Stuart ‘Victoria’ : a beginners tale..

[Chris BarryParticipant @chrisbarry]

Allan,

loving the thread, I've started a Rob Roy but some of the techniques you've asked and shown has answered lots of questions for me, may I say thank you for that

looks smashing, can't wait to see it finished, keep it coming

many thanks

Chris

[GarryCParticipant @garryc]

Hi Chris

Thanks very much, glad you are enjoying it. Is that a new Loco build you are starting, it would be great, really very interesting to see progress of that bit by bit. I don't know whats involved in building a Locomotive and would love to see the work involved… If you are only just starting we could see it start to finish – can I twist your arm? It only takes a couple of minutes to upload a few photos and words as you go along and I'm sure you will likely find as I am that you will learn more from others commenting and helping on here…

Good luck with it all…

Cheers.

Allan.

[GarryCParticipant @garryc]

Assembly 7.

Another couple more photos and details of Assembly progress.

Have everything connected up now except the levers to the Valve Rod. It all seems to move smoothly enough. Have been oiling here and there to ease things, the oil cups which I had thought might just be a bit for show are really useful, maybe even essential really to get the oil where it needs to go, I'm glad I put them in now as they were an 'add on option' in the build plan.

Assembly so far 1.

Assembly so far 2.

Assembly so far 3.

Next the levers to the Valve Rod and then to look at how to do the Valve Timing.

Regards.

Allan.

Edited By Allan. on 25/02/2014 12:54:31

[Mike BondarczukParticipant @mikebondarczuk27171]

Allan,

An absolute cracker so far. Looking forward to seeing the next phase and your start to a new project.

Many thanks,

Mike

[GarryCParticipant @garryc]

Thanks Mike.

Assembly 8.

The Valve Rod Levers made and fitted – in the same way as previous ones, starting to find this a bit easier to do now although the end result still needs a long way to go. Need to find out how to do the Valve Timing next …. All seems to be ok and moving smoothly so far..

This is probably not the right place to ask but in case there are any 'historians' with an interest on here, and reading this, can anyone tell me if this general type of engine (low pressure horizontal) could have been found in late 19C Woollen Mills in the UK – specifically Devon and Cornwall area?

The Valve Rod Levers in place.

Ready to do the Valve Timing next..

Regards.

Allan.

[Steve WithnellParticipant @stevewithnell34426]

The Stuart Victoria is based upon a workshop engine found in a workshop in Bristol. The cylinder was 10 inch x 5 inches. The history is in Andrew Smith's book "Building the Victoria – A 19th Century Steam Engine".

I chose the Victoria for my build, because it matched (with simple mods) a Lancashire mill engine configuration I wanted to copy, so the configuration of the slide valve on top of the cylinder is not uncommon.

Steve

[GarryCParticipant @garryc]

Hi Steve

The likely, or not, connection with Mills is just what I was after so thanks very much for that…

Cheers.

Allan

[Chris BarryParticipant @chrisbarry]

Allan,

I'll get the current bit on the horn guides done and will start the thread

Looks really close to running now, I look forward to the video

Cheers

Chris

[GarryCParticipant @garryc]

Sounds good Chris, look forward to seeing it.

Seems like we will have both your new Locomotive and Dan's Traction Engine build to follow from the start soon (4" Foster beginner's build thread) – couldn't be better!

Cheers

Allan.

[GarryCParticipant @garryc]

Going to have a look at how to do the Valve Timing, hopefully later this afternoon or weekend and have ordered some brass piping and unions to connect to the engine. Meantime I'm thinking about what air pump / compressor I would need to give it a try on air. Stuart specs say that 60 psi is the 'Working Pressure' of the Victoria and I was wondering if something like an airbrush compressor would be suitable. e.g. this one is advertised as having its working pressure as 0-4 bar, about 58 psi I think **LINK** and not too expensive.

I haven't decided for sure yet but am thinking about and looking at the Stuart No 1 as my second project, that is if it's suitable for beginner level (I'm not quite sure it is at the moment) and will help in continuing the learning curve on from Victoria. The specs also say 60 psi working pressure for this engine and so it makes sense to be able to use the compressor for this as well – until I get a boiler…

Any advice on which pump or specs to go for would be much appreciated – as cheaply as possible of course..

