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JimH

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  1. Like
    JimH got a reaction from AdgeCutler in It is just so Super (Sentinel).   
    So where do you start? The same place as last time. Get the spare parts book and start scoring things off.
     

    This is the page for the rear axle. All you need is one (or two) of everything and you are home and dry. The well of spare parts is pretty much dry so you are on your own. Almost everything will need to be made. Fortunately one bit which would be very difficult to make is the injector. Through dumb luck we managed to get one.
     

     
    The injector uses steam at boiler pressure to force water into the boiler (I have no idea how). Normally the engine driven water pump does that but if you are stationary then you need an injector. How injectors work is pretty much a black art as far as I can see. The other bits in the picture are the raw castings for the windscreen hinges.
     

     
    Exciting, huh? These are two raw castings for the water tank filter boxes. Each one will soak up many hours' of machine time. Another part we got early was a chimney base. The exhaust from the engine exits up the chimney to provide induced draft on the fire. Don't worry, there will be some recognisable bits along soonish.
     

     
    Also quite early we managed to get a casting for a steering box. Here is the box in the boring machine.
     

     
    The throttle valve partially machined and bolted to the boiler shell.
     

     
    A boiler non return valve in its raw state.
     

     
    And this is another part of the throttle valve. It's called the dump valve and it makes a "Phsssssttttt" noise when you use it. The idea is that because the throttle opens and closes by hand you have a foot pedal which dumps the steam straight up the chimney away from the engine. This is handy for moving around slowly but also it is your OMG emergency brake. According to the operator's manual when things are grim you step on the dump valve, drag the engine into reverse and let go of the dump valve. The handbok describes this as "To stop almost instantaneously at risk of snashing the engine".
     

     
    This is the feed heater. The exhaust steam passes through this box as the boiler feedwater is fed through a coil inside. This improves efficiency.
     

     
    Things start to look a little more finished than others. Here is the crank arm for the steering box.
     

     
    And here is a more finished steering box and cover.
     

     
    Front and rear towing eyes. Some nice chap had a pattern made for one and we cadged the pattern to make our own.
     

     
    A new boiler top with chimney base fitted. Hole in the middle is the coal hole. It looks trivial but the boiler top was a weekend's work.
     

     
    The feedheater box machined and ready for its cladding.
     

     
    New lathes are shite. This is our middle lathe. I love Swifts. They are no Dean Smith and Grace but they're not bad at all.
     

     
    So, what you have seen is a tiny snippet of six months' of effort. What you may have noticed is no mention of an engine. This was something that had been exercising us since the start. Building everything else was not that big a deal but making an engine from scratch was going to be a big ask for reasons that will become obvious. We also needed an engine to give us a waggon number an a proper registration.
     
    Stay tuned for the next thrilling episode which can wait until tomorrow.
     
     
     
     
  2. Like
    JimH got a reaction from BlankFrank in It is just so Super (Sentinel).   
    At close to the turn of the last century the Glasgow firm of Alley and Maclennan moved to Shrewsbury and changed their name to Sentinel. They developed a steam cart that became known as the Standard and because it was so much better than most of what had gone before they sold a shed load of them and made a lot of money. However, by the early 1920s the Standard was old hat and had a number of design issues (trival matters like no brakes to speak of were becoming more important as roads got busier and loads got heavier). Sentinel put their thinking caps on to design something new and then went bust. The company was kicked back into life with a name that was only slightly different put their thinking caps back on and came up with the next model. It had features that were super. Its engine was super, the cab was super and it even had a foot brake which were super. There could only be one name for a waggon (two Gs because Sentinel couldn't spell either) that was this super and that is what we are discussing here. 
     
    The Super deserved its name because despite a number of odd design features it was pretty much the sweet spot. A decent cab and brakes but without the problems of the later models.  I've posted this one a couple of times already but I can't be bothered uploading another example of a Super - they all look about the same. This is a Super Sentinel with a coke body on it.
     

     
    For the uninitiated the general idea is the boiler sits right at the front in the cab and is fired from the top. The bunker is in the cab too. You then have the twin cylinder engine slung under the chassis with a chain driving each rear wheel. Steam waggons are bad for all sorts of reasons which is why lorries have pretty much always run on diesel. They do have a few advantages. They are quiet, they produce more torque than you have heard of and they don't have gears. Open the throttle and go. They are a joy to drive on the road. Particularly in traffic.
     
    And here's the one we built back in the early 1990s. What I mean by "built" should become apparent as we go on.
     

     
    You will note a few key differences. This one has windscreens. This was a period option and are essential. It also has pnematics rather than solids. Many waggons were returned to the factory to be converted from solids to pneumatics which allowed them to run at a legal maximum of 20mph instead of 12mph. We drive our waggons on the road so solids are a non-starter. You will also see that this one is very short. Some were cut down to drawbar tractors in period, however, in our case the shortness of the wheelbase was forced on us because where it lived at the time we couldn't get anything longer into the shed.
     
    It was finished in 1995 and we did about 3500 miles in it - the above photo was taken about 130 miles from home. We got bored of it in 2000 and sold it to a chap who did about 12,000 miles in it. The old girl is living down south somewhere now. We moved onto the restoration of the later S Type Sentinel (photo elsewhere) and a couple of years ago we decided that we would build another Super because they are bestest.
     
    This time round we will build it longer because the ultra short wheelbase of the last one wasn't brilliant on the road. Think SWB Series III Land Rover with tired springs and you'll know where I am coming from. So what we are aiming for this time round is something with the wheelbase and body of the Charringtons one up there with the windscreens and pneumatics of the one below it. Oh, and steam brakes and electric lights which are all period options/factory modifications.
     
    There is a bit to catch up on so it will take a few posts. If it gets too dull let me know and I will stop.
     
    Oh, and I am crap at taking pictures.
  3. Like
    JimH got a reaction from spartacus in It is just so Super (Sentinel).   
    So where do you start? The same place as last time. Get the spare parts book and start scoring things off.
     

    This is the page for the rear axle. All you need is one (or two) of everything and you are home and dry. The well of spare parts is pretty much dry so you are on your own. Almost everything will need to be made. Fortunately one bit which would be very difficult to make is the injector. Through dumb luck we managed to get one.
     

     
    The injector uses steam at boiler pressure to force water into the boiler (I have no idea how). Normally the engine driven water pump does that but if you are stationary then you need an injector. How injectors work is pretty much a black art as far as I can see. The other bits in the picture are the raw castings for the windscreen hinges.
     

     
    Exciting, huh? These are two raw castings for the water tank filter boxes. Each one will soak up many hours' of machine time. Another part we got early was a chimney base. The exhaust from the engine exits up the chimney to provide induced draft on the fire. Don't worry, there will be some recognisable bits along soonish.
     

