Chuffer Davies Posted January 4, 2021 Author Share Posted January 4, 2021 Hi Mike, in hindsight you are probably correct but the way the chassis has been designed won’t permit the gearbox to be positioned as you suggest, so not an option for me on this build. Frank Link to post Share on other sites More sharing options...
RMweb Premium Michael Edge Posted January 4, 2021 RMweb Premium Share Posted January 4, 2021 I thought that might be the case but it's worth lobbing in.... I do a lot of "thinking outside the box" in regard to motor and gearbox postioning. Link to post Share on other sites More sharing options...
5050 Posted January 5, 2021 Share Posted January 5, 2021 On 03/01/2021 at 20:48, Chuffer Davies said: I'm going to build the S4 version just so I can tick an S4 locomotive off my bucket list. 1 Link to post Share on other sites More sharing options...
Chuffer Davies Posted January 7, 2021 Author Share Posted January 7, 2021 (edited) Today I've finished test building the alternate chassis for the Bachman Atlantic's 'front ender' tender. As anticipated it was not completely plain sailing but none the less I've ended up with a result that I am satisfied with. I've a couple of changes to make to the design to correct a couple of minor blunders which I will carry out in case there is anyone out there who wants a set of etches in the future? The entire brake assembly can be separated from the frames by undoing the 12BA screws. This then allows the front wheelset to be removed for painting and servicing which otherwise would not be possible because of the outside brake pull rods. One of the things I enjoy most when designing my own kits is discovering how things like brake gear actually work. I have not modelled the vacuum cylinder and brake operating lever because these cannot be seen when the model is on the track but otherwise all the levers and rods have been modelled and in doing so I now have a good understanding of how it all works on the prototype. I still have the guard irons to fit. These are separate to the frames and screw directly into the plastic footplate. I won't be able to paint the chassis until I can spray outside so it'll probably be April before this happens by which time I hope to have the loco's chassis built and ready for painting as well. Frank Edited March 31, 2022 by Chuffer Davies Re-instating Pictures 6 5 Link to post Share on other sites More sharing options...
grob1234 Posted January 7, 2021 Share Posted January 7, 2021 Hi Frank Didn't know you started this thread, so I'm very happy to have found it. Hope you had a good Christmas and New Year. Very much looking forward to your work bench updates. 1 Link to post Share on other sites More sharing options...
Chuffer Davies Posted January 9, 2021 Author Share Posted January 9, 2021 (edited) As previously mentioned the Clayton project will require a number of locomotives. Most of these will be built from London Road Models kits. A common feature of these kits is the provision of etched (flat) beading which to me is unconvincing. My preference is to use half round 0.7mm nickel silver wire. My reason for using N/S is because I was advised in the past that paint adheres to it better than to brass. I have no way of knowing whether this is true but I have taken this advice at face value. Unfortunately, I have not been able to find a supplier of 0.7mm half round N/S and so I make my own from 0.7mm wire held in a homemade jig. The jig is made from rectangular brass tube which has had two lengths of 0.3mm brass shim soldered to one surface spaced 0.7mm apart. The tube is clamped in a vice and the N/S wire laid in the grove and clamped at either end. The wire can then be filed to shape. I find that whilst filing it is best to stabilize the wire in the grove with a finger otherwise it will pull out and bend as the file is drawn across it. It only takes a couple of minutes to file a length sufficient to complete the front or back of a GN cab's sides and roof, or the side of a tender. I have another jig to assist with bending the beading around corners such as those of a cab window. This I made from the head of a 6mm bolt. This is simply a 90deg slot made with a thin razor saw blade in the head of the bolt. This slot is used to make a basic 90deg bend in the beading which can then be adjusted for radius etc. with a pair of traditional round and/or flat nosed pliers. I find the best way to attach it to the model is to tin the back face with solder and then to use an RSU (Resistance Soldering Unit) to precisely solder it into position. Edited March 31, 2022 by Chuffer Davies Re-instating Pictures 1 2 6 Link to post Share on other sites More sharing options...
