gowest Posted June 24, 2016 Share Posted June 24, 2016 /media/tinymce_upload/237ec6dae1b972134f25d53f473c9fe7.jpgHiI have over the last year thought about an engine I would like to build which my grandfather would have made parts for when working a Stratford Works in the 1900's then a GER company this engine is a 4 6 O B12 with inside cylinders and painted a nice blue. It's the inside cylinders that will be the problem and adapting the Hornby parts to suit would be a real challenge. I have some ideas on the design and the new inside cylinder block but first the model it self needs to be built so have made a start on the engine as can be seen.Once again a brass kit is the starting point and the build is under way this is needed to get an idea as to what and how part will need to fit./media/tinymce_upload/7f8720fc71b432a3fe28efc4d86b4ef2.jpgThe cranked axle is on the leading set of drivers so that needs to be made but unlike the picture here the centre valve drive eccentrics are not needed so this will give extra space on the axle for the two cranks.The crank webs are unbalanced if you look at the picture unlike other engines but relying on the weights in the wheels to give the correct balancing./media/tinymce_upload/5964d73b4ead3032c63bca8ef001a879.jpgYou can see in this picture the Flying Scotsman wheels in green these were machined down a little and the rubber tyres are on the front set of drivers.What and how this is all going to work I have no idea? Link to comment Share on other sites More sharing options...
96RAF Posted June 26, 2016 Share Posted June 26, 2016 Looking forward to following your usual write ups as you make progress on this one GW. Link to comment Share on other sites More sharing options...
gowest Posted June 29, 2016 Author Share Posted June 29, 2016 /media/tinymce_upload/fd5cb274fe1397647aabceb3fa2608d6.jpgThe maximum width of the cylinder block is about 12.5 mm as you can see from the picture above.Larger than this might cause the front bogie wheels to fail on the cylinder outside edges.On the Hornby live steam the cylinders are 6 mm in diameter but these look like being too large when looking at the overall cylinder block.5 mm or 5.5 mm might be a better size and by using the smaller cylinder the boiler pressure could be increased to 35 psi to overcome any loss in performance. /media/tinymce_upload/a5c710c4468eccc96375b1c46a64c176.jpgThe A4 and A3 have different size pistons they are both 6 mm in diameter but the A4 has a longer piston as you can see from the picture above. Other differences are in the construction of the cylinder end covers which are not the same and the piston rods are different sizes to, also the construction of the pistons are different in as much as the A4 piston and rod are all made in one where as the A3 is an assembly with a screw holding the piston to the rod.I think i will have to make 5 mm pistons and to the same design as the A3 engine and use Hornby A3 piston rods to save time. Link to comment Share on other sites More sharing options...
gowest Posted June 29, 2016 Author Share Posted June 29, 2016 /media/tinymce_upload/e69931137aba9972c57239e5af5364c0.jpgI thought I'd put old grandfather back up on the forum he's on the left hand side with a white hanky on his head thats George and ive add a ring around his head, i never met him as he died from fumes on his chest in the black smith shop and my father was only about 8 years old.and they say the good old days? Link to comment Share on other sites More sharing options...