     
    Also quite early we managed to get a casting for a steering box. Here is the box in the boring machine.
     

     
    The throttle valve partially machined and bolted to the boiler shell.
     

     
    A boiler non return valve in its raw state.
     

     
    And this is another part of the throttle valve. It's called the dump valve and it makes a "Phsssssttttt" noise when you use it. The idea is that because the throttle opens and closes by hand you have a foot pedal which dumps the steam straight up the chimney away from the engine. This is handy for moving around slowly but also it is your OMG emergency brake. According to the operator's manual when things are grim you step on the dump valve, drag the engine into reverse and let go of the dump valve. The handbok describes this as "To stop almost instantaneously at risk of snashing the engine".
     

     
    This is the feed heater. The exhaust steam passes through this box as the boiler feedwater is fed through a coil inside. This improves efficiency.
     

     
    Things start to look a little more finished than others. Here is the crank arm for the steering box.
     

     
    And here is a more finished steering box and cover.
     

     
    Front and rear towing eyes. Some nice chap had a pattern made for one and we cadged the pattern to make our own.
     

     
    A new boiler top with chimney base fitted. Hole in the middle is the coal hole. It looks trivial but the boiler top was a weekend's work.
     

     
    The feedheater box machined and ready for its cladding.
     

     
    New lathes are shite. This is our middle lathe. I love Swifts. They are no Dean Smith and Grace but they're not bad at all.
     

     
    So, what you have seen is a tiny snippet of six months' of effort. What you may have noticed is no mention of an engine. This was something that had been exercising us since the start. Building everything else was not that big a deal but making an engine from scratch was going to be a big ask for reasons that will become obvious. We also needed an engine to give us a waggon number an a proper registration.
     
    Stay tuned for the next thrilling episode which can wait until tomorrow.
     
     
     
     
  4. Like
    JimH got a reaction from HillmanImp in It is just so Super (Sentinel).   
    One of the things that made the decision to build another Super easy was that we had a boiler lying around. We designed and built the boiler for the first one, then built a new one for the S Type and then built another three of them. However, for reasons that don't need to be gone into we didn't sell the last one and kept it back. Here is the the last one we built sitting in a support frame. A pressure vessel designed, constructed and documented to the Pressure Equipment Directive. This is not your usual try to claim that it is a repair effort and the design dossier is what might be called extensive.
     
    The grates are at the bottom and you drop coal down the top. It is a water tube design which is a copy of Sentinel's own design. It is what is referred to as a spiral pattern firebox. See below.
     

     
    Here is a firebox that we made for the S Type prior to the tubes being welded into the firebox. The are sixty 1" OD tubes. This is double the number that Sentinel used. The problem of this design is that machining the tube holes is a little tricky because they pierce the firebox at a crazy angle.
     

     
    The pattern the tubes make is rather hypnotic. The reason for this layout is that it gives a high heating area but it lets you have a hole in the middle. This is very important because that is what the coal falls through.
     

     
     
    What we also had lying around was a new superheater which was meant to go with the boiler. The superheater sits inside the combustion space and heats the steam to above saturation temperature. Higher temperature = higher efficiency. Note 944 being ignored.
     

     
    So that is what we started with. A new boiler and a new superheater that were lying round doing nothing.
  5. Like
    JimH got a reaction from warch in It is just so Super (Sentinel).   
    At close to the turn of the last century the Glasgow firm of Alley and Maclennan moved to Shrewsbury and changed their name to Sentinel. They developed a steam cart that became known as the Standard and because it was so much better than most of what had gone before they sold a shed load of them and made a lot of money. However, by the early 1920s the Standard was old hat and had a number of design issues (trival matters like no brakes to speak of were becoming more important as roads got busier and loads got heavier). Sentinel put their thinking caps on to design something new and then went bust. The company was kicked back into life with a name that was only slightly different put their thinking caps back on and came up with the next model. It had features that were super. Its engine was super, the cab was super and it even had a foot brake which were super. There could only be one name for a waggon (two Gs because Sentinel couldn't spell either) that was this super and that is what we are discussing here. 
     
    The Super deserved its name because despite a number of odd design features it was pretty much the sweet spot. A decent cab and brakes but without the problems of the later models.  I've posted this one a couple of times already but I can't be bothered uploading another example of a Super - they all look about the same. This is a Super Sentinel with a coke body on it.
     

     
    For the uninitiated the general idea is the boiler sits right at the front in the cab and is fired from the top. The bunker is in the cab too. You then have the twin cylinder engine slung under the chassis with a chain driving each rear wheel. Steam waggons are bad for all sorts of reasons which is why lorries have pretty much always run on diesel. They do have a few advantages. They are quiet, they produce more torque than you have heard of and they don't have gears. Open the throttle and go. They are a joy to drive on the road. Particularly in traffic.
     
    And here's the one we built back in the early 1990s. What I mean by "built" should become apparent as we go on.
     

     
    You will note a few key differences. This one has windscreens. This was a period option and are essential. It also has pnematics rather than solids. Many waggons were returned to the factory to be converted from solids to pneumatics which allowed them to run at a legal maximum of 20mph instead of 12mph. We drive our waggons on the road so solids are a non-starter. You will also see that this one is very short. Some were cut down to drawbar tractors in period, however, in our case the shortness of the wheelbase was forced on us because where it lived at the time we couldn't get anything longer into the shed.
     
    It was finished in 1995 and we did about 3500 miles in it - the above photo was taken about 130 miles from home. We got bored of it in 2000 and sold it to a chap who did about 12,000 miles in it. The old girl is living down south somewhere now. We moved onto the restoration of the later S Type Sentinel (photo elsewhere) and a couple of years ago we decided that we would build another Super because they are bestest.
     
    This time round we will build it longer because the ultra short wheelbase of the last one wasn't brilliant on the road. Think SWB Series III Land Rover with tired springs and you'll know where I am coming from. So what we are aiming for this time round is something with the wheelbase and body of the Charringtons one up there with the windscreens and pneumatics of the one below it. Oh, and steam brakes and electric lights which are all period options/factory modifications.
     
    There is a bit to catch up on so it will take a few posts. If it gets too dull let me know and I will stop.
     
    Oh, and I am crap at taking pictures.
  6. Like
    JimH got a reaction from AdgeCutler in It is just so Super (Sentinel).   
    So where are we? By this point the list looked a bit like:
     
    Boiler
    Superheater
    Chimney base
    Injector
    Most of the steering box
    A steering wheel
    Windscreen hinges
    Ash pan
    Tank filter boxes
    Feed heater box and lid
    A vague idea what we are up to
     
    When we built the last one we started with an engine and then fretted about making axles and boilers and the rest of it. Now we were pretty happy that the rest of it could be built but the engine was going to be a problem. What Sentinel built was a fairly standard twin cylnder, double acting engine with poppet valves operated from camshafts (we'll come to them later). Where things got odd is that the Super has a twin chain drive. There is a sprocket on both ends of the crankshaft driving a chain to a sprocket on each rear wheel.
     
