Help with 'Speedy' valve gear and other issues...

[Roger]

Ok this has been annoying me for some time. The curved Brass washer on the vice jaw is used to provide something for the blast pipe to clamp down on to. It's the only thing holding the smokebox onto the saddle. The blast pipe is threaded into the fitting on the end of the 'Y' piece from the cylinders.

The problem is that given half a chance, the washer doesn't want to sit neatly following the curve of the smokebox, it would just as rather go wherever it pleases! Ok, it doesn't have to come off that often in service, but I seem to be taking it off a lot while I'm making it.

So here I'm adding a 2mm Stainless Steel location peg to stop it from rotating.


20181124_212017 by Roger Froud, on Flickr

The stepped plug on the vice jaw above is a close fit in the bore while the washer fits the inside to line it up for drilling through.

The packing is to stop the 4.8mm long peg from dropping through the second I strike the arc!

20181124_221246 by Roger Froud, on Flickr

I've left the end with sharp edges...

20181124_221301 by Roger Froud, on Flickr

... and added a tiny bit of 1mm Stainless filler rod. Thank goodness for the TIG welder, I guess this would have to be threaded and riveted over somehow otherwise.

20181124_222922 by Roger Froud, on Flickr

That was blended into the surface.

20181124_223338 by Roger Froud, on Flickr

It catches the edge nicely...


20181124_223910 by Roger Froud, on Flickr

... and screws down without any of its usual nonsense.

Ok, it's taken an hour and a half to do, but I'll enjoy taking it on and off now!

20181124_224003 by Roger Froud, on Flickr

[Roger]

This is how the banding is done on the firebox, there's an 'L' shaped bracket riveted to the band which is tightened by a piece of threaded rod and a couple of nuts.


IMG_1413 by Roger Froud, on Flickr

This is my interpretation of that. The scale diameter of the thread is 1mm, but that's not really man enough and it's too small to be practical. I've compromised by going a little over scale on the brackets to fit M1.4 studding.

20181125_153206 by Roger Froud, on Flickr



20181125_153247 by Roger Froud, on Flickr

This is the band that's held to the cladding with a single M1.4 screw on the side...

20181125_215015 by Roger Froud, on Flickr

... the bracket is secured by three 0.8mm diameter Steel rivets.

20181125_222417 by Roger Froud, on Flickr

The back of the band was slightly countersunk since these need to be flush when it's finished.

20181125_231956 by Roger Froud, on Flickr

I need to finish the other band, but this is how it will look. That's just a pencil line on the top to show me where the middle is.

20181125_232541 by Roger Froud, on Flickr

The four bands on the tapered barrel can have slightly more robust fittings. These are a bit wider and longer and one side is threaded. The idea is to use long M1.4 Stainless cap screws for those.


20181125_155019 by Roger Froud, on Flickr

I've just guillotined these, they look a mess...

20181125_162014 by Roger Froud, on Flickr

... but they clean up nicely.

20181125_201152 by Roger Froud, on Flickr

Folding them all together means they'll all be the same even if they don't bend exactly where I intended!

20181125_211948 by Roger Froud, on Flickr



20181125_212106 by Roger Froud, on Flickr

[Roger]

The band doesn't want to sit flat because it's a bit stiff. Here I'm using a piece of wire to help me form a small bend at that point...


20181126_185627 by Roger Froud, on Flickr

... but that still needs a little more work.

20181126_185905 by Roger Froud, on Flickr

The bands aren't quite flat enough for my liking  so I'll fiddle about a bit more with the bends. They aren't tight though, so they will sit down better when they are.

20181126_204654 by Roger Froud, on Flickr

IMG_1415 by Roger Froud, on Flickr

[Roger]

After much riveting and fiddling about, here is how the banding on the barrel looks.

20181127_210917 by Roger Froud, on Flickr

It all feels very rigid and there's no need for anything else to secure any of the cladding.

It makes me wonder why crinolines are considered necessary. I'm wondering if the reason is because Brass is very much less rigid than Steel?


