for those interested in the history https://alcofirefly.com/

As you can see someone has gone a bit crazy with the paint scheme which is funny as it was designed for covert operations 

Jobs to do:

- get it running
- make an exhaust
- replace the missing pressure gauge
- remove the draincock at the end of manifold and then put it back to its original location
- finally return it to its more somber army green colour

As usual I haven't got the taps and dies I need and am puzzling over the thread sizes. Also back to having soldering issues which I still haven't cracked......I'll post some pics

[Roger B]

Looks a fun project   

I once had a chance to play with the successor to this, the Mk814:

https://www.stationroadsteam.com/mk814-steam-generating-set-stock-code-1995/

It had a single cylinder engine and a boiler like a motorbike cylinder.

Jack Hampshire had a Sirius to drive a dynamo for the lights on his Foden Steam Wagon 

[redhouseluv]

That's a big piece of kit; I like the boiler is has a great shape

[Jasonb]

Depending on age you may have some small Whitworth threads as well as 26tpi

[redhouseluv]

Threads

Ah okay, small Whitworth threads .... are they less than 26 or bigger i.e more or less threads per inch?

From the current Sirius drawings the exhaust is 1/2" x 26 and the inlet 3/8" x 26 (neither of which I have, but have ordered). The manifold however has a cap which can be removed and looks like it has been designed to take a brass nipple (see pics).

I have tried the 1/2" x 20, 1/2" x 13, but it looks a lot 'courser' than the exhaust 1/2" x 26, so I have no idea what it can be as none of my thread gauges fit?

Solder

This is my collection of soldering stuff; none of which I have manged to have any success with other than the yellow tub with the electrical solder on it which I have used to temporarily solder bearing brasses. All I want to do is solder brass fixtures to copper pipe; I have watched numerous videos all of which make it look simple, but I end up with flux which doesn't run, but burns or solder which doesn't melt. If someone can tell me which flux with which solder that would be a good start?

In desperation, I used soft solder to fix a nipple to a 1/4" pipe and was thinking about drilling through the cap to make the union for the manifold?

Any help with threads or soldering correctly greatly appreciated, thanks

[Jasonb]

I would say your thread is 1/4" BSP. British Standard Pipe threads are measured by the bore of the pipe so the size bears little relation to the overall diamater but is generally about 1/4 "larger. 1/4 BSP has an OD of 0.518" and is 19tpi.

The smaller whitworth sizes can be quite fine and were used before BA became the more common thread

For silver soldering I would be using the temnacity No5 mixed with a little water into a paste and then one of your silver (yellowish) solder rods. Th eN05 is a hight temp flux and will stay active for longer than easyflow flux.

The yellow tub will go with teh coil of electrical solder which is more than likely flux cored.

You should not need much more than those two.

Available heat is a factor that can affect the ability to silver solder parts, if you can't get enough heat into th epart in a reasonable time then even the No5 can get exhausted

[uuu]

I only use Tenacity No5 flux on stainless steel or other difficult materials.  I've found EasyFlo is fine for Copper and brass, even large assemblies.  But you need enough heat to get things done without hanging round for ever.  A 7Kw burner is quite a good all-rounder - although you need a lot more for a boiler, say.  The Sievert Crafstman set goes up to 86Kw!  Only used once - set fire to the garage.

You need something to clean off the fitting after soldering.  For EasyFlo, citric acid is a favourite - it's a lot safer than the sulphuric acid that used to be suggested..  Tenacity can need a caustic solution to shift it.

Wilf

[crueby]

Be careful not to mix soft (low temperature) and hard (high temperature) solder. The name 'silver solder' gets used for both sometimes in the hobby industry - there is some sold as 'silver solder' that is just soft solder with a tiny amount of silver mixed in. The high temperature silver solders have a range of 40% or more silver in them, and require the matching high temp fluxes, like the Tenacity 5 or Harris Black. The high temp hard solder should never be used on something that has low temp soft solder on it - they dont play well together. The high temp flux will start to melt and flow close to the temperature of the silver solder, and where the metal is starting to glow a bit. As the others said, if the torch is not up to the task of heating it all within a couple minutes, the flux will burn off and just leave a black mess that has to be cleaned off before trying again. Great thing to test on practice bits of scrap first to get the hang of it!

[redhouseluv]

The Sievert Crafstman set goes up to 86Kw!  Only used once - set fire to the garage.

That sounds dangerous and if I survived that my wife would probably kill me 

Okay at least I know of what goes with what - I'm currently using one of these, is that the problem, not the right tool for the job?

I'm just digesting BSP being based upon the bore size, that's a completley new one on me. Finally I hope I ordered the correct item for the 1/2" x 26TPI its description was given as BSB BSCY,CEI 26 TPI TAP DIE SET 1/2" TAP AND DIE set?

[crueby]

Small torches like that are fine for small fittings, but as parts get larger it will fall short pretty quickly. As a test, take a piece of brass about the size you want to solder and run the torch on it for a minute or two - if the brass is not getting up to at least a dull red heat in that time, its not enough to do the job well. For larger/heavier parts, most of us use a larger torch that runs off a propane tank like on a gas grill. I like the Seivert line of torch handles/nozzles, though there are other brands out there just like them. A few fireplace liner bricks make a great platform to put the parts on for soldering, they reflect some of the heat while protecting the surface they are on - outdoors is best! And beware of the heat/flame blowing past your parts/bricks, ensure there is nothing (like a garage wall/ceiling) too close...

[uuu]

Outside is good - but in gloomy or indoor conditions, it's easier to see the glow that the hot parts are giving off.  Ventilation is good - and a necessity if using cadmium-bearing solders (these are banned in the UK now, but I have a small supply of the older stuff).

Wilf

Edit - brass can melt if you get it too hot.  Copper can too, but that needs a much higher temperature - so the garage is already on fire at that point.  I'm a fan of having the solder on the joint whilst heating - away from the point of max heat - which is drawn towards the heat when it melts - so it liquifies when things are hot enough and you don't need to overdo things.

[redhouseluv]

Thank you for the advice, I've seen a few examples for sale on our favourite auction site, what nozzle size should I be looking at the type of small work I'll be using it for?

[Jasonb]

A burner around 7 to 8kw will do for most things and I rarely change to anything else. If you go with Sievert then that is a No2941 burner which is 28mm diameter but down to 25mm will be OK. Ideally a 4bar regulator but 2bar will do at a push

I'm the opposite and tend to feed in the stick once the flux flows rather than place bits of solder on the joint unless I have a few odd bits to use up.

[redhouseluv]

Perfect, I'll add that to the Christmas list

I'm looking forward to getting to grips with soldering, its something which I have have repeatedly failed at and need to be able to do

[uuu]

An advantage of the Sievert (or similar) bottle/regulator/hose/handle/nozzle approach to heating is that for very little extra outlay you can fit a bigger or smaller nozzle for other jobs.  As noted, the 7/8Kw is excellent, and can do most things.  I'm also a fan of the "cyclone" style of nozzle, which admits the air back at the handle end, so can work in more confined spaces, like inside a locomotive firebox.

As with all these engineering things, practice and making mistakes (I'm good at that) is the key to progress.

Wilf