    Errr, where are we going to put the differential?
     
    After much head scratching they come up with one of the more mental ideas in vehicle design. We'll put it in the crankshaft. And in a stroke they made what would have been a difficult job of making an engine very much harder. So there was humming and hawing and then as is usually the case if you think about a problem for long enough someone solves it for you. The widow of John Keeley died and there was a big auction of all the stuff he had amassed over his life. One of the lots was the remains of a sorry looking Super engine minus lots of bits. Fortunately there was a crankcase and - most importantly - a crankshaft. The old man trooped down there with the intention of buying it come what may. A coupe of weeks later we had to do an 850 mile round trip in the LDV to pick it up. Here it is, upside down, on a pallet. The big bits that are missing are the cylinders, the camshafts, all of the valve gear and the water pump. Still, we stand a chance of getting a waggon number if we can identify it.
     

     
    Peering through the crankcase door you can glimpse the crankshaft. Pretty much everything you can see is buggered.
     

     
    Hosed down and on the workshop floor things look a bit better.
     

     
    So you take it to bits and have a look. This is the crankshaft stripped of all its shafts and gears.
     

     
    To give some idea of scale those are 3.5 tonne axlestands it is sitting on. Two people can just lift the bare crank. One of the avenues we explored was having a crankshaft made by LCR (who are an amazing company who can do some well impressive stuff) because it is way beyond our workshop capability. The estimate from LCR was that to manufacture what you are looking at there less the balance weights would be £14,000 plus yer dreaded, mate. When you saw what they were doing for the money we had no argument with the price. The problem was that it was £14K FFS. 
     
    Just to jump forward a little so you can see what it is meant to look like this is the same crankshaft once we'd finished it. I'll fill in how it got to be like this but it should give an idea of how it works. The large lumps of metal on each end of the crank are the partially machined sprocket carriers. These spin freely on the crankshaft and are driven by shafts that pass the the hollow journals. It is unbelieveably heavy by this point. You see the massive main bearings? It needs them.
     

     
    However, jump back to a close up on a couple of the diff gears. You can probably see that they are buggered.So the crank needed all new bushes (8 off), new drive shafts (2 off), new master gears (2 off) new diff pinions (2 off) and new diff gears (2 off). On top of that it needed to have the big end journals reground which we can't do so it had to go to the engine remanufacturers to be reground and that took a while for it to come back.
     

     
    So from this exercise we have a very long list of things that need to be made/found to turn this into a working engine. However, work carries on other things. The steering box, cover, top bearing housing  and crank are were all done so now it needed the shaft and nut made. This is a left handed, two start ACME thread at 1" pitch which is a bit of a tall order to machine. Its a good thing the old man has had a bit of practce making these now so that wasn't too bad (for me - it took him several days). You need to cut a square thread first then go in with an ACME form tool so you need to kep your wits about you. These days threads like this would be rolled (and beautiful they would be too) but this is an oddball one so you would need to spring for the cost of the dies which is a no no.
     

     
    Meh, not bad I suppose...
     

     
    And this is the start of the front axle. The bend in the middle is so it goes around the boiler. Originally these were forged but we don't have a massive hammer so the approach we have taken was to make a pattern and have them cast in steel. Then we simply* weld them together in the middle. This also solves the problem of machining the axle since the whiole axle won't fit in our boring machine.
     

     
    This is an extract from the parts book. Gives you a bit of an idea what the front axle beam is meant to look like.
     

     
    And some long lengths of channel were delivered. You will be a chassis one day soon.
     

     
    That will do for now. In the next thrilling installment some things are cast and other things are machined.
  7. Like
    JimH got a reaction from Manbearpig in ebay 'BARGAINS'   
    I don't think we've had this one yet. It's another from the dealer in all things thoroughbred Emergency Accountants. This time the unique appreciating asset is perhaps the most desperate use of the GTi badge ever. Not for this lad the backdrop of water features in the grounds or the stone built stable blocks. No, the cars speak for themselves and can shout through the palisade fence and weeds.
     

     
     
    To be fair to the lad he only wants a grand for this cast iron investment opportunity. I do wonder what is going to happen to the global economy over the next decade that is going to make a thirty year old estate worth 25K. Perhaps he thinks we are in for a bout of hyper inflation.
  8. Like
    JimH got a reaction from bunglebus in Audi, VW and NSU history 1970s   
    This was precisely the problem. Call it group think, corporate arrogance or the result of family being involved but if you locked a group in a room with nothing by a T1 and a T3 and the instruction to make them better you would end up with the T4. If only the design studio had got windows they might have looked outside and seen that the world had changed a few years ago and rear engined, air cooled things costing far too much were never going to shift. I suspect the problem was not helped by demand for the Beetle peaking at around the time they were designing the T4 so you can understand why they were so afraid of deviating too far from what was selling like cakes so hot their exhaust valves could fail at any moment.
     
    You look back and wonder what on earth they were up to but you have to have some symapthy with the position they were in. It isn't entirely different to when BL came to replace the spectacularly popular ADO16. There was another ball hoofed squarely into their own net.
     
    Full disclosure. My grandfather had a VW garage and my old man had dozens (quite literally) of them. There is always more room in your head for tedious air cooled shite facts.
  9. Like
    JimH got a reaction from HillmanImp in It is just so Super (Sentinel).   
    At close to the turn of the last century the Glasgow firm of Alley and Maclennan moved to Shrewsbury and changed their name to Sentinel. They developed a steam cart that became known as the Standard and because it was so much better than most of what had gone before they sold a shed load of them and made a lot of money. However, by the early 1920s the Standard was old hat and had a number of design issues (trival matters like no brakes to speak of were becoming more important as roads got busier and loads got heavier). Sentinel put their thinking caps on to design something new and then went bust. The company was kicked back into life with a name that was only slightly different put their thinking caps back on and came up with the next model. It had features that were super. Its engine was super, the cab was super and it even had a foot brake which were super. There could only be one name for a waggon (two Gs because Sentinel couldn't spell either) that was this super and that is what we are discussing here. 
     
    The Super deserved its name because despite a number of odd design features it was pretty much the sweet spot. A decent cab and brakes but without the problems of the later models.  I've posted this one a couple of times already but I can't be bothered uploading another example of a Super - they all look about the same. This is a Super Sentinel with a coke body on it.
     

