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I am a member of the Shipley Model Railway Society and for the last several years I have been with a group of members building a new exhibition layout - Clayton - in EM gauge.  This layout is being documented elsewhere on RM Web 

The layout is currently locked up in the club rooms which are themselves on the top floor of a Bradford sports centre to which currently we have no access because the Sports Hall itself is shut.  If truth be told even if we had access I would not feel safe attending until I have been vacinated.  This has not completely stopped progress and some of us have been busying ourselves building rolling stock of which we will require a lot, all of which will be kit or scratch built because there are little or no proprietary models suitable for running on Clayton.  Clayton is a station on the Queensbury Line which linked the towns of Bradford, Halifax and Keighley.  We have set our model around 1930 by which time the line was operated by the LNER but the traction on the line was still very much ex-GN locomotives that had long since been consigned to secondary duties.    

 

Athough most of my railway modelling is therefore focused on stock for Clayton, my background is very much Great Western and I am a joint owner of the Hungerford Exhibition layout (https://www.shipleymrs.co.uk/hungerford) for which I have been responsible for most of the locomotives.  From time to time I still get  the urge to build something new for Hungerford but it is not appropriate to post my Great Western modelling on the Clayton topic and this new blog will be where I will post such antics in the future. 

 

In addition, and in order to fill gaps in the rolling stock required to be built for Clayton for which no kit exists, it has been necessary for me to learn how to design etched metal kits.  To date I have designed two Howlden coach kits to compliment those already available in the D&S range,   and I have just started the design of my 5th locomotive kit for the LNER J2.  The locomotive kits for Clayton are gradually being made available through London Road Models, my first two - the LNER Q1 and Q2 locomotives are already available, and I have a J7 and a J1 in the pipe line.  This blog is where I will be happy to discuss my approach to etched kit design if anyone wants to ask me questions about the process.  

 

Our model of Clayton has been built on gradients of 1:50 and 1:100 to accurately reproduce those of the prototype and because of this it has been necessary to be creative in the design of the drive systems for our locomotives in order that they have half a chance of hauling prototype length trains up the gradients.  I have therefore designed a drive system that allows me to install the motor in the tender leaving the firebox space for extra ballast.  This system has taken an amount of perfecting but I now have a design that is easily reproduced and seems to work both smoothly and reliably and is still relatively easy to install.  I will pleased to assist anyone wishing to try out this kind of drive system. 

 

FInally in this introduction I would like to explain that I have a particular interest in chassis design.  As a teenager I was fortunate in that Mike Sharman was a friend of my fathers and he taught me his Flexichas apprach to chassis construction.  I have been a convert ever since.  I remain a proponent of compensated chassis construction although in more recent years I have also used the Continuous Springy Beam (CSB) system and use the two systems as I see fit often combining the two approaches in a single model.  I also prefer to avoid installing pick ups on my chassis and adopt the American current collection system for tender engines or split chassis construction for tank engines.  I would like to use this blog to promote these techniques and to assist any modellers who might want to experiment with any or all of these.

 

Regards,

 

Frank Davies

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Whilst I have several on going projects the one I am most involved with at the moment is a new locomotive for Hungerford.  Dapol have recently launched a new model of the Great Western 63xx Mogul the superstructure of which is to a very high standard.  I am planning to design replacement chassis for both locomotive and tender utilising my Motor in Tender drive system.

 

image.png.59b4f50000d7d211f60516883a51e513.png

 

The main criticisms concerning this model have been associated with the look of the slide bars and crossheads as well as various issues with its performance including a lack of traction.  With the exception of the traction issue I can ignore all the others items because of my stated intention to replace the chassis and I will attempt to overcome the traction problems by utilising my motor-in-tender system.    

 

I have already posted a couple of entries on this topic elsewhere on RM Web but have decided to consolidate these and any new entries on this subject here.  The first two posts can be found via the following links:

 

  

 The following is a picture of my  motor-in-tender drive system as used in my GN models.  This system is being modified for the Mogul because the GW 3500 gallon tender has less clearance and so the motor needs to be dropped a few milimetres in order to fit within the area of the water tank.  I will describe this system in more detail in due course under a separate entry.

 

1058752496_Picture5-DriveTrain.jpg.47fd1e94ac5e2f8868bbc60e016d4ccc.jpg

 

I hope you will find this of interest and please ask questions.