gowest Posted July 9, 2016 Author Share Posted July 9, 2016 Now to make a start on the cylinder block I though that if I kept to the Hornby A3 piston I might be able to fit the cylinder block as most of the block is tucked up under the smoke box and forms part of the smoke box saddle.So starting with a square of brass bar 1” x 1” I marked out the 2 cylinders putting them as close together as I could. In time I will mill away as much of the brass as I can in the hope that they will fit more on than in the frames./media/tinymce_upload/985ee5948298801e0b4385fbec181c3a.jpgWith the brass clamped to the milling table a pilot hole of some 2.5 mm was drilled, then opened out in 3 stages to the final drilled size of 5.5 mm/media/tinymce_upload/d5ec033ad1b8b147705d820195337eda.jpgDrilling the final hole at 5.5 mm the holes do not go right through the brass bar but stop short leaving about 2 mm of metal as I do not want holes in the table, I can drill them right through on the pillar drill as the drill will now follow the holes in the brass made by the mill to a much higher standard than the drill./media/tinymce_upload/d73866e87305c6ae5324d6debaaa78c6.jpgabove drilling the hole 5.5 mm ready for reamingI can also using the pillar drill and a 6 mm reamer to finish the holes to the final size of 6 mm./media/tinymce_upload/973a161900d9844b7a1f19a7e8ec6811.jpgNow we have 2 parallel bores and as luck has it they look to be in the right place both sides of the block of brass bar not running out of line as below./media/tinymce_upload/c275fa1b6effc02af923e464f58914f6.jpg/media/tinymce_upload/d2026780f270eaa4cefb756c0455c515.jpgThe Hornby A3 piston fits a bit on the tight size but can be polished out a bit for easy running later./media/tinymce_upload/c963eab3aed6d149f69d46910599418c.jpgNext will be the cylinder covers the drawing below gives some idea of the design for the covers the front one I think will be like the Hornby and soldered in place the back cover need to be just 20 thou bigger than the 6 mm cylinder bore, a hexagon cover will not have the room to rotate with a spanner so instead the part of the cover that supports the piston gland and O ring will be hex or square so a spanner can be used to tighten the cover into the cylinder block./media/tinymce_upload/c07c10c68cb80d6c33ca75ffd788357a.jpg Link to comment Share on other sites More sharing options...
gowest Posted July 12, 2016 Author Share Posted July 12, 2016 The end covers and gland nuts were made as the drawings and all seem to work ok /media/tinymce_upload/60e1ac02214edc767cb109673be4377d.jpgMaking such small parts in a large lathe is a bit of a challenge a much smaller lathe like a watch makes lathe would be a bit easier.The end cover was made in brass and the nut was made from bronze this is to give good wearing and as this forms what would be the crosshead for the piston rod support as the A3 and A4 engines the crossheads are just for show and do not carry any real loading from the piston rod./media/tinymce_upload/84a7a5e2c2c2858e1dd404dbe0ac405b.jpgThe cylinder block now needed to be cut off from the square bar so it was clamped once more onto the milling table and clamped in position.The material that wasn’t needed was milled away to leave just the new cylinder block./media/tinymce_upload/daf868e6aba70ec898f97eec1ac69502.jpgThe machined suffices were then finished on a belt sander.All the main parts of the inside cylinder are here and the cylinder block is about 6 mm too long and will need to be cut down before the front covers are soldered in place./media/tinymce_upload/ce14d2cbb4a04c4f87bbe401f220f89b.jpgA 6BA spanner gives the right fit to the cylinder cover square body./media/tinymce_upload/c81f9016f813b7128dd4734a5d6a74b4.JPG/media/tinymce_upload/8b4a53e659fe4738e8bf15d595645a45.jpgWith one cylinder built up things look as if they just might work the only thing to finish the job will be to mill in the steam passages.. I wonder what old granddad would think if he were here now?These small parts are very easy to loose and not that heavy to pick up I say this because they used to say the lightest thing on the railway was the wage packet Link to comment Share on other sites More sharing options...
walkingthedog Posted July 12, 2016 Share Posted July 12, 2016 Great work Gowest, I wish I had room for a lathe. Used to love lathe work. Link to comment Share on other sites More sharing options...
96RAF Posted July 12, 2016 Share Posted July 12, 2016 Somewhere else on the forum you say you are not an expert Gowest. I would describe you more as an artisan and a very skilled one at that. I see a born engineer who can work out the answer to a problem, then take raw materials and make the parts to build that answer. I may be a qualified engineer, but I stand in awe of the model engineering you produce. Would that I could do the same.Rob Link to comment Share on other sites More sharing options...
gowest Posted July 12, 2016 Author Share Posted July 12, 2016 WTD and RAF96Thanks for the kind words here but its not running yet and may never if things dont come together and work as i think they must there may be many more problems around the corner.Thinking through the build of this loco and how parts need to be made can be dificault and with ideas going around in my head need to be thought through and i find that in the late evening is a good help and so is the bath and tomorow is bath night so could be a long time in the bath designing might just come out more wrinkly than i went in? Link to comment Share on other sites More sharing options...