     
    For the uninitiated the general idea is the boiler sits right at the front in the cab and is fired from the top. The bunker is in the cab too. You then have the twin cylinder engine slung under the chassis with a chain driving each rear wheel. Steam waggons are bad for all sorts of reasons which is why lorries have pretty much always run on diesel. They do have a few advantages. They are quiet, they produce more torque than you have heard of and they don't have gears. Open the throttle and go. They are a joy to drive on the road. Particularly in traffic.
     
    And here's the one we built back in the early 1990s. What I mean by "built" should become apparent as we go on.
     

     
    You will note a few key differences. This one has windscreens. This was a period option and are essential. It also has pnematics rather than solids. Many waggons were returned to the factory to be converted from solids to pneumatics which allowed them to run at a legal maximum of 20mph instead of 12mph. We drive our waggons on the road so solids are a non-starter. You will also see that this one is very short. Some were cut down to drawbar tractors in period, however, in our case the shortness of the wheelbase was forced on us because where it lived at the time we couldn't get anything longer into the shed.
     
    It was finished in 1995 and we did about 3500 miles in it - the above photo was taken about 130 miles from home. We got bored of it in 2000 and sold it to a chap who did about 12,000 miles in it. The old girl is living down south somewhere now. We moved onto the restoration of the later S Type Sentinel (photo elsewhere) and a couple of years ago we decided that we would build another Super because they are bestest.
     
    This time round we will build it longer because the ultra short wheelbase of the last one wasn't brilliant on the road. Think SWB Series III Land Rover with tired springs and you'll know where I am coming from. So what we are aiming for this time round is something with the wheelbase and body of the Charringtons one up there with the windscreens and pneumatics of the one below it. Oh, and steam brakes and electric lights which are all period options/factory modifications.
     
    There is a bit to catch up on so it will take a few posts. If it gets too dull let me know and I will stop.
     
    Oh, and I am crap at taking pictures.
  10. Like
    JimH got a reaction from inconsistant in Audi, VW and NSU history 1970s   
    This. In spades. And not just VWs.
     
    One of those phrases that immediately triggers my bollocksdar is "marque expert". It often translates as "someone who collected lots of brochures as a kid and still has them".
     
    It really makes you wonder if all history books are as badly and lazily researched.
  11. Like
    JimH got a reaction from inconsistant in Audi, VW and NSU history 1970s   
    This was precisely the problem. Call it group think, corporate arrogance or the result of family being involved but if you locked a group in a room with nothing by a T1 and a T3 and the instruction to make them better you would end up with the T4. If only the design studio had got windows they might have looked outside and seen that the world had changed a few years ago and rear engined, air cooled things costing far too much were never going to shift. I suspect the problem was not helped by demand for the Beetle peaking at around the time they were designing the T4 so you can understand why they were so afraid of deviating too far from what was selling like cakes so hot their exhaust valves could fail at any moment.
     
    You look back and wonder what on earth they were up to but you have to have some symapthy with the position they were in. It isn't entirely different to when BL came to replace the spectacularly popular ADO16. There was another ball hoofed squarely into their own net.
     
    Full disclosure. My grandfather had a VW garage and my old man had dozens (quite literally) of them. There is always more room in your head for tedious air cooled shite facts.
  12. Like
    JimH got a reaction from Aston Martin in Cars you didn't know existed until very recently.   
    Discussion of forgotten VWs lead me to a picture of this sorry hound. We've built a car that no one wants. How on earth are we going to make it more appealling?
     
    Well, what if we make it more wobbly and even more expensive?
     

  13. Like
    JimH got a reaction from inconsistant in Audi, VW and NSU history 1970s   
    Wandering off topic slightly this picture makes me smile. That the 411/2 was easily the second worse car VW ever built is obvious anyone who has seen a car before. That the K70 was one of those missed opportunities is equally apparent. The odd thing was them being built right next to each other. The old guard and the brave new world studiousy ignoring each other.
     

     
    People always go on about the Ro80 and what an amazing car it was because amazing cars have appalling reliability, drink fuel and bankrupt their builder. In my book it was the K70 that should be mourned. Its pin sharp body still looks bang on today while, mercifully, the 411 has been forgotten.
     
    Nice engine, though.
  14. Like
    JimH got a reaction from Datsuncog in Audi, VW and NSU history 1970s   
    Wandering off topic slightly this picture makes me smile. That the 411/2 was easily the second worse car VW ever built is obvious anyone who has seen a car before. That the K70 was one of those missed opportunities is equally apparent. The odd thing was them being built right next to each other. The old guard and the brave new world studiousy ignoring each other.
     

     
    People always go on about the Ro80 and what an amazing car it was because amazing cars have appalling reliability, drink fuel and bankrupt their builder. In my book it was the K70 that should be mourned. Its pin sharp body still looks bang on today while, mercifully, the 411 has been forgotten.
     
    Nice engine, though.
  15. Like
    JimH got a reaction from spartacus in It is just so Super (Sentinel).   
    So where are we? By this point the list looked a bit like:
     
    Boiler
    Superheater
    Chimney base
    Injector
    Most of the steering box
    A steering wheel
    Windscreen hinges
    Ash pan
    Tank filter boxes
    Feed heater box and lid
    A vague idea what we are up to
     
    When we built the last one we started with an engine and then fretted about making axles and boilers and the rest of it. Now we were pretty happy that the rest of it could be built but the engine was going to be a problem. What Sentinel built was a fairly standard twin cylnder, double acting engine with poppet valves operated from camshafts (we'll come to them later). Where things got odd is that the Super has a twin chain drive. There is a sprocket on both ends of the crankshaft driving a chain to a sprocket on each rear wheel.
     
    Errr, where are we going to put the differential?
     
    After much head scratching they come up with one of the more mental ideas in vehicle design. We'll put it in the crankshaft. And in a stroke they made what would have been a difficult job of making an engine very much harder. So there was humming and hawing and then as is usually the case if you think about a problem for long enough someone solves it for you. The widow of John Keeley died and there was a big auction of all the stuff he had amassed over his life. One of the lots was the remains of a sorry looking Super engine minus lots of bits. Fortunately there was a crankcase and - most importantly - a crankshaft. The old man trooped down there with the intention of buying it come what may. A coupe of weeks later we had to do an 850 mile round trip in the LDV to pick it up. Here it is, upside down, on a pallet. The big bits that are missing are the cylinders, the camshafts, all of the valve gear and the water pump. Still, we stand a chance of getting a waggon number if we can identify it.
     

     
    Peering through the crankcase door you can glimpse the crankshaft. Pretty much everything you can see is buggered.
     

     
    Hosed down and on the workshop floor things look a bit better.
     

     
    So you take it to bits and have a look. This is the crankshaft stripped of all its shafts and gears.
     