 

Regards,

 

Frank

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I thought I'd share some more insights into my motor-in-tender (m-i-t) drive system. 

 

As I have already explained the motivation behind this was to increase the haulage capacity of the models being built for Clayton.  If I remember correctly we were three years into the build of Clayton before we had sufficient track laid to be able to test our models on the 1:50 gradient.  By this time we had also become aware that track radius has as big an influence on haulage as the gradient itself.  The 1:50 gradient on Clayton coincides with a 4ft 6ins radius which is effectively a double whammy.  By now we had built a few locomotives  for the layout and so we could test their haulage ability.  AT this point the tender engines had been built in the traditional manner with their motors in the firebox/boiler.  These loco's started to struggle with anything more than about 17 (random) wagons.  This included a Q2 (0-8-0) which would have seen trains in excess of 30 wagons on the prototype.

 

It was for this reason I investigated the possibility of relocating the motor to the tender.  Initially I talked with people who had done this previously by visiting demonstrators at a couple of model railway exhibitions.  Having been convinced by them that it was possible I next wanted to devise a reusable system that could be implemented across a number of models not all of which would necessarily be built by me.

 

The next key event in this story was my looking at Chris Gibbon's stand at an Expo EM  event where I studied his display of High Level gear boxes and drive systems.  At the time Chris was still displaying his TendeRiser gearbox although it turned out that it was no longer available due to supply issues, but it did give me an idea.  Chris kindly provided me with a selection of gears along with his magic formula for working out how far to space the axles depending upon the number of teeth on any two gears.  The other key item of interest on his display was his RoadRunner Compact+ gearbox.  This is indeed fabulously compact and I realised it could be made to fit entirely within a locomotive's frames, fully concealed under the cab floor.

 

Having sorted out the gear boxes for my system all that remained was to source suitable universal joints for the drive shaft.  People who have done this before had advised me that whilst the joint at the locomotive end of the system needed to accommodate significant amounts of movement the joint at the motor’s end requires very little and a rubber tube is more than adequate.  A tube has the added benefit of preventing the drive shaft dropping to the floor when the tender is separated from the locomotive.  I already had a short length of suitable silicon tube in my spares box and so all I now needed was a universal joint for the other end.  For this I sourced a well-engineered steel ball and brass socket from Markits.

   

The first loco with which I attempted to install this system was my J7. 

IMG_0838.JPG.c6f0b4e3accc11db6abd4c6dcbf2f54b.JPG

For the initial version I used standard 2mm top hat bearings to support the drive shaft.  I had tried to track down 2mm sintered bearings, but I couldn’t find a supplier.  Chris Gibbon had warned me that there could be issues with lubrication on such a system because the shaft would be turning at the same speed as the motor.  This indeed turned out to be the case. Whilst the bearings did need constant lubrication,  it did at least prove the basic concept.    A further refinement was to source some miniature ball bearings to replace the top hat bearings (as can be seen in the above picture).  This has so far proven to be more practical although we will not know for sure until we start exhibiting the layout in anger.  

 

Given that many of the loco's needed for Clayton will require standard GN tenders I have gone to the added trouble of designing tender frames that have the m-i-t gearbox fully integrated (as above).  These frames are a direct replacement for the London Road Model's frames which further simplifies the build.

 

It was now possible to install additional ballast into the space within the firebox/boiler no longer needed to accommodate the motor.  A repeat haulage test using the new drive system has proven the benefit and the somewhat diminutive  J7 demonstrated this by hauling 23 wagons up the gradient.

 

 

I have now retrofitted this system to the Q2 but as yet have not been able to carry out a haulage test on the layout.  

 

This will now be my standard approach to building models for our Clayton layout although where I know the loco is not required to pull full length trains I may revert to installing the motor in the locomotive itself. I have now fitted this system in four of my models including my new J1 kit.  The system is fairly generic although I suspect loco's with large diameter wheels may be more challenging because it will lift the position of the drive shaft above tender footplate level. It is definitely practical for loco's with 5' 2" diameter driving wheels or smaller. 

 

I do have spare etches available for the universal system as illustrated in my introduction to this Topic and if anyone reading this wants to have a go then they should PM me to request an etch and some more details about the additional parts required and where to source them.   

 

Thanks for reading.