20181127_210903 by Roger Froud, on Flickr

Completing this means I can now move on to sorting out what shape the back of the side tanks need to be.

[stevep]

Looking very impressive, Roger.

[Roger]

Thanks Steve.

I'm trying to sort out as many things as possible before splitting the frames to make the dozens of changes required to those. I really don't want to be adding holes at a later date unless it's absolutely necessary.

One of the things that probably need brackets are the two injectors. This is the RH side one...

DSCN5646 by Roger Froud, on Flickr

... and this is the LH side one. You'll notice that both water valves are on this side, presumably so the fireman can access them. The valves are bolted directly to the underside of the side tank.

The water for the RH side is piped forward of the firebox, then it dives under the boiler before returning next to the firebox where the RH injector is mounted. Obviously that's quite a long run of pipe, so it will have to be big.

Anyway, I'd like to model this arrangement because it's very visible and it would be nice to make the injectors look the part.

The problem is that the water is going to have to come from the side tank which isn't ideal. I've tried to dream up ways of getting water to the injectors from a driving truck which is what we use at the club, but without that Eureka moment. I could put a changeover valve inside the tank, but it would be inaccessible unless I make a removable panel under the tank which makes that possible. I won't rule that out just yet.

Another thought was to pipe water into the back of the pipes feeding the injectors and have separate water valves for those. I don't really like that either.

A thought that might just work is to feed water from the riding truck into a Tee piece on the inlet to the axle pump. The idea would be to have a stop valve and a non-return valve so that water can flow into the side tanks to form a level. The action of the axle pump would assist in drawing water from the driving truck, but that might work too well and end up overflowing the side tanks when the bypass valve is open.

I've tried to make those two valves into changeover ones that take water from the tank or from a pipe at the back, but I can't see a way to do that either at the moment.

From the tests that Doug performed, I'm wondering if it's possible to insulate the tank enough for warming not to be an issue. I also intend to use the design of injector with two valves that works with water at higher temperatures. If all of the water used comes from the side tanks, they ought to stay at a lower temperature since that will need replenishing fairly often either from the top or from the riding truck.

Maybe I'm missing an obvious solution, or perhaps someone can think of a cunning changeover valve arrangement that fits those two valves?

Lots of questions, and no clear cut answers yet.

DSCN5687 by Roger Froud, on Flickr

[barlowworks]

Hi Roger

Why not just have a change over valve on each feed to feed either via the tank or the riding truck. When you are running with the riding truck just don't bother with the water in the tanks and visa versa when running without the club riding truck. Also, this may sound daft but has anyone ever tried running with a few ice cubes in the side tanks to cool the water.

Mike

[Roger]

Nov 29, 2018 23:02:59 GMT barlowworks said:

Hi Roger

Why not just have a change over valve on each feed to feed either via the tank or the riding truck. When you are running with the riding truck just don't bother with the water in the tanks and visa versa when running without the club riding truck. Also, this may sound daft but has anyone ever tried running with a few ice cubes in the side tanks to cool the water.

Mike

Hi Mike,
That would be ideal, but it's difficult to physically do that because it's all on view. If those two valves could be changeover ones that would be great, I just don't see how to do it at the moment.

[David]

Nov 29, 2018 23:02:59 GMT barlowworks said:

Also, this may sound daft but has anyone ever tried running with a few ice cubes in the side tanks to cool the water.

This is common practice at our club on summer running days, although we put the ice in the tenders or riding truck tanks. I can't think of anyone who puts water in their side tanks here. I filled mine with sand for adhesive weight.

[Gary L]

Nov 29, 2018 17:35:42 GMT Roger said:

Thanks Steve.

I'm trying to sort out as many things as possible before splitting the frames to make the dozens of changes required to those. I really don't want to be adding holes at a later date unless it's absolutely necessary.

One of the things that probably need brackets are the two injectors. This is the RH side one...

[Snip]

... and this is the LH side one. You'll notice that both water valves are on this side, presumably so the fireman can access them. The valves are bolted directly to the underside of the side tank.