RMweb Premium t-b-g Posted January 9, 2021 RMweb Premium Share Posted January 9, 2021 1 hour ago, Chuffer Davies said: As previously mentioned the Clayton project will require a number of locomotives. Most of these will be built from London Road Models kits. A common feature of these kits is the provision of etched (flat) beading which to me is unconvincing. My preference is to use half round 0.7mm nickel silver wire. My reason for using N/S is because I was advised in the past that paint adheres to it better than to brass. I have no way of knowing whether this is true but I have taken this advice at face value. Unfortunately, I have not been able to find a supplier of 0.7mm half round N/S and so I make my own from 0.7mm wire held in a homemade jig. The jig is made from rectangular brass tube which has had two lengths of 0.3mm brass shim soldered to one surface spaced 0.7mm apart. The tube is clamped in a vice and the N/S wire laid in the grove and clamped at either end. The wire can then be filed to shape. I find that whilst filing it is best to stabilize the wire in the grove with a finger otherwise it will pull out and bend as the file is drawn across it. It only takes a couple of minutes to file a length sufficient to complete the front or back of a GN cab's sides and roof, or the side of a tender. I have another jig to assist with bending the beading around corners such as those of a cab window. This I made from the head of a 6mm bolt. This is simply a 90deg slot made with a thin razor saw blade in the head of the bolt. This slot is used to make a basic 90deg bend in the beading which can then be adjusted for radius etc. with a pair of traditional round and/or flat nosed pliers. I find the best way to attach it to the model is to tin the back face with solder and then to use an RSU (Resistance Soldering Unit) to precisely solder it into position. That is a nice trick! I have made my own before but I have soldered the wire to a flat sheet, filed it to a half section by eye and then unsoldered it and cleaned it up. Your method is likely to give a much more consistent finish and doesn't need cleaning up. The late George Norton once showed me a tool he had obtained for drawing half round wire. It was a thickish steel plate, probably about 3mm or more likely 1/8th inch in those days, with various sized D shaped holes. I never saw him use it but he told me that you filed a flat on one end of the wire, fed it through the appropriate sized hole and gripped it with a very strong clamp and pulled it through and the D hole did the rest. One of those would be nice to have but I don't know where it is now or where you would get one from. There is some lovely stuff on your thread Frank. I do enjoy looking in at what you are up to. Tony G 1 Link to post Share on other sites More sharing options...
2mm Andy Posted January 11, 2021 Share Posted January 11, 2021 On 09/01/2021 at 22:29, t-b-g said: The late George Norton once showed me a tool he had obtained for drawing half round wire. It was a thickish steel plate, probably about 3mm or more likely 1/8th inch in those days, with various sized D shaped holes. I never saw him use it but he told me that you filed a flat on one end of the wire, fed it through the appropriate sized hole and gripped it with a very strong clamp and pulled it through and the D hole did the rest. One of those would be nice to have but I don't know where it is now or where you would get one from. Tony G Tony, I think what you're referring to is a jeweller's drawplate, available from various jewellers tool suppliers in a rather bewildering array of size/shapes. Andy 2 1 1 Link to post Share on other sites More sharing options...
Chuffer Davies Posted January 11, 2021 Author Share Posted January 11, 2021 16 minutes ago, 2mm Andy said: Tony, I think what you're referring to is a jeweller's drawplate, available from various jewellers tool suppliers in a rather bewildering array of size/shapes. Andy Thanks for updating us. I wondered where you could source such a device, I should have guessed. I may well check this out. Frank Link to post Share on other sites More sharing options...
RMweb Premium t-b-g Posted January 11, 2021 RMweb Premium Share Posted January 11, 2021 1 hour ago, 2mm Andy said: Tony, I think what you're referring to is a jeweller's drawplate, available from various jewellers tool suppliers in a rather bewildering array of size/shapes. Andy Thanks Andy. The name sounds familiar now you have said it. It is many years since he showed it to me and I had the name "gaugeplate" in my head. Link to post Share on other sites More sharing options...
RMweb Premium t-b-g Posted January 11, 2021 RMweb Premium Share Posted January 11, 2021 As Andy siad, a quick search throws up a wide variety! This looks like a good selection. https://www.cousinsuk.com/category/draw-plates Link to post Share on other sites More sharing options...
pete55 Posted January 11, 2021 Share Posted January 11, 2021 Half round brass wire can be sourced in sizes we need from MetalClays. Cannot find it on their website, but it is listed in their Ebay shop https://www.ebay.co.uk/itm/Jewelers-Brass-Half-Round-Wire-Half-Hard-NuGold/223791302002?hash=item341b004572:g:wLcAAOSwpDdU3lTw&var=522535891521 The only downside to using drawplates in my experience is the edge where the flat you file with your method meets the round portion is not always as crisp as you probably achieve by careful filing! Pete 1 Link to post Share on other sites More sharing options...
