Making a Start - The Peak District Midland / Monsal Dale pre 1903

Help and advice for those starting in, or converting to P4 standards. A place to share modelling as a beginner in P4.
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Le Corbusier
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Re: Making a Start - The Peak District Midland / Monsal Dale pre 1903

Postby Le Corbusier » Fri Oct 04, 2019 6:46 am

Martin Wynne wrote:Contours at 5m spacing (16ft-5in) are available FREE on the modern OS Maps so-called "Standard" base map:

http://osmaps.ordnancesurvey.co.uk/53.24479,-1.73681,18

What's more that map is geo-referenced and available at global zoom level up to 18.

Which means that Templot (also FREE) can make the screenshot for you, and automatically scale the map to the correct size for P4 to act as a background image to your track plan.

cheers,

Martin.


Martin,

Thanks for this .... the georef. map is great and thanks for the run through of options.

What I had settled on as an approach was to prepare my own base map (buildings/landscape and track bed) in Cad and then import this in to templot to set up the track config.

The reason for this is that I need to adapt and foreshorten the survey info to produce a workable layout plan. I can pull into CAD both the historic map from NLS and the contour map.... and then overlay the Midland 'chain' plan .... this then allows me to over-trace and adapt to get the compression needed. At the same time I can draft in detailed plans for the various built features etc etc.

At the relevant stage I can then pull the plan into templot to detail up the track layout details, which I then export as a dwg and insert back onto the base drawing.

I am in the lucky position of having a reasonably sophisticated CAD package ... one which I draft in daily for work and which is pretty much second nature to me .... and I also have a large format (roll feed) dimensionally accurate plotter for printing.

Anyway ... that is currently the plan :thumb
Tim Lee

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Re: Making a Start - The Peak District Midland / Monsal Dale pre 1903

Postby davebradwell » Fri Oct 04, 2019 8:56 pm

Returning briefly to gearbox restraints, I feel that I swept away the torque link rather unfairly and am including here a concept for a rattle-free design.

Scangear018.jpg


The pin-point axle serves as a staybar and can rock freely in the locating holes. Such a bar is traditionally called a pitman in equipment design and the springs just hold everything together so it can be clipped in place. Yes, it takes up more space than the tab but will have applications. Note that the motor weight goes with the springs rather than fights them. It's important that the link is on the centreline - if at the side then the torque reaction will cause the axle to skew and in different directions for forward/reverse. This causes a change in wheelbase which will account for some of the poor running sometimes experienced when the retaining system is not carefully designed.

Matters arising so far: I have installed my tab system in, amongst others, a J72 and a High Level HL 0-4-0ST so refute the claim that it's only for large locos. I can't understand the arrangement you show in your photo WillL, so can't really comment except to say it would appear that the axle is not free to rock without bending or twisting the wire. With these long drive trains it's probably easiest to use a vertical link (perhaps a pitman) to prop up an extreme end. In all the locos I've built I've never had any difficulty fitting the body over the gearbox so adding the link later seems strange.

Finally, WillL, as a professional engineer, retired from the instrument industry where I had design responsibility and the company that paid my wages had enough faith in my design judgement to invest several millions of £ in projects that I led, I think I can decide for myself how far off-centre I can place my tabs. Further, I believe I'm rather better qualified to judge your designs than you are mine. I judge proposals in an impersonal, factual and I hope professional manner in order to encourage further discussion and improvement. You would do well to stop your ill considered sniping and start making constructive suggestions so that we can all move forwards together and improve the models we are building.

Just in case I'm thought of as a pedantic zealot, I have 2 locos where the motor is just left to rattle around inside the body, carefully considered of course, and they run as well as any others. It's all about freedom.

Thank you,

DaveB
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Re: Making a Start - The Peak District Midland / Monsal Dale pre 1903

Postby Le Corbusier » Fri Oct 04, 2019 9:56 pm

davebradwell wrote:Returning briefly to gearbox restraints, I feel that I swept away the torque link rather unfairly and am including here a concept for a rattle-free design.

Scangear018.jpg


The pin-point axle serves as a staybar and can rock freely in the locating holes. Such a bar is traditionally called a pitman in equipment design and the springs just hold everything together so it can be clipped in place. Yes, it takes up more space than the tab but will have applications. Note that the motor weight goes with the springs rather than fights them. It's important that the link is on the centreline - if at the side then the torque reaction will cause the axle to skew and in different directions for forward/reverse. This causes a change in wheelbase which will account for some of the poor running sometimes experienced when the retaining system is not carefully designed.

DaveB


Dave,

Thanks for this ...

A question to make sure I have properly understood ? :?

I can see how the pin-point axle resists turning towards the bracket ... and I assume that it rotates about the point to allow the wheels to move up and down independently as well as together - hope I have that right.