The water for the RH side is piped forward of the firebox, then it dives under the boiler before returning next to the firebox where the RH injector is mounted. Obviously that's quite a long run of pipe, so it will have to be big.

Anyway, I'd like to model this arrangement because it's very visible and it would be nice to make the injectors look the part.

No, you don't need brackets. You will have to disconnect the injectors quite regularly (for descaling, unblocking etc) and you don't want to make it any more difficult than it needs to be. Besides, the injectors won't need support, the pipework will be amply strong enough

Nov 29, 2018 17:35:42 GMT Roger said:

The problem is that the water is going to have to come from the side tank which isn't ideal. I've tried to dream up ways of getting water to the injectors from a driving truck which is what we use at the club, but without that Eureka moment. I could put a changeover valve inside the tank, but it would be inaccessible unless I make a removable panel under the tank which makes that possible. I won't rule that out just yet.

Another thought was to pipe water into the back of the pipes feeding the injectors and have separate water valves for those. I don't really like that either.

A thought that might just work is to feed water from the riding truck into a Tee piece on the inlet to the axle pump. The idea would be to have a stop valve and a non-return valve so that water can flow into the side tanks to form a level. The action of the axle pump would assist in drawing water from the driving truck, but that might work too well and end up overflowing the side tanks when the bypass valve is open.

I've tried to make those two valves into changeover ones that take water from the tank or from a pipe at the back, but I can't see a way to do that either at the moment.

From the tests that Doug performed, I'm wondering if it's possible to insulate the tank enough for warming not to be an issue. I also intend to use the design of injector with two valves that works with water at higher temperatures. If all of the water used comes from the side tanks, they ought to stay at a lower temperature since that will need replenishing fairly often either from the top or from the riding truck.

Maybe I'm missing an obvious solution, or perhaps someone can think of a cunning changeover valve arrangement that fits those two valves?

Lots of questions, and no clear cut answers yet.

[Snip]

A changeover valve is one way, but it isn't necessary and needs to be fitted into a crowded place. You need a shut off valve on the driving trolley, and one at the Pannier tank outlet, but beyond that you only need a discreet T-piece in the feed to the water valve for the injector(s) you intend to supply from the driving trolley. A simple rubber cap slips over the T-piece, which is replaced by a rubber pipe from the trolley when/if you use the trolley tank. The rubber cap can be just a short piece of black silicon rubber tube with one end blocked off. Being black it is very unobtrusive.

With the luxury of 2 injectors you may not feel the need to feed them both simultaneously from the trolley tank, and if they have a T-piece each you just swap over the feed tube if the need arises (because of a blockage, say).

With the standard Speedy, the Pannier tank capacity is not enormous, and being mounted close to the boiler they do tend to heat up, but if you draw from the tank injector first it shouldn't be too much of an issue. Insulation material might help a little, but there are limits.

On mine, I only drew from the panniers with the axle pump, where heating of the water was a positive benefit; which is more than can be said for the axle pump itself! The downsides of a pump are numerous: noise, rolling resistance, tendency to stick, unprototypical and general faff when driving, but this has all been discussed earlier on this thread IIRC, so I won't open that can of worms again! The biggest disadvantage I found was that on Speedy in particular, you need a really big balance pipe, which LBSC didn't draw. (If memory serves he didn't draw a balance pipe at all!). When taking the water from the balance pipe, which is the normal arrangement, with the bypass pipe feeding into just one tank, as normal, the result is coasting round the track with water cascading out of a tank filler. The balance pipe on Paddington is a much more businesslike (and prototypical) arrangement.

Hope this helps

Gary

[jma1009]

Hi Roger,

We are getting into the realms of miniature injector design. An ordinary good miniature injector will not feed if the water supply temperature exceeds 46 degrees C. A compromised (non optimum) designed injector will have a reduced operating range and may not pick up at lower temperatures of the water supply.

