gowest Posted August 31, 2019 Author Share Posted August 31, 2019 robnot so clever as i have come across some problems now which i will tell you about./media/tinymce_upload/32db40051a0200f1442a052e2020f136.jpgThe problem with the servo is that the 2 small brackets each side of the brass servo body are at the wrong height in fact they are about 1.5mm too low.If I put the Hornby servo body up against the one I made you might see that with the bosses for the reversing gear level the fixing lugs over lap circled red.To correct this the old fixing points need removing and new ones made up and silver soldered in place./media/tinymce_upload/b534b328effb94e7f35c2014f66b9dad.jpgIn this picture the new fixing point have been made and the 4 fixing holes drill and you can see it fixed to the chassis.The next problem will be the supper heater it is too long and is jamming on top of the servo gear assembly so it looks like a new one will have to be built I have never under taken this change before so it will be interesting to see what happens.Also in the picture here you can see the valve shaft and that it is hanging out the front of the valve block by about 15mm too long so this will have to be shortened at so point. Link to comment Share on other sites More sharing options...
96RAF Posted September 1, 2019 Share Posted September 1, 2019 Teething troubles Ken. A man of your calibre will have them sorted out before most of us read about them.1. Servo mounting - you have already fixed It.2. Super-heater - will you be limited by the heating element. Can you make it shorter but greater diameter to compensate.3. Valve shaft - I seem to remember you have remade these in the past. It is looking bery good so far.Rob Link to comment Share on other sites More sharing options...
gowest Posted September 1, 2019 Author Share Posted September 1, 2019 Hi Robyes I have made and shortened valve shafts before and at some time would like to look into this area as I think the choice of metals are wrong and cause parts to wear out.as for the supper heaters the element inside the steel tube are shorter than the tube as I have taken them apart to repaired one or two in the passed. But having said that I do have some shorter heaters which I can try if the Hornby ones are still too large.no doubt something will happen here one way or another it's not ready for the bin just yet?ken Link to comment Share on other sites More sharing options...
96RAF Posted September 1, 2019 Share Posted September 1, 2019 I would have thought stainless steel would be OK for the shaft Ken if running in brass bearings, else case hardened mild steel, treated after machining. Can you turn SS with regular tools is it worked by grinding. Link to comment Share on other sites More sharing options...
gowest Posted September 1, 2019 Author Share Posted September 1, 2019 Robfor me the problem is that when the engines were first made the valve block was just brass with a stainless steel shaft but it was found that the valve port face encountered wear due to the pressure of the rotating valve spring and the brass port face.To over come this they started to chrome plate these brass valve block like the one pictured above but then the valve shaft being stainless steel will wear when run in a chrome bearing area as the valve block is now.with this chrome valve block would a bronze valve shaft be better or as I have done with this engine made a bronze sleeve and opened out the hole in the valve block then pressed the bronze sleeve in place and run a 2mm reamer through the hole then fitted the valve shaft which is as said too long but once cut down not a problem.above are my thoughts on changes but having said all that a bronze sleeve plus a ball bearing would make a even better wear resistance unit something more suited to GWR engineering quality.food for thought.ken Link to comment Share on other sites More sharing options...
gowest Posted September 1, 2019 Author Share Posted September 1, 2019 The supper heater there may not be many people that have seen the inside of the supper heater and how it is constructed I know I haven't so here are a few pictures of one that I cut the end off making it about 4 mm shorter /media/tinymce_upload/5693fb494a28eeabab344b9ea9945d96.jpgThe first thing I noticed after cutting the end all round with a hack saw and pulling the centre part out of the supper heater was how much dirt and rubbish came out with it the picture here shows the stainless steel centre part of the supper heater and its black and dirty.Not sure what the owner was using to run this engine as it was a chassis that I acquired./media/tinymce_upload/49e9ba17cd2d85086397adb6708a89ad.jpgI have washed these supper heaters out with acid and heat and by doing this have improved the flow of water through the supper heater./media/tinymce_upload/86d6044ef60a08722fb1d5fa419ac758.jpgStill carrying on with the changes you can see from this picture that the heater hangs out the end of the now shorter supper heater by about 8mm but I did say that the heater casing is longer than the heater element so the thing to do now is cut down this outter casing so that there is no chance of it interfering with the servo gear assembly gears ./media/tinymce_upload/b851e71a5e38aa0531d1e20f05f00738.jpgFrom this picture you can also see just how much shorter the heater is that I shortened up against the Hornby un cut version./media/tinymce_upload/b4d22f0fee713d6d7d30a211fb3d11d6.jpgLooking at the supper heater fitted to the engine things are looking a bit better with a little more space at the back end of the supper heater but the heater element still needs chopping back./media/tinymce_upload/cb02fd4bbaa881e9de35c008cbd29303.jpg/media/tinymce_upload/f02f3be1734d514909557be54062a221.jpgThe wall thickness of the supper heater body is a lot thicker than I thought and might if a size tap is available be possible to thread this back end so that the new centre can be screwed in place with a suitable gasket cement./media/tinymce_upload/01da1d453a55c30bc410b1d31aada435.jpgHornby welded there super heater inside and outside together this would be a tricky job for me to do so will try this screw in idea I might try brass as the inside section but different metals have different expansion rates. Link to comment Share on other sites More sharing options...