96RAF Posted July 12, 2016 Share Posted July 12, 2016 @WTDI've often looked a model engineering lathes and thought YES I NEED ONE, but I've never actually been able to justify buying one. Now the physical bits of me have degraded beyond the levels necessary to achieve the necessary mechanical tolerances of a project I must admit to myself that I will never get one. @GowestThe last time I described someone as an artisan was a chap hand carving bas-relief townships and notable buildings like Reims Cathedral from small photographs in tufo walls of a mushroom cave in France many years ago. He was very good on the tools as well. Link to comment Share on other sites More sharing options...
96RAF Posted July 12, 2016 Share Posted July 12, 2016 duplicate post deletedtardy response by ipad on dodgy mifi dongle internet.. Link to comment Share on other sites More sharing options...
gowest Posted July 13, 2016 Author Share Posted July 13, 2016 RAF96Seeing the skills that others have always been something that i lack i had a freind that was also a model engineer and he was building a traction engine and he must have made 4 times the number of parts he needed to get it to a standard that he would fit to his model he had a saying "don't spoil the ship fot half penny of tar"now for the cranked axle a drawing here gives some idea as to what is needed./media/tinymce_upload/52e7a7cbba34c836d92026e3e40d2b21.jpg Link to comment Share on other sites More sharing options...
96RAF Posted July 13, 2016 Share Posted July 13, 2016 @Gowestthere is truth in that saying because if a part is not made right it wont run right. Your fabricated crank being a typical example especially taking account of the size of its component parts and any distortion due to the silver soldering and cutting clear processes. For anyone working in old measurements 3mm is an eighth of an inch. Those crank webs are a sixteenth of an inch thick.Rob Link to comment Share on other sites More sharing options...
gowest Posted July 13, 2016 Author Share Posted July 13, 2016 RAF96Yes you are right it is hoped that after cutting the axle will still run true I am trying to use steel on the assembly not brass as brass mat cause a problem in the assembly I have made crank shafts like this before in a 3/4 scale traction engine And it came out ok but with this small scale you never know and you like me must be a feet and inches man and to try and keep it metric just adds to the maths which was never very good at did you know that 6 out of 4 people can't do fractions Link to comment Share on other sites More sharing options...
gowest Posted July 14, 2016 Author Share Posted July 14, 2016 Making a start on the crank starts with marking out the shape of the webs and hole centres on a strip of mild steel for 4 of these very small webs are needed.And just like my friend had said earlier I was going to make more than 4 so that the best looking ones would go into the engine.Not sure any of these look that good but he wont know./media/tinymce_upload/2ee194d78fa6012bd2010ebbba832c81.jpgBoth holes in the webs are drilled 2 mm the larger hole is 1/8” for the Hornby axle and can be drilled and reamed laterTo make a nice radius on the ends just turn up a small boss the width of the web and with a 2 mm spigot on it to locate in the drilled holes then file down using the boss as a guide to file to and this should give a good radius./media/tinymce_upload/c9abcc77c714ce393ee0e5612c497c01.jpgI wanted to make this part as strong as I could given the space as if it was too light a manufacture it might bend later on and the wheels would then run out of line.Having said that the bearing ends of the axle are a little on the small size but the final fit is yet to come and we need some crank pins to complete the little cranked axle then it will be ready to silver solder./media/tinymce_upload/c84f3debc48275c6bb90c6b0eb8093b3.jpgI was not sure the correct position of the cylinder block in the frames of this engine so I got in touch with the North Norfolk Railway as they have a B12 and thought they might know and an email came back “the cylinders are mounted horizontally and low in the frames with the valves above.Hope that helps"Yes and no as us live steamers know that front boggy wheels can short on the cylinders on bends and as my cylinders are a bit large might be a problem later on./media/tinymce_upload/b77e4ad0d5c1eba287e7ba8c9db35380.jpglets look once more at the B12 crank axle/media/tinymce_upload/8abc81420273489acae50d3f96bf04f5.jpg This picture gives the crank webs positions and the very large wheel weights to over come all them great chunks of metal flying around both on the axle and the connecting rods on the wheels. Link to comment Share on other sites More sharing options...