I have often mentioned on here that the simple remedy on a side (or in your case pannier) tank loco is to leave the injector water valve open all the time so that the tanks are frequently replenished. If via a mains stand pipe. I don't know what arrangement the East Grinstead club have for public running on their portable track, and presumably not mains supply as is common on permanent club tracks.

You mentioned "2 valves" as allowing the injector to work with a higher water supply temperature? Can you elaborate please?

As for a changeover valve, a pipe from the driving truck could be fed below the outlet of the water supply from the pannier tank and below the water injector valve proper. You simply close the pannier tank water valve to the injector in hot weather, and allow the water supply to come from the driving truck.

From my experience of driving side tank locos in miniature, I would say that only in hot weather you will encounter problems, especially if the static water supply is via containers that heat up in the sun as opposed to a cold water mains supply.

Cheers,

Julian

[Roger]

Nov 30, 2018 0:23:13 GMT Gary L said:

Nov 29, 2018 17:35:42 GMT Roger said:

Thanks Steve.

I'm trying to sort out as many things as possible before splitting the frames to make the dozens of changes required to those. I really don't want to be adding holes at a later date unless it's absolutely necessary.

One of the things that probably need brackets are the two injectors. This is the RH side one...

[Snip]

... and this is the LH side one. You'll notice that both water valves are on this side, presumably so the fireman can access them. The valves are bolted directly to the underside of the side tank.

The water for the RH side is piped forward of the firebox, then it dives under the boiler before returning next to the firebox where the RH injector is mounted. Obviously that's quite a long run of pipe, so it will have to be big.

Anyway, I'd like to model this arrangement because it's very visible and it would be nice to make the injectors look the part.

No, you don't need brackets. You will have to disconnect the injectors quite regularly (for descaling, unblocking etc) and you don't want to make it any more difficult than it needs to be. Besides, the injectors won't need support, the pipework will be amply strong enough

Nov 29, 2018 17:35:42 GMT Roger said:

The problem is that the water is going to have to come from the side tank which isn't ideal. I've tried to dream up ways of getting water to the injectors from a driving truck which is what we use at the club, but without that Eureka moment. I could put a changeover valve inside the tank, but it would be inaccessible unless I make a removable panel under the tank which makes that possible. I won't rule that out just yet.

Another thought was to pipe water into the back of the pipes feeding the injectors and have separate water valves for those. I don't really like that either.

A thought that might just work is to feed water from the riding truck into a Tee piece on the inlet to the axle pump. The idea would be to have a stop valve and a non-return valve so that water can flow into the side tanks to form a level. The action of the axle pump would assist in drawing water from the driving truck, but that might work too well and end up overflowing the side tanks when the bypass valve is open.

I've tried to make those two valves into changeover ones that take water from the tank or from a pipe at the back, but I can't see a way to do that either at the moment.

From the tests that Doug performed, I'm wondering if it's possible to insulate the tank enough for warming not to be an issue. I also intend to use the design of injector with two valves that works with water at higher temperatures. If all of the water used comes from the side tanks, they ought to stay at a lower temperature since that will need replenishing fairly often either from the top or from the riding truck.

Maybe I'm missing an obvious solution, or perhaps someone can think of a cunning changeover valve arrangement that fits those two valves?

Lots of questions, and no clear cut answers yet.

[Snip]

A changeover valve is one way, but it isn't necessary and needs to be fitted into a crowded place. You need a shut off valve on the driving trolley, and one at the Pannier tank outlet, but beyond that you only need a discreet T-piece in the feed to the water valve for the injector(s) you intend to supply from the driving trolley. A simple rubber cap slips over the T-piece, which is replaced by a rubber pipe from the trolley when/if you use the trolley tank. The rubber cap can be just a short piece of black silicon rubber tube with one end blocked off. Being black it is very unobtrusive.

With the luxury of 2 injectors you may not feel the need to feed them both simultaneously from the trolley tank, and if they have a T-piece each you just swap over the feed tube if the need arises (because of a blockage, say).