Int the reverse position when the loco is running in reverse is it the springs which are then resisting the horizontal pull ?

In my instance with the low slung gearbox position It should be relatively easy to find a position for your tab solution so at the moment I am favouring this .... do I take it that having the tab on the centre line of the chassis is critical but it can be offset from the axle centre? I will post something when I am a little further on for comment/help/advice. :thumb
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Re: Making a Start - The Peak District Midland / Monsal Dale pre 1903

Postby davebradwell » Sat Oct 05, 2019 1:04 pm

Yes, Tim, the springs are holding it all together and must do so against the force of the torque re-action. This isn't very large, however, especially with the overhanging motor helping the springs. I detect a hint of wariness but I feel it would be safe enough here as the spring force is contained - perhaps they should be "not very light springs". It was a concept for discussion as it hadn't come up - an adjusting screw could be put at one end to tweak the motor angle and the axle shortened greatly. By way of comparison, it wouldn't be wise to spring the tab against one side of the slot on the first scheme as this would cause increased friction.

It would be ok to take an agricultural interpretation of centreline for the tab position. The tab offset is fine with the single stage extender on a Roadrunner+ but if further gear extenders are added it would be better to loosely prop up the end of the motor just because of the overhanging weight - I doubt if the torque reaction is sufficient to overcome gravity in this case anyway, it depends on motor size. On my J72, the cab interior (lower front, rear and floor) is soldered to the chassis and the cab front supports the slot for the gearbox tab. Returning to your question, the strict rule would be that as long as you point the tab at the axle it should work with the tab anywhere - supporting the front of the motor is still using the same tab and slot technique but horizontally so it should work at angles in between. You never know until you've tried it but I haven't. You should avoid a situation where the tab isn't very far from the axle and there is a huge overhang as the leverage will cause friction in the tab and hornblocks which will affect the suspension. You'd know it if you got there.

A difficult question to answer in a way that covers all cases and there's room for much discussion on this topic. However you restrain your gearbox, the tab and slot illustrates the movements required. Most torque schemes are spoilt by attempting to over constrain the gearbox.

Here's the killer - you have soldered all your gearbox extender arms together into one frame, haven't you?

On another topic it's troubling that your crankpin throws differ - did you see the exchange between myself and Julian on a different thread so that you might reduce the chance of a repeat? You might also check that the bushes are concentric about the hole.

DaveB

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Re: Making a Start - The Peak District Midland / Monsal Dale pre 1903

Postby Allan Goodwillie » Sat Oct 05, 2019 4:26 pm

Hi Tim, :)

I know we had a chat over my box of Jigs and it looks as if you have managed to get the jig made without much difficulty, it should ensure that you will get all your wheels with correctly set cranks from now onwards.

The thread Tim is using to make sure his crank throws are all true can be found on my basic loco building thread,
https://www.scalefour.org/forum/viewtopic.php?f=39&t=666

My method of securing motors is also shown here, I like to give the motor and gearbox as much freedom to follow the track and wheels, but within certain parameters so there is no knocking against the loco's interior. In this case it is a Portescap motor. The loop can take different forms and is not over-tight. In this case it is tied together at the top, but loops can be made and secured just on one side as long as they leave enough wriggle room.

https://www.scalefour.org/forum/viewtopic.php?f=39&t=666&start=100

I am sure Dave's solution is probably best as he is a trained engineer and I do have the utmost respect for his workmanship. Remember I am just a jobbing artist and have come to my own methods just through the building of many locomotives and making them work. Remember my thread is intended for someone who may be starting to build a loco for the first time and the jigs etc. are intended to be simple to make and easy to use to get around all the likely problems a starter may come across and not cost a fortune either.

There is nothing too sophisticated in any of my methods.

Allan :)

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Re: Making a Start - The Peak District Midland / Monsal Dale pre 1903

Postby Le Corbusier » Sat Oct 05, 2019 6:14 pm

davebradwell wrote:Here's the killer - you have soldered all your gearbox extender arms together into one frame, haven't you?
DaveB

Actually, because of issues accommodating my battery set up I have reverted to a Road Runner Compact underslung on the axle with the motor pointing pretty much vertically into the fire box. ....- my thinking was that It would be relatively easy to position a tab and frame above the axle in this case but am not sure about the cantilever? I had intended to fix the frame rigid to control the position in the fire box. But it seams to me that there is a danger that the overhang will mean that the tab will be held too tightly against the frame and the friction will impact upon the CSB springing of the driven wheels?
Road Runner compact.jpg

davebradwell wrote:On another topic it's troubling that your crankpin throws differ - did you see the exchange between myself and Julian on a different thread so that you might reduce the chance of a repeat? You might also check that the bushes are concentric about the hole.