     
    To give some idea of scale those are 3.5 tonne axlestands it is sitting on. Two people can just lift the bare crank. One of the avenues we explored was having a crankshaft made by LCR (who are an amazing company who can do some well impressive stuff) because it is way beyond our workshop capability. The estimate from LCR was that to manufacture what you are looking at there less the balance weights would be £14,000 plus yer dreaded, mate. When you saw what they were doing for the money we had no argument with the price. The problem was that it was £14K FFS. 
     
    Just to jump forward a little so you can see what it is meant to look like this is the same crankshaft once we'd finished it. I'll fill in how it got to be like this but it should give an idea of how it works. The large lumps of metal on each end of the crank are the partially machined sprocket carriers. These spin freely on the crankshaft and are driven by shafts that pass the the hollow journals. It is unbelieveably heavy by this point. You see the massive main bearings? It needs them.
     

     
    However, jump back to a close up on a couple of the diff gears. You can probably see that they are buggered.So the crank needed all new bushes (8 off), new drive shafts (2 off), new master gears (2 off) new diff pinions (2 off) and new diff gears (2 off). On top of that it needed to have the big end journals reground which we can't do so it had to go to the engine remanufacturers to be reground and that took a while for it to come back.
     

     
    So from this exercise we have a very long list of things that need to be made/found to turn this into a working engine. However, work carries on other things. The steering box, cover, top bearing housing  and crank are were all done so now it needed the shaft and nut made. This is a left handed, two start ACME thread at 1" pitch which is a bit of a tall order to machine. Its a good thing the old man has had a bit of practce making these now so that wasn't too bad (for me - it took him several days). You need to cut a square thread first then go in with an ACME form tool so you need to kep your wits about you. These days threads like this would be rolled (and beautiful they would be too) but this is an oddball one so you would need to spring for the cost of the dies which is a no no.
     

     
    Meh, not bad I suppose...
     

     
    And this is the start of the front axle. The bend in the middle is so it goes around the boiler. Originally these were forged but we don't have a massive hammer so the approach we have taken was to make a pattern and have them cast in steel. Then we simply* weld them together in the middle. This also solves the problem of machining the axle since the whiole axle won't fit in our boring machine.
     

     
    This is an extract from the parts book. Gives you a bit of an idea what the front axle beam is meant to look like.
     

     
    And some long lengths of channel were delivered. You will be a chassis one day soon.
     

     
    That will do for now. In the next thrilling installment some things are cast and other things are machined.
  16. Like
    JimH got a reaction from Semi-C in It is just so Super (Sentinel).   
    So where are we? By this point the list looked a bit like:
     
    Boiler
    Superheater
    Chimney base
    Injector
    Most of the steering box
    A steering wheel
    Windscreen hinges
    Ash pan
    Tank filter boxes
    Feed heater box and lid
    A vague idea what we are up to
     
    When we built the last one we started with an engine and then fretted about making axles and boilers and the rest of it. Now we were pretty happy that the rest of it could be built but the engine was going to be a problem. What Sentinel built was a fairly standard twin cylnder, double acting engine with poppet valves operated from camshafts (we'll come to them later). Where things got odd is that the Super has a twin chain drive. There is a sprocket on both ends of the crankshaft driving a chain to a sprocket on each rear wheel.
     
    Errr, where are we going to put the differential?
     
    After much head scratching they come up with one of the more mental ideas in vehicle design. We'll put it in the crankshaft. And in a stroke they made what would have been a difficult job of making an engine very much harder. So there was humming and hawing and then as is usually the case if you think about a problem for long enough someone solves it for you. The widow of John Keeley died and there was a big auction of all the stuff he had amassed over his life. One of the lots was the remains of a sorry looking Super engine minus lots of bits. Fortunately there was a crankcase and - most importantly - a crankshaft. The old man trooped down there with the intention of buying it come what may. A coupe of weeks later we had to do an 850 mile round trip in the LDV to pick it up. Here it is, upside down, on a pallet. The big bits that are missing are the cylinders, the camshafts, all of the valve gear and the water pump. Still, we stand a chance of getting a waggon number if we can identify it.
     

     
    Peering through the crankcase door you can glimpse the crankshaft. Pretty much everything you can see is buggered.
     

     
    Hosed down and on the workshop floor things look a bit better.
     

     
    So you take it to bits and have a look. This is the crankshaft stripped of all its shafts and gears.
     

     
    To give some idea of scale those are 3.5 tonne axlestands it is sitting on. Two people can just lift the bare crank. One of the avenues we explored was having a crankshaft made by LCR (who are an amazing company who can do some well impressive stuff) because it is way beyond our workshop capability. The estimate from LCR was that to manufacture what you are looking at there less the balance weights would be £14,000 plus yer dreaded, mate. When you saw what they were doing for the money we had no argument with the price. The problem was that it was £14K FFS. 
     
    Just to jump forward a little so you can see what it is meant to look like this is the same crankshaft once we'd finished it. I'll fill in how it got to be like this but it should give an idea of how it works. The large lumps of metal on each end of the crank are the partially machined sprocket carriers. These spin freely on the crankshaft and are driven by shafts that pass the the hollow journals. It is unbelieveably heavy by this point. You see the massive main bearings? It needs them.
     

     
    However, jump back to a close up on a couple of the diff gears. You can probably see that they are buggered.So the crank needed all new bushes (8 off), new drive shafts (2 off), new master gears (2 off) new diff pinions (2 off) and new diff gears (2 off). On top of that it needed to have the big end journals reground which we can't do so it had to go to the engine remanufacturers to be reground and that took a while for it to come back.
     

     
    So from this exercise we have a very long list of things that need to be made/found to turn this into a working engine. However, work carries on other things. The steering box, cover, top bearing housing  and crank are were all done so now it needed the shaft and nut made. This is a left handed, two start ACME thread at 1" pitch which is a bit of a tall order to machine. Its a good thing the old man has had a bit of practce making these now so that wasn't too bad (for me - it took him several days). You need to cut a square thread first then go in with an ACME form tool so you need to kep your wits about you. These days threads like this would be rolled (and beautiful they would be too) but this is an oddball one so you would need to spring for the cost of the dies which is a no no.
     

     
    Meh, not bad I suppose...
     

     
    And this is the start of the front axle. The bend in the middle is so it goes around the boiler. Originally these were forged but we don't have a massive hammer so the approach we have taken was to make a pattern and have them cast in steel. Then we simply* weld them together in the middle. This also solves the problem of machining the axle since the whiole axle won't fit in our boring machine.
     

     
    This is an extract from the parts book. Gives you a bit of an idea what the front axle beam is meant to look like.
     

     
    And some long lengths of channel were delivered. You will be a chassis one day soon.
     