With the standard Speedy, the Pannier tank capacity is not enormous, and being mounted close to the boiler they do tend to heat up, but if you draw from the tank injector first it shouldn't be too much of an issue. Insulation material might help a little, but there are limits.

On mine, I only drew from the panniers with the axle pump, where heating of the water was a positive benefit; which is more than can be said for the axle pump itself! The downsides of a pump are numerous: noise, rolling resistance, tendency to stick, unprototypical and general faff when driving, but this has all been discussed earlier on this thread IIRC, so I won't open that can of worms again! The biggest disadvantage I found was that on Speedy in particular, you need a really big balance pipe, which LBSC didn't draw. (If memory serves he didn't draw a balance pipe at all!). When taking the water from the balance pipe, which is the normal arrangement, with the bypass pipe feeding into just one tank, as normal, the result is coasting round the track with water cascading out of a tank filler. The balance pipe on Paddington is a much more businesslike (and prototypical) arrangement.

Hope this helps

Gary

Hi Gary,
Ok, no brackets it is then. I'm not sure how the piping will be done, but it's unlikely to be as easy to dismantle compared to using commercial injectors. That's a whole new discussion though.

Feeding the backs of those feed pipes from the riding trolley might be the best solution, although I would prefer not to have more valves than necessary.

I presume that you don't have any insulation on the back of the side tanks? I get the impression that this is the usual situation, and it makes sense if you only ever use the axle pump from them. However, if you want to use the water for injectors, it makes good sense to insulate them. I don't think much thought has been given to side tank insulation, it seems to be accepted that they will just get hot!

I won't delve too much into the divisive subject of axle pumps except to say that 'tendency to stick' is a design flaw rather than something fundamentally wrong with the idea of a pump. Mine can't stick because the ball isn't left on the seat when the locomotive is laid up. If anything, I'd say there was less 'faffing' using an axle pump while driving, you can find a sweet spot where it pretty much takes care of itself with the occasional adjustment. Anyway, they're a useful addition in my opinion in some situations.

I'm not sure why the bypass outlet doesn't go straight back into the balance pipe? I don't see the necessity for it to exit into a tank. SPEEDY has a very large axle pump for some reason, I've reduced that considerably since with better Superheating it shouldn't be necessary.

You're absolutely right about there being no balance pipe on the SPEEDY drawings. I'm going to make a prototypical arrangement which ought to provide enough area.

[Roger]

Nov 30, 2018 1:03:34 GMT jma1009 said:

Hi Roger,

We are getting into the realms of miniature injector design. An ordinary good miniature injector will not feed if the water supply temperature exceeds 46 degrees C. A compromised (non optimum) designed injector will have a reduced operating range and may not pick up at lower temperatures of the water supply.

I have often mentioned on here that the simple remedy on a side (or in your case pannier) tank loco is to leave the injector water valve open all the time so that the tanks are frequently replenished. If via a mains stand pipe. I don't know what arrangement the East Grinstead club have for public running on their portable track, and presumably not mains supply as is common on permanent club tracks.

You mentioned "2 valves" as allowing the injector to work with a higher water supply temperature? Can you elaborate please?

As for a changeover valve, a pipe from the driving truck could be fed below the outlet of the water supply from the pannier tank and below the water injector valve proper. You simply close the pannier tank water valve to the injector in hot weather, and allow the water supply to come from the driving truck.

From my experience of driving side tank locos in miniature, I would say that only in hot weather you will encounter problems, especially if the static water supply is via containers that heat up in the sun as opposed to a cold water mains supply.

Cheers,

Julian

Hi Julian,
I'm really looking forward to dabbling into injector design, I think there's a lot of room for experimentation.

Yes, leaving the water flowing is something I've done on occasion, but usually I've not found it necessary on the club locomotives.

I'll chew over the options for feeding water from the riding truck, I suppose I could just feed one side, that would simplify matters.

With regard to the two valves on the injector, this mimics full size practice where air is prevented from being drawn in from the overflow by that large valve situated under the body. You can see it on the following picture where the large black pipe comes out of the bottom.