 

Frank    

 

   

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I'm a big fan of this method of drive.  I've made a couple of locos like this (J25 and J39), though my efforts are very poorly engineered somewhat Heath Robinson like bodges compared to Frank's superbly constructed examples- but they work, both locos run very nicely!

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Frank, your ideas on chassis design are music to my ears! I have long been a fan of CSBs and the American system for pick-up, but so far haven’t attempted a tender drive. I acquired a couple of Chris Gibbon’s TendeRiser kits some years ago, but so far haven’t managed to resolve the drive satisfactorily, nor managed to accommodate the motor as well as you have - hadn’t thought of putting it at the rear as I thought it would make the drive too complicated. I will be in touch via PM as I’d like to know more about your components.

 

David Murrell

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Perhaps a totally silly suggestion but, looking at the photo's and not having seen the set up in the flesh, would it be possible to turn the loco gearbox upside down and have it slung under the axle for large wheel loco's to keep the shaft under the footplate?

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11 hours ago, Phil Traxson said:

Perhaps a totally silly suggestion but, looking at the photo's and not having seen the set up in the flesh, would it be possible to turn the loco gearbox upside down and have it slung under the axle for large wheel loco's to keep the shaft under the footplate?

Hi Phil,

No not a totally silly suggestion at all.  There is possibly a small range of wheel diameters where it is not possible to run the drive shaft either above the axle (whilst still keeping it below the fall plate) or below the axle placing everything too close to the rail head.  But tonight I've been experimenting in CAD with the D20 locomotive which has a 6' 10" driving wheel and it does look like it could work.  I need to do a more accurate drawing to finalise where to put frame spacers and the draw bar but I'm reasonably confident that it'll work okay.

 

image.png.9275b0245ea3c614ae7abf527cb0ad4d.pngBefore anyone points it out, I'm pretty sure this isn't the correct tender for the D20 but I already had it loaded in CAD so for the sake of a quick experiment I thought I'd use it.

 

Frank

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Hi Michael,

We’ve had this discussion before.  I’ve not had an opportunity to put this to the test because the layout is still not fully operational but on the weekend we did run it fairly continuously last year I was not aware of any problems.  
Time will tell, but it would be easy enough to swap it out if there is a problem.   You’ll have to let me know if you start experiencing issues with this motor.  
Frank

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3 minutes ago, Michael Edge said:

I've got two of them here still running OK, they don't seem to take very much current. I'll put something on here if I get any trouble - I hope not, they are very good motors in every other respect.

Yes I agree with you.  You may recall that when I was experimenting with banking goods trains on Clayton I used my two J7's.  One had the cube motor that you had previously introduced me to at York, and the other had a Faulhaber 1624 coreless motor.  As far as I could determine the two loco's ran identically in every respect.  The cube motor cost less than a tenner and the Faulhaber as a one off purchase from the UK distributor would cost well over £50.  No contest.......

 

Frank   

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37 minutes ago, 57xx said:

Thanks for starting this thread Frank, great info in it already!

That’s very kind of you to say.  
 

I was thinking today about why I felt inspired to start this thread?  I think the overwhelming reason is because I want to use this thread to encourage others to try out techniques which I have gained much pleasure from mastering but which have been discouraged elsewhere on RM Web.  Mastery of such techniques then open up the possibility of migrating to EM or S4 which otherwise might not be a considered option.
 

It’s not that there is anything wrong with modelling in OO, I still do when I work on the club’s Leicester South (GC) layout, but just that if you are going to build everything anyway then why wouldn’t you at least consider a more accurate track gauge?

 

At the same time I hope others who read what I’m doing will offer alternate approaches to achieving the same or better outcomes.  I still want to develop as a modeller and I know I still have things to learn.  
 

Thanks for reading,
 

Frank

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Hi Frank, interesting thread.  I picked up a Bachmann Mogul last year at Wakefield for peanuts, unused but with damaged slidebars one side.  I immediately went round to see Andrew and bought a Comet chassis for loco and tender.  Having seen this thread (and the dicussion we had at Wakefield - last year?) about your tender drive I'm assuming that using the Comet chassis with it would be perfectly OK.  If so, put me down on the list for one as well please!

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Hi Andy,  

I can't see a problem with you using the Comet chassis for the loco but at the moment I do not have the option of just supplying the reduced height motor in tender system required for the Churchward tender without supplying the loco chassis as well because they are on a shared set of etches. 