RMweb Premium t-b-g Posted January 11, 2021 RMweb Premium Share Posted January 11, 2021 30 minutes ago, pete55 said: Half round brass wire can be sourced in sizes we need from MetalClays. Cannot find it on their website, but it is listed in their Ebay shop https://www.ebay.co.uk/itm/Jewelers-Brass-Half-Round-Wire-Half-Hard-NuGold/223791302002?hash=item341b004572:g:wLcAAOSwpDdU3lTw&var=522535891521 The only downside to using drawplates in my experience is the edge where the flat you file with your method meets the round portion is not always as crisp as you probably achieve by careful filing! Pete You could well be right. George Norton used to produce large quantities that he then sold or put in some of his kits. So filing probably wasn't a realistic option. I have never found filing small amounts for a particular model to be particularly difficult or time consuming. I usually tack four or five lengths of wire onto a backing plate, not even bothering with a guide plate either side and it only takes a few moments Link to post Share on other sites More sharing options...
CEINEWYDD Posted January 25, 2021 Share Posted January 25, 2021 Not strictly about this thread, but can you see if my uploads on Clayton have worked?? Link to post Share on other sites More sharing options...
Chuffer Davies Posted February 4, 2021 Author Share Posted February 4, 2021 (edited) Over the last month I have been progressing the test build of my updated GN Atlantic chassis. I have now completed conversion of the Bachman model including adding some additional detail parts to the Bachman superstructure. I am relieved to say that the build was straight forward and the errors that I was aware off in the version 2 etches have been successfully corrected in version 3. The following images illustrate the build sequence: Initial Assembly of S4 Frames: With Spring Detail: The helical springs are made from 10BA studding. The Bogie: The vertical pin directly above the rear axle locates in a spacer across the main frames. The spacer rests on top of the bogie and the pin ensures that the rear of the bogie prevents lateral movement of the mainframes. The bogie’s rear axle bushes are designed to move vertically. To ensure that they can’t rotate, 0.5mm wire is bent into the shape of an old fashioned walking stick handle and soldered to the back of the bushes. The shaft of the wire passes through holes in the top bogie spacer and the excess is filed flush with the top of the spacer to stop it interfering with the lower edge of the mainframes. The Cylinders: First Test Fit Of Wheels: Although these are Gibson’s wheels I have chosen to use Ultrascale crankpins specifically because of my need to install flush fitting crankpin nuts on the front driving wheels. There is little or no clearance between the connecting rods and the front face of the coupling rods. I have previously tried installing Gibson’s crankpin nuts the wrong way round but they run eccentrically and mess up the quartering, whereas the Ultrascale crankpin nuts are designed for the job. Starting to Build Up Outside Frames: Overlays & Spring Hanger Mounts: Leaf Spring: The springs are constructed from 4 layers soldered together to give a realistic depth to the leaf spring. There should be significantly more leaves but this is pushing the limits of the etching process. Completed Outside Frames With Steps and Axle Box Casting: The casting is a London Road Models GN tender axle box with the leaf springs removed because the loco’s springs are considerably longer. Assembling the Brake Detail: The brake hangers for the front driving wheels are mounted on the inside of the frames because there is insufficient gap between the driving wheels to mount them traditionally. This is also true of the prototype. This subtlety is lost behind the front steps once the loco is fully assembled. The brake pull rods are made from 0.4mm N/S wire and are connected to the yokes with forked joints. Very fiddly to build but very satisfying once assembled. The Completed Chassis: This shows the chassis finally installed in the Bachman body. You can now see how tight the clearances are between the connecting and coupling rods. The S4 driving wheels only just fit within the splashers with little or no tolerance for side play. The front steps have been reduced to about half their original thickness to clear the connecting rods. I must hope that this won’t have unduly compromised their strength. The vacuum brake cylinders are a bit of an indulgence. Whilst virtually invisible once the loco is stood on the track, I know that they are there. There should be a third cylinder for the brakes on the rear axle but this was not possible to include once the decision to convert the fixed rear axle to a pony truck had been taken. As usual for me, current collection is by the American method whereby the loco’s chassis is live to all wheels on the nearside and the tender’s chassis is live to all the wheels on the offside. Unusually for me I have also added pickups to the offside driving wheels. I only did this because pickups were being discussed on the Wright’s Write blog on RM Web and I wished to illustrate an alternate approach to installing pickups: Awaiting Painting: This is as far as I can take this model until the weather improves and I can get outside to spray the chassis. As I have explained before I have already converted another Bachman Atlantic to (my preferred) EM gauge and this is now away being professionally painted. I needed to build a second model specifically to check the etches are correct and as building a model in S4 was on my bucket list this seemed to be the best time to indulge myself. At some point, when it is safe to socialise once more, I look forward to test running it on a friend’s S4 layout but after that it will probably become a mantlepiece model. Tomorrow I'll turn my attention to the GWR Mogul chassis the etches for which were delivered a couple of weeks ago... Regards, Frank Edited March 31, 2022 by Chuffer Davies Re-instating Pictures 8 4 1 Link to post Share on other sites More sharing options...