DSCN5646 by Roger Froud, on Flickr

This is one interpretation of that for a model sized injector. The top section contains a second ball that prevents air from being drawn into the gap between the mixing and delivery cones. It's done exactly the same way it's done for the other side ie the gap in the combining/mixing cones.

Hot water injector by Roger Froud, on Flickr

The claim is that this increases the allowable water inlet temperature. Presumably that's because the reduced pressure in that area helps keep the jet of water free of entrapped air.

[92220]

Roger that cladding looks amazing. I know what I have to aim for, though getting there might be a bit of a headache!!!! Perhaps I missed it. What thickness steel did you use for the cladding?


Bob

[Roger]

Nov 30, 2018 9:56:00 GMT 92220 said:

Roger that cladding looks amazing. I know what I have to aim for, though getting there might be a bit of a headache!!!! Perhaps I missed it. What thickness steel did you use for the cladding?


Bob

Glad you like it Bob. The Steel is 0.6mm thick nominally, so it's actually slightly under that. I think it's much easier to do it in Steel, Brass is so easily dented and scratched. The banding works well in Steel to.

[uuu]

Nov 30, 2018 9:03:18 GMT Roger said:

...I'm not sure why the bypass outlet doesn't go straight back into the balance pipe? I don't see the necessity for it to exit into a tank...

On some locos I've driven, the return into the tank is in a visible position, so the driver can see the overflow.

Wilf

[terrier060]

Having seen yours, I am going to do mine in steel now. Also the cab (even though I have bought the brass). In steel I can keep to scale thickness and no dents! Also takes paint better. Not sure about the tanks though. One way around keeping the injector water cool is to use the bunker as a water tank, or simply have a tank and coal bunker in front of you on the trolley. That is what we used to do in Soton. Great work Roger - I am almost looking forward to platework!!

[andyhigham]

My Sweet Pea with side tanks has no problem with injectors even in the midst of summer.
The tanks are flat sided next to the curve of the boiler with an air gap of 8mm at the narrowest point.
I usually leave the injector water running once set and have used tank water on all but the hottest days

[Gary L]

Nov 30, 2018 9:03:18 GMT Roger said:

Nov 30, 2018 0:23:13 GMT Gary L said:

No, you don't need brackets. You will have to disconnect the injectors quite regularly (for descaling, unblocking etc) and you don't want to make it any more difficult than it needs to be. Besides, the injectors won't need support, the pipework will be amply strong enough

A changeover valve is one way, but it isn't necessary and needs to be fitted into a crowded place. You need a shut off valve on the driving trolley, and one at the Pannier tank outlet, but beyond that you only need a discreet T-piece in the feed to the water valve for the injector(s) you intend to supply from the driving trolley. A simple rubber cap slips over the T-piece, which is replaced by a rubber pipe from the trolley when/if you use the trolley tank. The rubber cap can be just a short piece of black silicon rubber tube with one end blocked off. Being black it is very unobtrusive.

With the luxury of 2 injectors you may not feel the need to feed them both simultaneously from the trolley tank, and if they have a T-piece each you just swap over the feed tube if the need arises (because of a blockage, say).

With the standard Speedy, the Pannier tank capacity is not enormous, and being mounted close to the boiler they do tend to heat up, but if you draw from the tank injector first it shouldn't be too much of an issue. Insulation material might help a little, but there are limits.

On mine, I only drew from the panniers with the axle pump, where heating of the water was a positive benefit; which is more than can be said for the axle pump itself! The downsides of a pump are numerous: noise, rolling resistance, tendency to stick, unprototypical and general faff when driving, but this has all been discussed earlier on this thread IIRC, so I won't open that can of worms again! The biggest disadvantage I found was that on Speedy in particular, you need a really big balance pipe, which LBSC didn't draw. (If memory serves he didn't draw a balance pipe at all!). When taking the water from the balance pipe, which is the normal arrangement, with the bypass pipe feeding into just one tank, as normal, the result is coasting round the track with water cascading out of a tank filler. The balance pipe on Paddington is a much more businesslike (and prototypical) arrangement.