 

My universal system shown earlier in this thread requires greater clearance e.g. I think it would fit in the Churchward 4000 gallon tender and in most of the GN tenders that I will be building for my Clayton locomotives.  If you are happy to go on that basis then I'll certainly order an extra set of etches for you once I know that I've ironed out any errors in the CAD design.

 

Frank    

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Andy?  Who's Andy?  I know I'm quite 'handy' at railway modelling but I've never been called Andy before!  However, it's one of the nicer things I've been called over the years:)

 

I think a 4000 gallon tender is way to big for a mogul so I might pass for now, thanks all the same.  I'm sure I'll be able to work something out using the Comet etches and a similar method to yours.

 

Or I could just power the loco as 'normal'......................:senile:

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56 minutes ago, 5050 said:

Andy?  Who's Andy?  I know I'm quite 'handy' at railway modelling but I've never been called Andy before!  However, it's one of the nicer things I've been called over the years:)

 

I think a 4000 gallon tender is way to big for a mogul so I might pass for now, thanks all the same.  I'm sure I'll be able to work something out using the Comet etches and a similar method to yours.

 

Or I could just power the loco as 'normal'......................:senile:

Whoops.  No idea who Andy is either. Apologies....  If I decide to produce the new configuration as a universal unit I will no doubt announce it on this thread but it won’t be any time soon as I don’t currently have a personal need for such a unit. 
What I will commit to do is check the suitability of my replacement chassis  for use in the Mainline/Bachman Mogul body.

Frank

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  • 2 weeks later...

I'm not a great lover of having lots of different projects on the go.  Whilst some people seem able to keep multiple projects progressing in parallel I regret I am not one and I'm more productive when I progress one project at a time from start to finish.  Unfortunately of late I appear to have started several projects and I've realised that I'm failing to finish anything and so over Christmas I decided it was time to finish a project or two.

 

One of my Hungerford loco's has long been stood on the shelf above my workbench awaiting attention.  A few years ago I converted a Hornby 28xx to EM to replace my ancient Cotswolds 42xx on the long goods train.  The 42xx is not appropriate for the task but had been the only goods loco powerful enough to pull the freight until the rebuilt 28xx entered service, or at least that had been the plan.  Conversion had taken the form of a replacement chassis.  I seem to recall that this was a Comet chassis but rather than use the white metal cylinder castings I had opted to build the cylinder assembly from a Perseverance GW cylinder etched kit.

996692697_Hornby28xx.jpg.d7f8d5c5a14dade3827083991e82decd.jpgIn practice the 28xx did not live up to expectations.  Not only was it slightly too light with a tendency to slip, although it set off happily enough, as it progressed around the layout it would gradually slow down and by the time it got back to the fiddle yard it would be crawling.  The loco was fitted with a Portescap 1616 unit which had been rebuilt with alternate frames from MJT.

447532036_28xxRejectedMotor.jpg.def6d678d3e37df1b8c7792c1c26e0c6.jpg

This should have been more than capable of performing the job to which it had been allocated but not so in this case.  My suspicion was that the motor was overheating and in doing so was losing power.  The loco ended up staying in my stock box and the 42xx was re-commissioned.

 

More recently I had been very impressed by Chris Gibbon's (High Level Kits) new range of coreless motors and decided to replace the Portescap unit with his 1320 motor coupled to my favourite High Level gearbox - the 40/1 RoadRunner Compact+. 

143517836_28xxWithNewMotorGerbox.jpg.76a851f1ba71480fab1e896e7829032a.jpg

The compact nature of this combination has the benefit of occupying significantly less of the firebox than the previous unit freeing up space for additional lead ballast.  The extra ballast will almost certainly eliminate the slipping previously experienced with this loco on its allocated train.

 

219363986_28xxWithExtraLead.jpg.ee5dcea25ace110c04330bb27375f474.jpg    

The loco has now been reassembled and tested.  It runs smoothly and (virtually) silently from a crawl all the way up to a prototypically high speed.  The motor appears to have significantly more power than can be used by this chassis which will happily spin its wheels despite the additional ballast.  I should probably mention that the front of the tender is heavily ballasted and this weight is delivered to the rear driving wheels via the drawbar.  