96RAF Posted September 2, 2019 Share Posted September 2, 2019 I’m a bit confused here Ken On the one hand there is a steam pipe leading from the super-heater to the safety valve but on the other hand there is a heater element down the centre of the inner tube with feeder wires. Both appear to be located at the same end of the super-heater, but I don't see them both in the same picture. Maybe I am not seeing things right. Edit - viewed from another angle -all is clear. Heater element goes in the centre from the right in this view. /media/tinymce_upload/72feb9dd6496176e105955950cfb5f50.png Link to comment Share on other sites More sharing options...
gowest Posted September 3, 2019 Author Share Posted September 3, 2019 Your confused how do you think I feel and I'm building the booming thing? Link to comment Share on other sites More sharing options...
96RAF Posted September 3, 2019 Share Posted September 3, 2019 Your confused how do you think I feel and I'm building the booming thing? 😉 Link to comment Share on other sites More sharing options...
gowest Posted September 4, 2019 Author Share Posted September 4, 2019 /media/tinymce_upload/a42bad5b6b07495903756d03b8b9acb9.jpgI made a new centre part to the supper heater and you can see the new part here not sure to use the gasket cement or try silver soldering the inner to the outer.The thread size that I found best fitted the inside diameter of the supper heater was 5/16 x 40 and you can see the thread in the body of the supper heater./media/tinymce_upload/76074a964ddf5d54317300dbedbf569d.jpgThe heater element was cut down by about 6 mm and cleaned up to make sure it was going to fit in the supper heater with out jamming as these heaters do get seized in place and can be hard to remove.The picture here shows the small heater with red wires the cut down heater in the middle and an uncut down heater at the bottom./media/tinymce_upload/4de1b41e733d1e2948f7e1d5d3509782.jpg/media/tinymce_upload/cb337f65cd5419c90e2c4ea269618931.jpgWith a trial fit all seemed to be working out ok so I removed the element from the supper heater and repacked the end where the wires came out with some fire clay./media/tinymce_upload/7a05df30d7e8ab9ef22eac61b357b91c.jpgWith all the parts assembled there is enough room now between the servo gear assembly and the back of the supper heater if you look back at some of the earlier pictures you can see the difference.All I need to do is try to find a place for the copper steam pipe from the tender boiler to the supper heater to go somewhere towards the bottom would be great as the boiler barrel on this engine is smaller than the A3 so might be a problem. Link to comment Share on other sites More sharing options...
96RAF Posted September 5, 2019 Share Posted September 5, 2019 Well done Ken.couple of questions...what is the internal wiring element of those heaters like, such that you can crop them for length. I would have thought a potted ceramic cartridge inside the metal sleeve and hence not reworkable....will the shorter super-heater be man enough to keep the steam up to par for reliable controlled running or will it run out of breath - time will tell I suppose. Link to comment Share on other sites More sharing options...
gowest Posted September 5, 2019 Author Share Posted September 5, 2019 Hi Rob all good questions the actual guts of the element are shorter than the metal sleeve this is to allow a good quantity of cement to be applied to support the wires coming out so by removing 6 mm of this metal tube you are reducing the wire support but if you want a smaller element overall then this is worth a try.the element has a ceramic sleeve inside the metal tube this ceramic former fills the metal tube and has 2 small bores through it so that the heater wire runs up one bore in the ceramic sleeve makes a U turn at the end of the ceramic former and then turns back down the second bore and the 2 supply wires are then stop welded onto the element wire the end with the U turn has a heat prof cement to seal off the end and as I have done the end with the wires feeding from it again has cement to seal this end job complete.as for the very small heater with the red wires the wattage is the same only its size is questionable so you maybe right in as much as it has a limited area to conduct heat and therefore produce enough steam to run the engine but only by testing this can it viability be assessed.kenhope that this is of some help Link to comment Share on other sites More sharing options...