96RAF Posted July 15, 2016 Share Posted July 15, 2016 This place may be of use Gowest: Link Admin edit: Shortened link Link to comment Share on other sites More sharing options...
2e0dtoeric Posted July 15, 2016 Share Posted July 15, 2016 Watching with interest, but I wouldn't know where to start! 😎 Link to comment Share on other sites More sharing options...
gowest Posted July 16, 2016 Author Share Posted July 16, 2016 RAF96thanks for the information I took a look and see that they have drawings of the engine S69 and have sent them an email asking if the drawings give details of the steam workings more than the overall layout. If i still lived in Chelmsford Essex I could have taken a trip to the N N Railway to photograp the engine in detail. In fact many years ago my friend Nick Hodge help start up the railway in the very early days but then I think they only had a few bit like a diesel shutter and a coach.As for where to start most of the builders of steam engines I have met tend to work by going through the drawings and finding a part that looks easy to make and make it leaving the more difficult parts for later I can remember making a traction years ago and the cylinder are very involved as they have to fit the boiler which is round and be a good gas tight fit this part is called the saddle and must be machined spot on to keep the cylinder bore parell to the boiler and the right hight and angle from the boiler. So like this engine I should be making the top parts with steam passages in to fit the Hornby valve unit to but keep putting that off.conneting rods and how they should fit is the next part and of cause the cranked axle but waiting for bits in the post before the final assembly. Link to comment Share on other sites More sharing options...
gowest Posted July 17, 2016 Author Share Posted July 17, 2016 Now with all the parts made it was time to silver solder them all together and finish the cranked axle All seamed to be going well until it came to the cutting of the axle in-between the webs.This cutting operation was done with one of these small hand operated electric tools./media/tinymce_upload/3d2b662f9e72741a7b3ce8cc5018639b.jpgBy making 2 cuts the unwanted sections of the Hornby axle were removed and then just a clean up of the surfaces and the axle was finished and finished it was for as I was filing the axle to clean it up one of the stub axles fell off see picture. %$@! which translates into some old English word for bother all that work gone out the window.There was no way this could be successfully fixed as the axle not only needed to run true but the quartering of the wheels had to be correct so it was dustbinized ./media/tinymce_upload/4f2625568513f2fc5749537ba0f5fd74.jpgSo making a new start all over again but this time I had a new idea for the centre web by making it in one bit, in an L shape this would not only save space but would keep the quartering better of the webs./media/tinymce_upload/e4a522366521530f8f343838272668d5.jpgThe new part pictured here and a new addition to this axle assemble was going to be the fitting of bearings.The Hornby axle had its ends turned down so that these ball bearing can be fitted which would make for a free running engine and longer bearing life./media/tinymce_upload/17f3d222c8093eb27e22db0e844830b9.jpgYou can see the new middle web pictured here with the large hole for the axle and the 2 smaller holes for the crank pins. As before the unwanted axle sections were cut out and the axle cleaned up this time it all seemed to stay in one lump.The new bearings were fitted and the axle was finished all that was needed now was to fit the wheels and roll the complete assembly along the table and see that there was no wobbling of the wheels/media/tinymce_upload/0e4b9a1ca5621e44077d5491623fb15c.jpg/media/tinymce_upload/5a8b3d8428d6c740954513ae50590f8f.jpg/media/tinymce_upload/78fca525eb07356efe2405e36b8367e2.jpgAfter this rough test it looked to be fine just as if it was a plain straight axle so now for some axle box horns as the axle would not pass through the bearing in the frames because of the cranks a similar idea to full size engines would be needed so that the cranked axle could be dropped into the frames from the bottom and a plate with 2 screws would then clamp the bearing in the frames and stop the axle moving about./media/tinymce_upload/69929935a50b5c792c26647f7dad056d.jpgIf you look at the 2 pictures above you can see the very large wheel weights which leave very little spoke from the weight to the wheel centre.These would need to be added to the Hornby wheels cast in say Araldite Link to comment Share on other sites More sharing options...