grob1234 Posted February 4, 2021 Share Posted February 4, 2021 Super stuff Frank. I suppose you have the luxury of not needing any side play on the leading coupled axle, nor much need for any on the rear either with the wheel base being so short. Link to post Share on other sites More sharing options...
Chuffer Davies Posted February 4, 2021 Author Share Posted February 4, 2021 1 hour ago, grob1234 said: Super stuff Frank. I suppose you have the luxury of not needing any side play on the leading coupled axle, nor much need for any on the rear either with the wheel base being so short. Yes absolutely correct. The chassis will go round 3’6” radius but in reality 4’ minimum is probably more realistic. The EM tolerances are much kinder and my EM chassis can get round 2’6” although the minimum on Clayton is about 4’ . Frank Link to post Share on other sites More sharing options...
grob1234 Posted February 4, 2021 Share Posted February 4, 2021 22 minutes ago, Chuffer Davies said: Yes absolutely correct. The chassis will go round 3’6” radius but in reality 4’ minimum is probably more realistic. The EM tolerances are much kinder and my EM chassis can get round 2’6” although the minimum on Clayton is about 4’ . Frank I worked that out subsequently, after building my own C1 (albeit in OO) because I incorporated too much unnecessary side play in the leading axle which in turn gave me clearance issues with the rods. I really like those flush fitting crankpin nuts too, they're great. Are they ultrascale too? Link to post Share on other sites More sharing options...
Chuffer Davies Posted February 5, 2021 Author Share Posted February 5, 2021 12 hours ago, grob1234 said: I really like those flush fitting crankpin nuts too, they're great. Are they ultrascale too? Yes they are but I filed them down in a mini drill to reduce the outer diameter to 2.2 mm so that they fitted inside the hole I’d created in the outer layer of the coupling rod. The hole in the inner layer is 1.6mm as normal. The idea being that both layers of the coupling rod bare onto the crank pin nut. Frank Link to post Share on other sites More sharing options...
5050 Posted February 5, 2021 Share Posted February 5, 2021 For front crankpin 'nuts' I turn a 1.5mm 'top hat' bush with a 14BA threaded hole that screws on from the front. The outer face/rim is made as thin as is practical. AG 'nuts' never seem to have the threaded hole central. Being turned I find this rather strange. Link to post Share on other sites More sharing options...