     
    That will do for now. In the next thrilling installment some things are cast and other things are machined.
  17. Like
    JimH got a reaction from barefoot in Audi, VW and NSU history 1970s   
    Fuel economy was the least of the 411's problems.
  18. Like
    JimH got a reaction from HillmanImp in It is just so Super (Sentinel).   
    So where are we? By this point the list looked a bit like:
     
    Boiler
    Superheater
    Chimney base
    Injector
    Most of the steering box
    A steering wheel
    Windscreen hinges
    Ash pan
    Tank filter boxes
    Feed heater box and lid
    A vague idea what we are up to
     
    When we built the last one we started with an engine and then fretted about making axles and boilers and the rest of it. Now we were pretty happy that the rest of it could be built but the engine was going to be a problem. What Sentinel built was a fairly standard twin cylnder, double acting engine with poppet valves operated from camshafts (we'll come to them later). Where things got odd is that the Super has a twin chain drive. There is a sprocket on both ends of the crankshaft driving a chain to a sprocket on each rear wheel.
     
    Errr, where are we going to put the differential?
     
    After much head scratching they come up with one of the more mental ideas in vehicle design. We'll put it in the crankshaft. And in a stroke they made what would have been a difficult job of making an engine very much harder. So there was humming and hawing and then as is usually the case if you think about a problem for long enough someone solves it for you. The widow of John Keeley died and there was a big auction of all the stuff he had amassed over his life. One of the lots was the remains of a sorry looking Super engine minus lots of bits. Fortunately there was a crankcase and - most importantly - a crankshaft. The old man trooped down there with the intention of buying it come what may. A coupe of weeks later we had to do an 850 mile round trip in the LDV to pick it up. Here it is, upside down, on a pallet. The big bits that are missing are the cylinders, the camshafts, all of the valve gear and the water pump. Still, we stand a chance of getting a waggon number if we can identify it.
     

     
    Peering through the crankcase door you can glimpse the crankshaft. Pretty much everything you can see is buggered.
     

     
    Hosed down and on the workshop floor things look a bit better.
     

     
    So you take it to bits and have a look. This is the crankshaft stripped of all its shafts and gears.
     

     
    To give some idea of scale those are 3.5 tonne axlestands it is sitting on. Two people can just lift the bare crank. One of the avenues we explored was having a crankshaft made by LCR (who are an amazing company who can do some well impressive stuff) because it is way beyond our workshop capability. The estimate from LCR was that to manufacture what you are looking at there less the balance weights would be £14,000 plus yer dreaded, mate. When you saw what they were doing for the money we had no argument with the price. The problem was that it was £14K FFS. 
     
    Just to jump forward a little so you can see what it is meant to look like this is the same crankshaft once we'd finished it. I'll fill in how it got to be like this but it should give an idea of how it works. The large lumps of metal on each end of the crank are the partially machined sprocket carriers. These spin freely on the crankshaft and are driven by shafts that pass the the hollow journals. It is unbelieveably heavy by this point. You see the massive main bearings? It needs them.
     

     
    However, jump back to a close up on a couple of the diff gears. You can probably see that they are buggered.So the crank needed all new bushes (8 off), new drive shafts (2 off), new master gears (2 off) new diff pinions (2 off) and new diff gears (2 off). On top of that it needed to have the big end journals reground which we can't do so it had to go to the engine remanufacturers to be reground and that took a while for it to come back.
     

     
    So from this exercise we have a very long list of things that need to be made/found to turn this into a working engine. However, work carries on other things. The steering box, cover, top bearing housing  and crank are were all done so now it needed the shaft and nut made. This is a left handed, two start ACME thread at 1" pitch which is a bit of a tall order to machine. Its a good thing the old man has had a bit of practce making these now so that wasn't too bad (for me - it took him several days). You need to cut a square thread first then go in with an ACME form tool so you need to kep your wits about you. These days threads like this would be rolled (and beautiful they would be too) but this is an oddball one so you would need to spring for the cost of the dies which is a no no.
     

     
    Meh, not bad I suppose...
     

     
    And this is the start of the front axle. The bend in the middle is so it goes around the boiler. Originally these were forged but we don't have a massive hammer so the approach we have taken was to make a pattern and have them cast in steel. Then we simply* weld them together in the middle. This also solves the problem of machining the axle since the whiole axle won't fit in our boring machine.
     

     
    This is an extract from the parts book. Gives you a bit of an idea what the front axle beam is meant to look like.
     

     
    And some long lengths of channel were delivered. You will be a chassis one day soon.
     

     
    That will do for now. In the next thrilling installment some things are cast and other things are machined.
  19. Like
    JimH got a reaction from HillmanImp in It is just so Super (Sentinel).   
    So where do you start? The same place as last time. Get the spare parts book and start scoring things off.
     

    This is the page for the rear axle. All you need is one (or two) of everything and you are home and dry. The well of spare parts is pretty much dry so you are on your own. Almost everything will need to be made. Fortunately one bit which would be very difficult to make is the injector. Through dumb luck we managed to get one.
     

     
    The injector uses steam at boiler pressure to force water into the boiler (I have no idea how). Normally the engine driven water pump does that but if you are stationary then you need an injector. How injectors work is pretty much a black art as far as I can see. The other bits in the picture are the raw castings for the windscreen hinges.
     

     
    Exciting, huh? These are two raw castings for the water tank filter boxes. Each one will soak up many hours' of machine time. Another part we got early was a chimney base. The exhaust from the engine exits up the chimney to provide induced draft on the fire. Don't worry, there will be some recognisable bits along soonish.
     

     
    Also quite early we managed to get a casting for a steering box. Here is the box in the boring machine.
     

     
    The throttle valve partially machined and bolted to the boiler shell.
     

     
    A boiler non return valve in its raw state.
     

     
    And this is another part of the throttle valve. It's called the dump valve and it makes a "Phsssssttttt" noise when you use it. The idea is that because the throttle opens and closes by hand you have a foot pedal which dumps the steam straight up the chimney away from the engine. This is handy for moving around slowly but also it is your OMG emergency brake. According to the operator's manual when things are grim you step on the dump valve, drag the engine into reverse and let go of the dump valve. The handbok describes this as "To stop almost instantaneously at risk of snashing the engine".
     

     
    This is the feed heater. The exhaust steam passes through this box as the boiler feedwater is fed through a coil inside. This improves efficiency.
     

     
    Things start to look a little more finished than others. Here is the crank arm for the steering box.
     

     
    And here is a more finished steering box and cover.
     

     
    Front and rear towing eyes. Some nice chap had a pattern made for one and we cadged the pattern to make our own.
     

     
    A new boiler top with chimney base fitted. Hole in the middle is the coal hole. It looks trivial but the boiler top was a weekend's work.
     

     
    The feedheater box machined and ready for its cladding.
     

     
    New lathes are shite. This is our middle lathe. I love Swifts. They are no Dean Smith and Grace but they're not bad at all.
     