96RAF Posted September 5, 2019 Share Posted September 5, 2019 Thanks KenI presume the actual heating element is plain resistance wire and doesn’t have to be coiled around the ceramic former like it would in a radiant fire. Link to comment Share on other sites More sharing options...
gowest Posted September 5, 2019 Author Share Posted September 5, 2019 Actually your right it is resistance wire wound like a spring the cross section is about 1.5 mm so it's very smallken Link to comment Share on other sites More sharing options...
gowest Posted September 9, 2019 Author Share Posted September 9, 2019 Still plenty to do before the boiler side of things are needed so a few of the other jobs were carried out one being the valve rod which meant cutting it down by about 10 mm which I did to the end with the flats and under cut and small turned down area. /media/tinymce_upload/24684a508f12244e0cb071f873f85e28.jpg/media/tinymce_upload/b9f18f19ed7dc4b3d6a201f7c36f0d57.JPGThis was all carried out and next came the valve block as I had machined off the fixing points to this along with the screw threaded part on the cylinder block see picture above /media/tinymce_upload/1cc808cc8168f3be35e712e520de5974.jpg2 new fixing points had to be added these would be drilled in place on the under side of the cylinder block into the valve assembly and the holes in the valve block taped 1.2 mm the new screw holes were then counter bored and screws fitted in place as in the picture here labelled A.The chassis area further back had a small part milled off and 2 screw threads made in it to take a brass plate to mount the front bogie wheels to labelled B./media/tinymce_upload/e118a44665eca7641e7a6089403edea2.jpgThis then can be seen here with the wheels fitted in place the wheels and bogie were a Hornby type as the kit one was too involved and lacked weight./media/tinymce_upload/0e822a017f1b5aeb73173b7381786838.jpgThere was a section of chassis just behind the electric motor that might just be space enough to fit my small printed board that had the motor control components on.And still further back a second space for the regulator indicator printed board.The electronics for this engine was a copy of the system used on the Lord Nelson engine.Again space was a problem plus heat a cool place would help keep the electronics safe. For this tank engine a new idea was needed for the indicator system and this is what I have come up with./media/tinymce_upload/8f0dcb924aff90d55abd615c60a1f2dc.jpgIn the drawing here is the positions for the 2 printed boards one is the motor control board the other is the indicator light.The motor control unit was going to be solid state electronics which would be fitted in the space behind the electric motor as said.The back far end of the under side of the chassis is hoped to be large enough to house the indicator PCB. /media/tinymce_upload/d4fae17ac9c2134421072927bb4c2305.jpgTo connect the two areas together a hole was drilled through the web of the back end of the Hornby chassis thereby linking the 2 compartments as picture above. /media/tinymce_upload/44511caa78afa86101ac3bb82e8c1ab5.jpg/media/tinymce_upload/75bc623664d36d54083cecac73a0b038.jpgAlso to turn the back portion of the chassis into a box so that the indicator PCB can be fitted out of sight 2 brass plates fixed in place by screws was added the chassis had a small area machined off to accommodate these brass plate so that they would be flush with the rest of the Hornby chassis./media/tinymce_upload/99e11f8f555b6e21da50f4c8ce7bd639.jpgThis drawing shows the idea for the regulator indicator light which will form part of the engines rear oil lamp this will mean the driver must look at the lamp to see what is happening and as the lights change from white to red he can be ready to drive off./media/tinymce_upload/3a9b2f94340304bb6bb7fd563813350c.jpgHow it WorksThe driver indication is achieved by using a 2 colour LED White/Red with the regulator shut the transistor TR1 is conducting as power taken from the Motor Control PCB supplies voltage to R1 which makes TR1 conduct so turning ON the white LED light showing engine stopped.Once the regulator is opened the steam pressure inside the oil tank increases and the pressure switch will close.This will then supply volts to the bridge rectifier BR1 and via C1 a DC voltage is passed to R3 at its base so turning ON TR2 the emitter will switch on the LED and it will then change from White to RED at the same time sending the base of TR1 low and so turning OFF the white LED.NotesIt might be possible to do away with R1 and TR1 marked in blue as once the red LED comes on the white LED will maybe not be noticeable so saving space on components but this has to be checked out on tests when the LED’s turn up. Link to comment Share on other sites More sharing options...
Huwsie Posted September 10, 2019 Share Posted September 10, 2019 Ken - you amaze me... I think you amaze us all! Link to comment Share on other sites More sharing options...
gowest Posted September 10, 2019 Author Share Posted September 10, 2019 HuwsieThanks for the kind comments I'm glad you find it so interesting I feel happy that all the above just might work but reading it through again on the wiring diagram if the red LED is brighter than the white light then Tr2 and R3 can be left out making the indicator PCB even smaller but tests on the LED will have to be carried out when it turns up Ken Link to comment Share on other sites More sharing options...
gowest Posted September 10, 2019 Author Share Posted September 10, 2019 /media/tinymce_upload/81d8728f0c1fc7890d6985abd37b7a59.jpgThe pressure switch taken from the Lord Nelson build that I made and is going to be use on this engine Link to comment Share on other sites More sharing options...