Hope this helps

Gary

Hi Gary,
Ok, no brackets it is then. I'm not sure how the piping will be done, but it's unlikely to be as easy to dismantle compared to using commercial injectors. That's a whole new discussion though.

Feeding the backs of those feed pipes from the riding trolley might be the best solution, although I would prefer not to have more valves than necessary.

I presume that you don't have any insulation on the back of the side tanks? I get the impression that this is the usual situation, and it makes sense if you only ever use the axle pump from them. However, if you want to use the water for injectors, it makes good sense to insulate them. I don't think much thought has been given to side tank insulation, it seems to be accepted that they will just get hot!

I won't delve too much into the divisive subject of axle pumps except to say that 'tendency to stick' is a design flaw rather than something fundamentally wrong with the idea of a pump. Mine can't stick because the ball isn't left on the seat when the locomotive is laid up. If anything, I'd say there was less 'faffing' using an axle pump while driving, you can find a sweet spot where it pretty much takes care of itself with the occasional adjustment. Anyway, they're a useful addition in my opinion in some situations.

I'm not sure why the bypass outlet doesn't go straight back into the balance pipe? I don't see the necessity for it to exit into a tank. SPEEDY has a very large axle pump for some reason, I've reduced that considerably since with better Superheating it shouldn't be necessary.

You're absolutely right about there being no balance pipe on the SPEEDY drawings. I'm going to make a prototypical arrangement which ought to provide enough area.

Hi Roger

Yes, I agree about the valves. The T-piece plus bung does away with a valve and needs no maintenance. At a pinch you could do away with valves on the exit from the pannier tanks as well, and rely on the injector water valves. However I think you referred earlier to the possibility of backfilling (or at least levelling) the pannier tanks from the trolley tank, and with a shut-off valve at the tank you can completely prevent that. It isn't a major crime, but using the shutoff prevents you running out of both sources of water at the same time.

An argument against trying to insulate the pannier tanks is that there is generally water swishing around (from overflows when filling, not to mention rain!) and a many common insulators don't work well when wet. Also, when it takes 4"+ of insulation to keep our homes cosy, the skimpy amounts we can fit on locos are working against the odds. LBSC left a generous air gap, but of course it isn't enough.

WRT the bypass outlet, I never thought of that! Though on my Speedy (long gone incidentally) I don't recall there being enough room between the pump and the balance pipe to work in a T-connector, but I could be mis-remembering. However Wilf is quite right, the idea of discharge into the tanks was so that you could see the overflow and judge if the pump was working (or, even more important, if the water has run out!). But to benefit from that, you have to run with the tank filler open, which not everyone likes.

Best regards

Gary

[Roger]

Nov 30, 2018 19:10:33 GMT terrier060 said:

Having seen yours, I am going to do mine in steel now. Also the cab (even though I have bought the brass). In steel I can keep to scale thickness and no dents! Also takes paint better. Not sure about the tanks though. One way around keeping the injector water cool is to use the bunker as a water tank, or simply have a tank and coal bunker in front of you on the trolley. That is what we used to do in Soton. Great work Roger - I am almost looking forward to platework!!

Hi Ed,
I don't think you'll regret that decision. Having done the engraved plate for yours, the plate work should be easy.

I'm erring towards using the tanks as the source for the injectors since that's the way it's done on 1501. However, to do that, I need to not only insulate the tanks well, but also arrange for water to be drawn from the riding truck. I think the axle pump is the key to this puzzle, but it will almost certainly be necessary to be able to see the levels in the side tanks. I could make a 3-way valve on the inlet to the axle pump to draw water from the side tank and/or the riding truck. That way, the water is always returned to the side tank which means it ought to be possible to set the 3-way valve to keep the side tank level broadly the same. Obviously it's possible to end up pumping into the tanks until they overflow, but that's not a catastrophe, just embarrassing!

Having water always being taken from the side tanks is going to keep them cooler than just leaving them full and only using them with the axle pump.