     
    So, what you have seen is a tiny snippet of six months' of effort. What you may have noticed is no mention of an engine. This was something that had been exercising us since the start. Building everything else was not that big a deal but making an engine from scratch was going to be a big ask for reasons that will become obvious. We also needed an engine to give us a waggon number an a proper registration.
     
    Stay tuned for the next thrilling episode which can wait until tomorrow.
     
     
     
     
  20. Like
    JimH got a reaction from davehedgehog31 in It is just so Super (Sentinel).   
    One of the things that made the decision to build another Super easy was that we had a boiler lying around. We designed and built the boiler for the first one, then built a new one for the S Type and then built another three of them. However, for reasons that don't need to be gone into we didn't sell the last one and kept it back. Here is the the last one we built sitting in a support frame. A pressure vessel designed, constructed and documented to the Pressure Equipment Directive. This is not your usual try to claim that it is a repair effort and the design dossier is what might be called extensive.
     
    The grates are at the bottom and you drop coal down the top. It is a water tube design which is a copy of Sentinel's own design. It is what is referred to as a spiral pattern firebox. See below.
     

     
    Here is a firebox that we made for the S Type prior to the tubes being welded into the firebox. The are sixty 1" OD tubes. This is double the number that Sentinel used. The problem of this design is that machining the tube holes is a little tricky because they pierce the firebox at a crazy angle.
     

     
    The pattern the tubes make is rather hypnotic. The reason for this layout is that it gives a high heating area but it lets you have a hole in the middle. This is very important because that is what the coal falls through.
     

     
     
    What we also had lying around was a new superheater which was meant to go with the boiler. The superheater sits inside the combustion space and heats the steam to above saturation temperature. Higher temperature = higher efficiency. Note 944 being ignored.
     

     
    So that is what we started with. A new boiler and a new superheater that were lying round doing nothing.
  21. Like
    JimH got a reaction from davehedgehog31 in It is just so Super (Sentinel).   
    At close to the turn of the last century the Glasgow firm of Alley and Maclennan moved to Shrewsbury and changed their name to Sentinel. They developed a steam cart that became known as the Standard and because it was so much better than most of what had gone before they sold a shed load of them and made a lot of money. However, by the early 1920s the Standard was old hat and had a number of design issues (trival matters like no brakes to speak of were becoming more important as roads got busier and loads got heavier). Sentinel put their thinking caps on to design something new and then went bust. The company was kicked back into life with a name that was only slightly different put their thinking caps back on and came up with the next model. It had features that were super. Its engine was super, the cab was super and it even had a foot brake which were super. There could only be one name for a waggon (two Gs because Sentinel couldn't spell either) that was this super and that is what we are discussing here. 
     
    The Super deserved its name because despite a number of odd design features it was pretty much the sweet spot. A decent cab and brakes but without the problems of the later models.  I've posted this one a couple of times already but I can't be bothered uploading another example of a Super - they all look about the same. This is a Super Sentinel with a coke body on it.
     

     
    For the uninitiated the general idea is the boiler sits right at the front in the cab and is fired from the top. The bunker is in the cab too. You then have the twin cylinder engine slung under the chassis with a chain driving each rear wheel. Steam waggons are bad for all sorts of reasons which is why lorries have pretty much always run on diesel. They do have a few advantages. They are quiet, they produce more torque than you have heard of and they don't have gears. Open the throttle and go. They are a joy to drive on the road. Particularly in traffic.
     
    And here's the one we built back in the early 1990s. What I mean by "built" should become apparent as we go on.
     

     
    You will note a few key differences. This one has windscreens. This was a period option and are essential. It also has pnematics rather than solids. Many waggons were returned to the factory to be converted from solids to pneumatics which allowed them to run at a legal maximum of 20mph instead of 12mph. We drive our waggons on the road so solids are a non-starter. You will also see that this one is very short. Some were cut down to drawbar tractors in period, however, in our case the shortness of the wheelbase was forced on us because where it lived at the time we couldn't get anything longer into the shed.
     
    It was finished in 1995 and we did about 3500 miles in it - the above photo was taken about 130 miles from home. We got bored of it in 2000 and sold it to a chap who did about 12,000 miles in it. The old girl is living down south somewhere now. We moved onto the restoration of the later S Type Sentinel (photo elsewhere) and a couple of years ago we decided that we would build another Super because they are bestest.
     
    This time round we will build it longer because the ultra short wheelbase of the last one wasn't brilliant on the road. Think SWB Series III Land Rover with tired springs and you'll know where I am coming from. So what we are aiming for this time round is something with the wheelbase and body of the Charringtons one up there with the windscreens and pneumatics of the one below it. Oh, and steam brakes and electric lights which are all period options/factory modifications.
     
    There is a bit to catch up on so it will take a few posts. If it gets too dull let me know and I will stop.
     
    Oh, and I am crap at taking pictures.
  22. Like
    JimH got a reaction from scruff in It is just so Super (Sentinel).   
    I believe it is living Essex way. In the last photo I saw of it from a couple of years ago it was still in the paint job and lettering we put on it so it should be a pretty easy spot.
  23. Like
    JimH got a reaction from coalnotdole in It is just so Super (Sentinel).   
    So where are we? By this point the list looked a bit like:
     
    Boiler
    Superheater
    Chimney base
    Injector
    Most of the steering box
    A steering wheel
    Windscreen hinges
    Ash pan
    Tank filter boxes
    Feed heater box and lid
    A vague idea what we are up to
     
    When we built the last one we started with an engine and then fretted about making axles and boilers and the rest of it. Now we were pretty happy that the rest of it could be built but the engine was going to be a problem. What Sentinel built was a fairly standard twin cylnder, double acting engine with poppet valves operated from camshafts (we'll come to them later). Where things got odd is that the Super has a twin chain drive. There is a sprocket on both ends of the crankshaft driving a chain to a sprocket on each rear wheel.
     
    Errr, where are we going to put the differential?
     
    After much head scratching they come up with one of the more mental ideas in vehicle design. We'll put it in the crankshaft. And in a stroke they made what would have been a difficult job of making an engine very much harder. So there was humming and hawing and then as is usually the case if you think about a problem for long enough someone solves it for you. The widow of John Keeley died and there was a big auction of all the stuff he had amassed over his life. One of the lots was the remains of a sorry looking Super engine minus lots of bits. Fortunately there was a crankcase and - most importantly - a crankshaft. The old man trooped down there with the intention of buying it come what may. A coupe of weeks later we had to do an 850 mile round trip in the LDV to pick it up. Here it is, upside down, on a pallet. The big bits that are missing are the cylinders, the camshafts, all of the valve gear and the water pump. Still, we stand a chance of getting a waggon number if we can identify it.
     

     
    Peering through the crankcase door you can glimpse the crankshaft. Pretty much everything you can see is buggered.
     