96RAF Posted July 17, 2016 Share Posted July 17, 2016 Well recovered Gowest, good bit of lateral thinking to work that alternative out. Link to comment Share on other sites More sharing options...
walkingthedog Posted July 17, 2016 Share Posted July 17, 2016 This is so interesting. Proper model engineering. More please. Link to comment Share on other sites More sharing options...
gowest Posted July 20, 2016 Author Share Posted July 20, 2016 The wheel weights were cut out from some thin bronze sheet and glued in place as in the picture here./media/tinymce_upload/9cde42747f65a41919f5683396cf106d.jpgThis like other project I have done you tend to keep thinking of problems and how different parts will come together.The axle box horns I think I might have solved and a rough drawing here to show what's needed. Milled from brass angle./media/tinymce_upload/b75c0295dcf5739e689121d1efd3cc98.jpgAnother part will be the connecting rods and these to will be milled from brass and if possible made with a split big end held together by 2 small screws./media/tinymce_upload/a0729f38eafd0a2ce50f55277f1e7994.jpgFrames for a test model may be a good idea just to see the general arrangement of components like the cylinders and wheel alignment boiler and chimney./media/tinymce_upload/1ecf96cea89be817e718ed10e5aa5149.jpgLooking at the A3 the cylinders and piston rods that they point to the dead centre of the front axle and the cylinders on this engine are the same but inside the frames.I believe I’m right in saying that among early engine designers that to keep the working parts of an engine hidden away made for a better looking and cleaner engine and it was less likely to frighten the general public others here may have a better idea.A long way down the line but things to think of is the tender such a small box on wheels when up against the much larger A3 tender so some head scratching on this one see the pictures./media/tinymce_upload/f3b42e622e81a3ce7344b1181f62af52.jpg/media/tinymce_upload/9d98959a7f624c5c9214334d211b1e4a.jpg Link to comment Share on other sites More sharing options...
96RAF Posted July 21, 2016 Share Posted July 21, 2016 A couple of real challenges there Gowest:1. Those big end screws will be so tiny as to be impracticable. how about making the big end with a slot, such that a closing block could be inserted from the right hand end and pinned in place from top to bottom on your drawing. A picture would be worth a thousand words So maybe this rough sketch will help visualise it.Dynamic balance may then be a problem If the big end is extended thus.2. Similarly for the driver axles could you not use a removable frame part to locate both at once with a single locking screw.3. The small tender will limit boiler room and hence space to fit the heater and other bits and bobs.That FS must be about the grubbiest loco I have ever seen, and people fret over a bit of oil smear from a smoke unit. /media/tinymce_upload/ca4b74aaff61d670bd1f8874a4fbd40b.jpg Good work and keep posting as you have at least a couple of us enthralled. Link to comment Share on other sites More sharing options...
gowest Posted July 21, 2016 Author Share Posted July 21, 2016 Just thinking of this engine and life I wish I had had spoken to my father more about his time on the railway and as many of our family also spent there working life working for the different companies must have loads of tales to tell. There was even one that was the manager of Stratford works many years ago and I should have asked him about life all them years ago to late now, one relative uncle Norman that's still with us worked on the London Underground in the signalling department like my father on BR and when they got together my father would pull his leg by saying "it's not a real railway just an underground tram way" which always made my uncle laugh. Link to comment Share on other sites More sharing options...
gowest Posted July 21, 2016 Author Share Posted July 21, 2016 RAFlike the idea of the big end and this can be made as you say maybe with one screw great to have someone to bounce ideas off well give it more thought and draw up your idea.as l now looking at the FS picture does look a bit grubby these are steam engines which like full size are a total loss oil system unlike a car engine that keeps pumping the same old oil round and round.as most of us buy from flea bay you never know what you are getting but as with all my Hornby engines they are in the best of machanical condition and it was always the pigs that were rebuilt into these new live steam models. But not many none runners out there now. Link to comment Share on other sites More sharing options...
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