Chuffer Davies Posted March 8, 2021 Author Share Posted March 8, 2021 (edited) My latest project to convert the new Dapol Great Western Mogul to EM is not quite complete but I can’t get much further until the weather improves and I can get outside to spray the frames. I am also awaiting delivery of a specific motor from High Level Kits, but Chris Gibbon has had to put the company in Furlough because he is having problems with sourcing components. As I have said previously, whilst the Dapol Mogul is generally of a high standard, the chassis has been criticised for its poor crosshead and slide bar castings, and for the 18:1 gear ratio which apparently makes slow speed control problematic. At 210gms the model would be unlikely to have sufficient tractive potential to haul the heavier trains on our Hungerford exhibition layout. The aim of this project has been to design and build a replacement chassis utilising my now standard motor-in-tender drive system. This has allowed me to install the maximum ballast within the body of the loco including in the space normally occupied by a motor and gearbox. This has resulted in a revised locomotive weight of 330 grams, half as much again as the original model. Work on the design commenced in November last year. A general arrangement drawing of the 43xx class locomotive printed in the Great Western Journal was photocopied and imported into CAD. This was then accurately scaled to 4mm/ft so that the frames could be drawn directly over the line drawing. Dapol’s model is based on the later 53xx series the cab of which is 9 inches longer than that of the original 43xx and so I have had to extend the back of the frames accordingly. A particular feature of the prototype is the relationship of the connecting rod and the bottom slide bars. The slide bars have a milled slot at the rear to avoid the connecting rod from hitting it when the crankpin is at approximately 7 o’clock. When I previously built a model of the same prototype using the Perseverance chassis kit I resorted to filing a bevel in the slide bar to clear the connecting rod. The great thing about designing your own models is that you have complete control over the level of detail and the method of construction and so in this model I have recreated the slot. I have then slimmed the connecting rod down by adding a rebate in the rear layer of the rod to provide additional clearance. Whilst I particularly like the sound of a CSB sprung chassis running across rail joints I have not yet got my head around how to arrange things when there is a pony truck or bogie involved. I have therefore settled on a compensated chassis for the loco, the tender however uses CSB springing as compensation beams would interfere with the drive shaft from the motor to the gearbox in the loco. The overall design follows a conventional approach, the cylinders and crossheads are very much based on the Finney/Mitchell design avoiding the need for any castings. I particularly enjoy modelling brake linkage and so I have gone to town on modelling this on the Mogul and its tender. The design work was completed just before Christmas and the CAD files sent off to PPD Ltd for processing. The metal was back with me in January and a visual check did not immediately reveal any glaring errors in the etches themselves. Construction then proceeded much as for any flat packed kit. One thing I always include in my etches is a pair of axle spacing jigs that allow me to accurately space the horn guides in the frames (using the plain axles) without first assembling the coupling rods. There were a few errors that needed sorting, particularly the cylinders. I managed to bodge the cylinders back into shape and corrected any/all the other errors at the same time reverse engineering the CAD design to create a clean version. Despite my initial scepticism, the Dapol footplate has required minimal adjustment to accept the new frames and drive shaft. The hardest part was removing a couple of mounting pillars onto which the original Dapol chassis was attached, these occupy the space required for the rear sand boxes. My standard approach to securing a chassis to a loco is to use a couple of 1mm dowels into the back of the drag box at the rear of the loco and a single screw under the smokebox at the front. The following illustration shows the full extent of the design including the cradle into which the motor will be installed. I have provided replacements for the fall plate and the reach rod, the later because on some of the Dapol models the rod has a very obvious curve to it. This is a lot of effort (and development cost) to go to for just one model of course. It was always my intention to make these etches available to EM and P4 modellers wanting to convert their own Moguls. With that in mind the frames are etched with axle holes for top hat bearings so that the chassis can be built rigid if preferred. It is also not mandated to build this with the motor in the tender, it can readily be installed in the firebox if preferred. Anyone interested in acquiring these etches can message me on RM Web. My model will be completed later in the year and in the meantime I need to get back to designing and building models for Clayton. Thanks for reading, Frank Edited March 31, 2022 by Chuffer Davies Added revised weight of completed model 7 10 Link to post Share on other sites More sharing options...
RMweb Gold 57xx Posted March 8, 2021 RMweb Gold Share Posted March 8, 2021 The craftsmanship tag alone is not enough to say what excellent work you have done there, Frank. 3 1 Link to post Share on other sites More sharing options...