     
    Hosed down and on the workshop floor things look a bit better.
     

     
    So you take it to bits and have a look. This is the crankshaft stripped of all its shafts and gears.
     

     
    To give some idea of scale those are 3.5 tonne axlestands it is sitting on. Two people can just lift the bare crank. One of the avenues we explored was having a crankshaft made by LCR (who are an amazing company who can do some well impressive stuff) because it is way beyond our workshop capability. The estimate from LCR was that to manufacture what you are looking at there less the balance weights would be £14,000 plus yer dreaded, mate. When you saw what they were doing for the money we had no argument with the price. The problem was that it was £14K FFS. 
     
    Just to jump forward a little so you can see what it is meant to look like this is the same crankshaft once we'd finished it. I'll fill in how it got to be like this but it should give an idea of how it works. The large lumps of metal on each end of the crank are the partially machined sprocket carriers. These spin freely on the crankshaft and are driven by shafts that pass the the hollow journals. It is unbelieveably heavy by this point. You see the massive main bearings? It needs them.
     

     
    However, jump back to a close up on a couple of the diff gears. You can probably see that they are buggered.So the crank needed all new bushes (8 off), new drive shafts (2 off), new master gears (2 off) new diff pinions (2 off) and new diff gears (2 off). On top of that it needed to have the big end journals reground which we can't do so it had to go to the engine remanufacturers to be reground and that took a while for it to come back.
     

     
    So from this exercise we have a very long list of things that need to be made/found to turn this into a working engine. However, work carries on other things. The steering box, cover, top bearing housing  and crank are were all done so now it needed the shaft and nut made. This is a left handed, two start ACME thread at 1" pitch which is a bit of a tall order to machine. Its a good thing the old man has had a bit of practce making these now so that wasn't too bad (for me - it took him several days). You need to cut a square thread first then go in with an ACME form tool so you need to kep your wits about you. These days threads like this would be rolled (and beautiful they would be too) but this is an oddball one so you would need to spring for the cost of the dies which is a no no.
     

     
    Meh, not bad I suppose...
     

     
    And this is the start of the front axle. The bend in the middle is so it goes around the boiler. Originally these were forged but we don't have a massive hammer so the approach we have taken was to make a pattern and have them cast in steel. Then we simply* weld them together in the middle. This also solves the problem of machining the axle since the whiole axle won't fit in our boring machine.
     

     
    This is an extract from the parts book. Gives you a bit of an idea what the front axle beam is meant to look like.
     

     
    And some long lengths of channel were delivered. You will be a chassis one day soon.
     

     
    That will do for now. In the next thrilling installment some things are cast and other things are machined.
  24. Like
    JimH got a reaction from davehedgehog31 in It is just so Super (Sentinel).   
    So where do you start? The same place as last time. Get the spare parts book and start scoring things off.
     

    This is the page for the rear axle. All you need is one (or two) of everything and you are home and dry. The well of spare parts is pretty much dry so you are on your own. Almost everything will need to be made. Fortunately one bit which would be very difficult to make is the injector. Through dumb luck we managed to get one.
     

     
    The injector uses steam at boiler pressure to force water into the boiler (I have no idea how). Normally the engine driven water pump does that but if you are stationary then you need an injector. How injectors work is pretty much a black art as far as I can see. The other bits in the picture are the raw castings for the windscreen hinges.
     

     
    Exciting, huh? These are two raw castings for the water tank filter boxes. Each one will soak up many hours' of machine time. Another part we got early was a chimney base. The exhaust from the engine exits up the chimney to provide induced draft on the fire. Don't worry, there will be some recognisable bits along soonish.
     

     
    Also quite early we managed to get a casting for a steering box. Here is the box in the boring machine.
     

     
    The throttle valve partially machined and bolted to the boiler shell.
     

     
    A boiler non return valve in its raw state.
     

     
    And this is another part of the throttle valve. It's called the dump valve and it makes a "Phsssssttttt" noise when you use it. The idea is that because the throttle opens and closes by hand you have a foot pedal which dumps the steam straight up the chimney away from the engine. This is handy for moving around slowly but also it is your OMG emergency brake. According to the operator's manual when things are grim you step on the dump valve, drag the engine into reverse and let go of the dump valve. The handbok describes this as "To stop almost instantaneously at risk of snashing the engine".
     

     
    This is the feed heater. The exhaust steam passes through this box as the boiler feedwater is fed through a coil inside. This improves efficiency.
     

     
    Things start to look a little more finished than others. Here is the crank arm for the steering box.
     

     
    And here is a more finished steering box and cover.
     

     
    Front and rear towing eyes. Some nice chap had a pattern made for one and we cadged the pattern to make our own.
     

     
    A new boiler top with chimney base fitted. Hole in the middle is the coal hole. It looks trivial but the boiler top was a weekend's work.
     

     
    The feedheater box machined and ready for its cladding.
     

     
    New lathes are shite. This is our middle lathe. I love Swifts. They are no Dean Smith and Grace but they're not bad at all.
     

     
    So, what you have seen is a tiny snippet of six months' of effort. What you may have noticed is no mention of an engine. This was something that had been exercising us since the start. Building everything else was not that big a deal but making an engine from scratch was going to be a big ask for reasons that will become obvious. We also needed an engine to give us a waggon number an a proper registration.
     
    Stay tuned for the next thrilling episode which can wait until tomorrow.
     
     
     
     
  25. Like
    JimH got a reaction from Bucketeer in It is just so Super (Sentinel).   
    One of the things that made the decision to build another Super easy was that we had a boiler lying around. We designed and built the boiler for the first one, then built a new one for the S Type and then built another three of them. However, for reasons that don't need to be gone into we didn't sell the last one and kept it back. Here is the the last one we built sitting in a support frame. A pressure vessel designed, constructed and documented to the Pressure Equipment Directive. This is not your usual try to claim that it is a repair effort and the design dossier is what might be called extensive.
     
    The grates are at the bottom and you drop coal down the top. It is a water tube design which is a copy of Sentinel's own design. It is what is referred to as a spiral pattern firebox. See below.
     

     
    Here is a firebox that we made for the S Type prior to the tubes being welded into the firebox. The are sixty 1" OD tubes. This is double the number that Sentinel used. The problem of this design is that machining the tube holes is a little tricky because they pierce the firebox at a crazy angle.
     

     
    The pattern the tubes make is rather hypnotic. The reason for this layout is that it gives a high heating area but it lets you have a hole in the middle. This is very important because that is what the coal falls through.
     

     
     
    What we also had lying around was a new superheater which was meant to go with the boiler. The superheater sits inside the combustion space and heats the steam to above saturation temperature. Higher temperature = higher efficiency. Note 944 being ignored.
     

     
    So that is what we started with. A new boiler and a new superheater that were lying round doing nothing.
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