DaveB


On the crankpin question ... Allan explained that the Jig was to ensure that all the crankpins were identical in terms of angle ... the throw I think is pretty spot on. When checking my crankpins I found that 4 of the six sat down over the axle part of the gig and dropped into the crankpin bush section easily under self weight with no discernible drag ... the other two dragged slightly on the thread. By using a very gentle tweak, these two then sat down equally smoothly. I assumed that this was the purpose of the jig rather than being a problem?
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Re: Making a Start - The Peak District Midland / Monsal Dale pre 1903

Postby Allan Goodwillie » Sat Oct 05, 2019 6:42 pm

Hi Tim, :)

Yes the whole idea of the jig is that you end up with identical throws and crankpins that are at right angles to the face of the boss. They will not drop down freely unless they are right. It's a go/no go situation and should leave you with no doubt that this aspect is right at this stage. The pin is dropping down vertically into a crankpin bush that is in a fixed distance from the centre of the axle.

Allan :)

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Re: Making a Start - The Peak District Midland / Monsal Dale pre 1903

Postby davebradwell » Sat Oct 05, 2019 8:08 pm

You'll have to solder the bits of the gearbox frame together - once you're sure the angles are correct - or it will jump about. Just put a little tack of solder on one side until you are certain the fit is correct. As for a tab, why not take advantage of Allan Goodwillie's timely appearance and put some bits of wire across the top of the motor - I'm assuming the top of it will be high up but it is rather difficult to guess what the overhang will look like. Once the gearbox is assembled can you lash up a piece of scrap or even wood support just to check free axlebox movement. Side movement is needed but that just means bending the wire a bit wide. The motor is now the tab so the wire should act as a slot. Plan A/1 would be a tab on the cab side of the motor with plan B a horizontal tab underneath - the original scheme laid on its side.

I would make a very minor point to Allan with a reminder of the magical engineering concept of "influence". Your motor is driving a rigid axle so of course it doesn't need to move but it's worth avoiding any "influence" on its preferred position by just giving it a little clearance at the sides of the wire. Your thread's so thorough I'm sure you know what I mean.

I might have been an engineer but they wouldn't let me near their fancy workshop equipment.

DaveB

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Re: Making a Start - The Peak District Midland / Monsal Dale pre 1903

Postby Allan Goodwillie » Sat Oct 05, 2019 8:55 pm

Hi Dave and Tim,

Yes of course I agree. The motor and gearbox floats but in a controlled way. I like to build as exact as is possible, my locomotive mechanisms last a long time, but will eventually wear as well as other parts of the mechanism, at least nowadays we have excellent gearboxes and motors which can give excellent long term running and still keep their relationship intact between gearwheel and motor drive. some may not realise that soldering the sides of these boxes helps fix the relationship - worth pointing out.

I wore out my Studiolith gearboxes first season in my Museum in Melrose - they gave very smooth running but did not have the surfaces needed to avoid deterioration and eventual failure. The Portescaps (the original ones) have proved their worth, but I have built many locos with the multibox variation or Chris's High level products. For those reading this thread, it is always worthwhile consulting Chris when buying a motor and box as he will give good advice as it is not in his interests either to sell something not suitable for the locomotive you are building.

Your comment describing putting the wire over the top of a vertical motor was interesting, I do have one or two that drive with a vertical drive going up through the firebox but they all have had the wire running around the motor on the horizontal and attached somewhere to the chassis. One of the advantages of this sort of arrangement is that it is easy to free the motor and gearbox unit if it is necessary to get the wheels out. Must try your suggestion some time.

The idea occurred to me many years ago when I had to replace all the motors and gears at Melrose and I was playing around with a quick release mechanism.

Allan :)

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Re: Making a Start - The Peak District Midland / Monsal Dale pre 1903

Postby Le Corbusier » Sun Oct 06, 2019 11:01 am

This is the current positioning of the motor within the fire box with the battery position indicated.

Motor.jpg


The motor position should be concealed from view by the ash pan, wheels, frames and springs etc.
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Re: Making a Start - The Peak District Midland / Monsal Dale pre 1903

Postby davebradwell » Mon Oct 07, 2019 11:34 am

Ah, I can't have read things properly as I thought you were driving the rear axle to give maximum space in boiler. I would suggest that your tab could be further from the axle (that is higher) as you've got the cantilever situation here - if it works, however just leave it alone - I've seen tabs as short as this but not with a motor on the end. I suggested the top of the motor as the force on the tab and hornblocks would be less. Do you not need the space under the battery? Remember from my slowly dawning last thread, the tab doesn't have to be vertically above the axle, it just has to point roughly at it. It can go off at 45 deg or 90, or anything. There'd need to be an allowance for rock as you head towards the horizontal, however. I'll admit to never using a vertical motor so have no feel for the situation - they knock out some vital bits of my chassis structure but that's a problem I've created for myself.