Muzza Posted September 11, 2019 Share Posted September 11, 2019 Ken, I agree with Huwsie - you do amaze us.It's not that you require any superpowers to do what you do, but you come up against problems that would cause most of us to give up and you find a way around them.I guess it is also the breadth of your knowledge that sees you come up with one innovative solution after another.It's such a pity Hornby didn't have you on staff 10 years ago. Imagine what could have been in the Live Steam catalogue. Link to comment Share on other sites More sharing options...
gowest Posted September 11, 2019 Author Share Posted September 11, 2019 Muzza10 or more years ago I think I would have fell out with the people running Hornby then but times have changed and for the better the new team have model railways at heart and it is shown but the number and quality of models coming out of the company these days this is long over due and should put Hornby back at the top of the model railway manufacturing busines.i still have nightmares about the scraping of all the old moulds some just might have lent them selves to a fleet of new live steam engines but I think they will have to wait as the priority must be to turn Hornby around which they are going.as for this engine we are not out the woods yet I can see things going wrong just when it looks like they are going great for its then that something I've missed bites you in the rear?thanks for your thought as we break new ground.Ken Link to comment Share on other sites More sharing options...
96RAF Posted September 12, 2019 Share Posted September 12, 2019 Well said Ken.Keep the faith, as you have not failed to overcome these problems in the past, by way of clever engineering.One of your ‘out of the woods’ innovative fixes could well end up as the standard go-to part for new build. Link to comment Share on other sites More sharing options...
gowest Posted September 12, 2019 Author Share Posted September 12, 2019 The LED’s turned up today which were yellow/red 2 colour type so a quick test showed that if the yellow LED is powered up and kept on when the red LED is switched on it does over power the yellow and it looks like it a single red LED this meant that most of the component in the diagram can be done away with making it a much more simple circuit. /media/tinymce_upload/25033c12ec7d810269af853a97e99a3c.jpgThis picture is of the yellow LED powered up though it might look not quite right as the pictures here do not seem to photograph or give the true colour/media/tinymce_upload/66cea6b99aabfe0cdd6db0664d6b6e7e.jpgThe next picture is with the yellow LED still on but now with the red LED powered up and the red LED is the predominate colour so the small printed board will need far fewer components. you can always add a resistor in the pos lead to the yellow LED making it less bright so the red will show brighter and do away with any hint of a yellow light./media/tinymce_upload/f6a9f5ab0088a80c0bc8854baab3227f.jpgHere is the oil lamp that will fit to the back of the engine with the fibre optic cable fitted in place./media/tinymce_upload/e035baf5eba3699f47d3a35cfe3512d9.jpgAs the above tests carried out discovered that the red LED over powered the yellow LED a revised circuit was drawn up with less components as pictured here./media/tinymce_upload/c79dceb25f6b70621b6bfda63831aca8.jpgWith the oil lamp in position further tests were carried out and this looked to be the answer to the regulator/indicator idea so some work on the electronics can be undertaken and the 2 printed boards made up and fitted in place.Next will be to carry on with the mechanical side of the engine and parts like the following.Rear wheelsConnecting rodsCross headsWhistleSafety valveRegulator rodPipe workBoiler Link to comment Share on other sites More sharing options...
gowest Posted September 13, 2019 Author Share Posted September 13, 2019 Before I go on with this build I was looking back at the pictures of the super heater that I cut up and all the black stuff I found was inside I thought if this super heater had come from an A4 engine was it possible that after some runs and the owner put the engine away could it be that as the tender boiler cooled down a vacuum built up in the tender boiler and if any oil was left in the oil tank might it get drawn into the first section of the supper heater nearest the oil tank and on the next firing this oil would burn and blacken the inside of the super heater?if this is the case then a valve to allow air into the tender boiler would stop the oil entering the supper heater or maybe unscrewing the water filler screw will do the same thing and allow air into the tank?i said it might be an A4 but it could be an A3 I only suggested an A4 as the oil tank is closer to the supper heater than that of the A3 Link to comment Share on other sites More sharing options...
96RAF Posted September 14, 2019 Share Posted September 14, 2019 Good thinking Ken. Any black gunge would act as an insulator and likely degrade the super-heater performance. In the back of your workshop you probably have a substance analyser (you seem to have most everything else) which would tell you if it was oil residue. Failing that see if scrapings will burn and give off that characteristic steam oil smell. Link to comment Share on other sites More sharing options...
gowest Posted September 14, 2019 Author Share Posted September 14, 2019 Good thinking Rob will try and see what smells I get also have a fix in mind for the system to let air after a run and as it cools down will be in the work shop this afternoon making a new part?ken Link to comment Share on other sites More sharing options...
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