 

Hopefully this loco will now be able to perform the role for which it was built and I have the added satisfaction of being able to tick a completed task off my list.

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Having put the 28xx to bed, the next thing to come to the top of the list is an ongoing project to design a replacement chassis for the Bachman C1 Atlantic.  I planned to convert the Atlantic to EM but a colleague of mine had a commission to convert another C1 to S4 and so I agreed to design an etched chassis kit that would allow for both gauges.  The chassis was designed towards the end of 2019 and at the start of 2020 I test built my EM version using the model as sold by Locomotion based upon the preserved C1 on display in the museum.  The chassis went together far better than I could have hoped but I did encounter a couple of problems with my design.  I wasn't happy with the weight distribution and I couldn't get as much ballast as I would have liked over the driven wheels.  In addition I the spring detail that I had designed for the rear outside frames was impossible to actually build. 

 

I therefore modified the design slightly.  In order to allow more ballast over the driven axles I moved the pivot point on the compensation beams over the driven axles so that the pivot was a third of the way along the beam and biased to the rear rather than central.  I also redesigned the construction of the detailing of the outside frames so that it was capable of being built.

 

789131203_C1AwaitingPainting.jpg.eff2410e1f795d625d5eca2ae135264b.jpgIMG_2099.jpg.43e13aa1390a8e458705ded658c6cea6.jpg

 

By the middle of the year I had completed my EM model and it was ready for painting at which point my colleague was ready to start on his S4 conversion. 

 

Whilst there were a couple of minor albeit unexpected  issues with the etches I had supplied him with, the loco's chassis went together successfully but he reported major issues with the tender chassis which I initially found completely bemusing.  Eventually it became evident that the model he was attempting to convert had a different tender to the one I had designed the chassis for.  Not only were the wheelbases different, whilst the tender I had built had the brake hangers to the rear of the wheels, his tender has the hangers in front of the wheels.  

 

Once the problem had been identified I felt I had no option but to modify my design to include the components needed to build this alternate tender chassis.  A 2nd Bachman C1 was purchased and a request for help was sent to Paul Craig with regards to prototype information.  I was advised that a preserved prototype for this alternate tender is attached to the C2 Atlantic  (Henry Oakley) at Locomotion and they were known as 'front enders' because of the unusual brake arrangement.

 

A new set of CAD files were prepared and just before Christmas I received the Nickel Silver etches from PPD Ltd.  I now have to assemble these etches in order to test them and so, as I don't need a 2nd EM Atlantic, for the first (and probably last) time I'm going to build the S4 version just so I can tick an S4 locomotive off my bucket list.  As yet I have no idea if and when I will ever get a chance to run it but hopefully someone will offer me operating rights so I can see if it performs okay.

 

I'm only a couple of days into the build and so this is as far as I've got.  

636964300_C1TenderOnNewWheels.jpg.b136c3838bed49315f20569a0c58241f.jpgCurrent collection will be by the 'American System', whereby the loco's chassis collects current from one rail and the tender's from the other.  To avoid the need for pickups the rims of the plastic centred wheels are shorted to the axle using shorting tags purchased from the EM Gauge Society's stores.

1768085093_ShortingEtch.jpg.cc8f2d34f06a8bfcf8d7a9e7ab4fe4bc.jpgTo install these I grind a small slot in the rim of the wheel with a mini drill, and having trimmed the tag to length I solder the tail of the tag to the rim of the wheel using a very hot soldering iron so that I can get in and out without significantly over heating the rim of the plastic centred wheel.  I've found that if the rim of Alan Gibson's wheels expands too much it becomes loose from the plastic centre.

 

1016128859_GroovedWheel.jpg.cf5a15f107e4c730ed7bacfe765a4e36.jpg1173027487_WheelwithShortingStripFitted.jpg.cffd5d39347923bb6bd54cf65e25d80d.jpg  

I will continue to post progress as I go along over the next few days/weeks.

 

Thanks for reading.

 

Frank

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I would put the motor/gearbox in this way round.

622929665_ScreenShot2021-01-04at08_08_18.png.61d31fe9cebeb9fbd2ba63b48e0c32b7.png

This is a High level gearbox in the ashpan, motor vertical in the firebox leaving all the boiler space available for weight over the driving wheels. Depending on the motor fitted it could be angled back towards the cab to leave even more room for weight. A  Portescap would fit in the same way.

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