Thanks.

Cheers.

Allan.

Edited By Allan. on 28/02/2014 12:13:49

[JasonBModerator @jasonb]

You should be able to run a far less than 60psi if it's just for display, My Stuart beam which has the same size cylinder will happily tick over at 10psi. But you do need a decent volume as the tanks can soon get depleted.

Although the small diaphram compressor you show may state about  1cfm that will not be for long, you need to look at the FAD value which is Free Air Delivery eg what the pump can put out continuously rather than what will come out of the full tank.

Take a look at Machine Mart or the likes of Aldi and Lidl who often have small compressors at reasonable cost, something with a 1.5-2HP motor and 25Lts plus tank. 5 to 6 cfm minimum. The advantage with these is you can also use them in te workshop and also to run an airbrush or small spray gun.

And for a bit of incentive have a look at this scratch built No1, link to lots of construction photos at the bottom of page.

J

 

Edited By JasonB on 28/02/2014 12:35:04

[Steve WithnellParticipant @stevewithnell34426]

Forgot to mention, I asked Stuart Models a while back what the flywheel speed should be for the Victoria. They said 100 – 200rpm. Mine is set up for 150rpm. I posted a vid on YT and got "feedback" that I was running it far too fast!

Could you be tempted to add the governor?

Steve

[Steve WithnellParticipant @stevewithnell34426]

Hi Allan, if it's mill engines that you are interested in, here is a model of a mill engine. The model must have been made around 1905. For scale the spokes in the flywheel are pocket watch winders…

I found I could easily copy the configuration using the Victoria kit and Victoria spares, but not of course the intricacy. This is a model of the Lancashire mill engine I referred to early, but I've not been able track down the specific mill. (I still need to add the railings to mine…I wonder if these models are ever completly finished )

The lubricator is sat on top of the steam chest and is called a "shapely lady".   One old timer told me that getting the sequence of opening and closing the taps wrong was very exciting.

 

Some other photo's of this in my Victoria album.

Steve

Edited By Steve Withnell on 28/02/2014 14:39:45

[GarryCParticipant @garryc]

Hi Jason

Thanks very much, thats really useful and stopped me getting the wrong thing… The Photos of the Stuart No 1 look superb I'm pretty certain that's what I will have a go at…

Hi Steve.

Haven't looked into the governor yet – I'm still wondering if its going to run as it is now to be honest. Now I've gotten around to thinking about the valve timing its only just occurred to me that has it doesn't have any gears how is the direction of rotation set or known each time – I'm missing something somewhere…

The mill engine is incredible, the skill it took to do that amazing especially with the tools of the time… I can see the underlying similarity to Victoria. My great great grandmother toiled away in a woollen mill no doubt in terrible conditions in the mid / late 19th Century…

Cheers.

Allan.

[JasonBModerator @jasonb]

You can set the direction by which way the valve leads the crank and then it will only run in one direction. It is possible to set the valve with no lead which allows the engine to run either way but you may find it a bit lumpy.

J

[julian atkinsParticipant @julianatkins58923]

hi jason,

i think you have forgotten the lap on the valve which together with any lead sets the angle of advance of the eccentric and so there would be no way of having both directions of rotation on the above design.

cheers,

julian

[GarryCParticipant @garryc]

Hi Jason and Julian

Julian's post has prompted me to try and find out a little more about this as I know nothing at the moment!

This off wikipedia has at least given me some idea now..

When on the move, a steam locomotive requires steam to enter the piston at a controlled rate.[3] This entails controlling the admission and exhaustion of steam to and from the cylinders.[3] Steam enters and leaves the valve through a steam port, usually at the middle position of the piston valve.[3] Where the valve is in contact with the steam ports, a consideration of the "lap" and "lead" is required.

Lap[edit]

The "Lap" is the amount by which the valve overlaps each steam port at the middle position of each valve.[3] However, there are two different types of "Lap."

The first kind is the "steam lap," which is the amount by which the valve overlaps the port on the live steam side of the cylinder.[3] Secondly, there is the "exhaust lap," which is the amount by which the valve overlaps the port on the exhaust side of the cylinder. "Exhaust lap" is generally given to slow-running locomotives.[3] This is because it allows the steam to remain in the cylinder for the longest possible amount of time before being expended as exhaust, therefore increasing efficiency.[3] shunter locomotives tended to be equipped with this addition.