1466 Posted March 8, 2021 Share Posted March 8, 2021 57 minutes ago, Chuffer Davies said: My latest project to convert the new Dapol Great Western Mogul to EM is not quite complete but I can’t get much further until the weather improves and I can get outside to spray the frames. I am also awaiting delivery of a specific motor from High Level Kits, but Chris Gibbon has had to put the company in Furlough because he is having problems with sourcing components. As I have said previously, whilst the Dapol Mogul is generally of a high standard, the chassis has been criticised for its poor crosshead and slide bar castings, and for the 18:1 gear ratio which apparently makes slow speed control problematic. At 210gms the model would be unlikely to have sufficient tractive potential to haul the heavier trains on our Hungerford exhibition layout. The aim of this project has been to design and build a replacement chassis utilising my now standard motor-in-tender drive system. This has allowed me to install the maximum ballast within the body of the loco including in the space normally occupied by a motor and gearbox. This has resulted in a revised locomotive weight of 33o grams, half as much again as the original model. Work on the design commenced in November last year. A general arrangement drawing of the 43xx class locomotive printed in the Great Western Journal was photocopied and imported into CAD. This was then accurately scaled to 4mm/ft so that the frames could be drawn directly over the line drawing. Dapol’s model is based on the later 53xx series the cab of which is 9 inches longer than that of the original 43xx and so I have had to extend the back of the frames accordingly. A particular feature of the prototype is the relationship of the connecting rod and the bottom slide bars. The slide bars have a milled slot at the rear to avoid the connecting rod from hitting it when the crankpin is at approximately 7 o’clock. When I previously built a model of the same prototype using the Perseverance chassis kit I resorted to filing a bevel in the slide bar to clear the connecting rod. The great thing about designing your own models is that you have complete control over the level of detail and the method of construction and so in this model I have recreated the slot. I have then slimmed the connecting rod down by adding a rebate in the rear layer of the rod to provide additional clearance. Whilst I particularly like the sound of a CSB sprung chassis running across rail joints I have not yet got my head around how to arrange things when there is a pony truck or bogie involved. I have therefore settled on a compensated chassis for the loco, the tender however uses CSB springing as compensation beams would interfere with the drive shaft from the motor to the gearbox in the loco. The overall design follows a conventional approach, the cylinders and crossheads are very much based on the Finney/Mitchell design avoiding the need for any castings. I particularly enjoy modelling brake linkage and so I have gone to town on modelling this on the Mogul and its tender. The design work was completed just before Christmas and the CAD files sent off to PPD Ltd for processing. The metal was back with me in January and a visual check did not immediately reveal any glaring errors in the etches themselves. Construction then proceeded much as for any flat packed kit. One thing I always include in my etches is a pair of axle spacing jigs that allow me to accurately space the horn guides in the frames (using the plain axles) without first assembling the coupling rods. There were a few errors that needed sorting, particularly the cylinders. I managed to bodge the cylinders back into shape and corrected any/all the other errors at the same time reverse engineering the CAD design to create a clean version. Despite my initial scepticism, the Dapol footplate has required minimal adjustment to accept the new frames and drive shaft. The hardest part was removing a couple of mounting pillars onto which the original Dapol chassis was attached, these occupy the space required for the rear sand boxes. My standard approach to securing a chassis to a loco is to use a couple of 1mm dowels into the back of the drag box at the rear of the loco and a single screw under the smokebox at the front. The following illustration shows the full extent of the design including the cradle into which the motor will be installed. I have provided replacements for the fall plate and the reach rod, the later because on some of the Dapol models the rod has a very obvious curve to it. This is a lot of effort (and development cost) to go to for just one model of course. It was always my intention to make these etches available to EM and P4 modellers wanting to convert their own Moguls. With that in mind the frames are etched with axle holes for top hat bearings so that the chassis can be built rigid if preferred. It is also not mandated to build this with the motor in the tender, it can readily be installed in the firebox if preferred. Anyone interested in acquiring these etches can message me on RM Web. My model will be completed later in the year and in the meantime I need to get back to designing and building models for Clayton. Thanks for reading, Frank Great work , Frank , it looks superb . Ken 1 Link to post Share on other sites More sharing options...
grob1234 Posted March 9, 2021 Share Posted March 9, 2021 Looks fantastic Frank and a nice enjoyable account of what you’ve done to date. Sadly my modelling time has been drastically reduced with my new work schedule but I live in hope of snatching a few hours at the bench from time to time. Link to post Share on other sites More sharing options...
richbrummitt Posted March 9, 2021 Share Posted March 9, 2021 I’m so pleased that you decided to start a thread of your own (and that I found it). It’s hard to keep up with Wright Writes for the occasional posts that interest me. I hope that you and the family are all keeping well. Link to post Share on other sites More sharing options...
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