The "Negative exhaust lap", also commonly termed "exhaust clearance," is the amount the port is open to exhaust when the valve is in mid-position, and this is used on many fast-running locomotives to give a free exhaust.[3] The amount seldom exceeds 1/16 in. when exhaust clearance is given; the cylinder on both sides of the piston is open to exhaust at the same time when the valve is passing through the mid-position, which is only momentary when running.[3]

Lead[edit]

The "lead" of the valve is the amount by which the steam port is open when the piston is static at front or back dead centre.[3] Pre-admission of steam fills the clearance space between the cylinder and piston and ensures maximum cylinder pressure at the commencement of the stroke.[3] "Lead" is particularly necessary on locomotives designed for high speeds, under which conditions the valve events are taking place in rapid succession.[3]

All very interesting I thought.

Cheers

Allan

Edited By Allan. on 28/02/2014 19:00:34

Edited By Allan. on 28/02/2014 19:03:21

Edited By Allan. on 28/02/2014 19:20:38

[julian atkinsParticipant @julianatkins58923]

hi allan,

yes, its a fascinating subject and IMHO one of the aspects of the steam loco both fullsize and miniature that makes it so absorbing! ive 3 locos that i designed the stephensons gear myself in pre computer days with the help of Don Ashton's excellent booklet. ive another 2 locos where Don Ashton very kindly redesigned the gear for me personally using his simulator.

in general terms 'lap' is the amount by which the valve is wider than the port width. i would very interested to know what the port width and 'lap' is on your stationary engine.

in miniature both Don and i prefer to think of 'lead' not as a measurement but as the angle in degrees that the valve opens the port to steam ahead of the dead centres (dead centres – the exact end/start of the piston's stroke).

there is another factor called 'cut off' not mentioned in your list which is a product of the amount of 'lap'

i dont have much experience of slow running stationary engines apart from making a Stuart 10 many years ago, so what is appropriate for a slow rotating stationary engine will be quite different to a steam locomotive.

cheers,

julian

[JasonBModerator @jasonb]

Julian with the lap set equal on both ends of the valve and the eccentric at 90 deg to the crank you can make them run each way, lumpily and inefficiently as I said but they will run

[GarryCParticipant @garryc]

Hi Julian

I'm not exactly sure I'm understanding correctly but would I be right in saying that the 'Lap' on the Victoria is 11.9mm? Thats with a port width of 3/32" and valve width of 9/16". Or by Port Width do you mean the width across all three ports…..? Drawings below..

The Port Face Drawing.

The Sliding Valve and Valve Rod Drawing.

The Sliding Valve in place on the engine.

Regards.

Allan.

Edited By Allan. on 28/02/2014 20:51:30

[JasonBModerator @jasonb]

Lap on the stuarts is 3/64."

Take the total of the 3 ports and the two bits between which equal 9/16 away from the total length of the valve which is 21/32 gives 3/32 and divide by 2 to get the lap = 3/64"

Edited By JasonB on 28/02/2014 20:53:17

Edited By JasonB on 28/02/2014 20:54:31

[Anonymous]

Allan: I think you might need to turn the slide valve through 90°?

Regards,

Andrew

[GarryCParticipant @garryc]

Ah thanks Jason. I was just changing the post above in case that was the case…

Great learnt something again! 

and now with the drawing you have added makes it much clearer, I didn't realise the importance of the recess under the valve – think I have it now!

Cheers.

Allan.

Edited By Allan. on 28/02/2014 20:58:40

Edited By Allan. on 28/02/2014 21:01:55

[GarryCParticipant @garryc]

Hi Andrew

Yes looks like you are right  looking at the drawing again and now with Jason's drawing as well I see the light!…

Cheers.

Allan.

Edited By Allan. on 28/02/2014 21:00:43

[julian atkinsParticipant @julianatkins58923]

yes, lap is 3/64"s which is 1/2 port width. on a loco you would expect lap to be 3/4 if not more x port width. there is no 'exhaust clearance' on your design which im pleased to see.

i dont think you will require more than a few thou 'lead and dead centres.

cheers,

julian

[Author]

Posts