We might be confusing each other Allan. My intended suggestion to Tim was to copy your scheme but turned on its end and with added side movement because the axle is sprung. There is the added danger of gravity, though, as the angles as described above aren't quite right. I would certainly support your comments regarding wear and I've never used hornblocks where a curved surface on the axlebox runs in a slot in a piece of frame material - derivatives of the original Flexichas. I use cheeks bearing on the outside of the axlebox. Do you think from your experiences I'm being overcautious? I did once survive a Roy Jackson attack on the subject of bearing surfaces.

DaveB

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Re: Making a Start - The Peak District Midland / Monsal Dale pre 1903

Postby Le Corbusier » Mon Oct 07, 2019 12:39 pm

davebradwell wrote: I would suggest that your tab could be further from the axle (that is higher) as you've got the cantilever situation here - if it works, however just leave it alone - I've seen tabs as short as this but not with a motor on the end. I suggested the top of the motor as the force on the tab and hornblocks would be less. DaveB


My thinking here (which I accept may not be sound) was that with the motor located pretty much vertically, the position/direction of the force will be close to vertical as it comes down through the hinge of the gearbox. As such the lever arm back to the axle will not be particularly large and so the element of cantilever will be relatively modest?


davebradwell wrote: Do you not need the space under the battery? DaveB


Unfortunately yes ... there is an LCU board and the wiring to house here :(

davebradwell wrote: Remember from my slowly dawning last thread, the tab doesn't have to be vertically above the axle, it just has to point roughly at it. It can go off at 45 deg or 90, or anything. There'd need to be an allowance for rock as you head towards the horizontal, however. I'll admit to never using a vertical motor so have no feel for the situation - they knock out some vital bits of my chassis structure but that's a problem I've created for myself.
DaveB


I'm afraid I am a little at sea here :? I must be misunderstanding the rotational impact of the motor particularly under load. The way I understood things would suggest that if the tab and restraining bracket were at 45 degrees then the direction of the force would also be directed at 45 degrees? My reasoning would then suggest that if an appreciable force were to be resisted by the frame then because the tab is rigid it would transfer that force at the 45 degree angle into the axle and therefore the horn blocks? wouldn't that effect the action of the springing potentially pushing the wheel either down into the track or lifting it up off the track depending upon the direction of travel?
45 degree force.jpg
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Re: Making a Start - The Peak District Midland / Monsal Dale pre 1903

Postby davebradwell » Mon Oct 07, 2019 7:09 pm

I'm confusing the issue by my own attempts to generalise and of course there are extremes where side effects creep in. The general principle being used is as shown in the sketch below and I introduced the concept of inclined tabs to tackle the question of how far away from the axle it is possible to stray.


Scangear019.jpg



Certainly as you increase the tab angle away from vertically above the axle then the vertical reaction on the axleboxes increases quite quickly but as the tab gets longer so the force is reduced. There are plenty of successful sprung locos around that use a Portescap in the same way as in Allan's photo and where there would appear to be a significant vertical reaction. If you can't use the perfect alignment then you just have to take a stab at a solution, lash it up and try it. You've come up with a scheme - give it a go. Holding the top of the motor was my best guess - I can't say which compromise will work better.

In an attempt to relate your geometry to something familiar, I checked the offset in my B1 and was staggered to find that the tab is 26 deg off axle centre on 26 mm radius with tab itself still vertical. That's making around 0.4 of the force on the tab push vertically - a frightening thought but it works fine. You had me worried for a while there.

Would drive to the rear axle not give you more space? I can't see that it would help the tab geometry, though.

DaveB
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Re: Making a Start - The Peak District Midland / Monsal Dale pre 1903

Postby Le Corbusier » Tue Oct 08, 2019 7:05 am

So .... this is where I have got to at present. The restraining cradle is soldered to the frames with a wire 'H' hoop positioned to allow the tab to move easily up and down but not horizontally. The tab is soldered to the top face of the gearbox and set perpendicular to the cradle ensuring that it can both rise/fall and rock within the wire hoop. All appears to work as it should and it moves easily within its restraints (no discernible friction) . I wonder if one should lubricate the tab with a dot of clock oil where it passes through the restraint to mitigate against any possible friction under load?

torsion mount - 1.jpg
torsion mount - 2.jpg
torsion mount - 3.jpg

The motor and gearbox fit comfortably within the body and drop out with the hornblocks when the CSBs are removed. The gearbox is lower than I would like below the frames but I think you will struggle to see it. The ashpan/bottom of the fire box covers a large portion and it doesn't drop below this. The wheels/springs will also cover and shield it from view ... but a close up photo might reveal part of the shape floating behind the spokes.
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Re: Making a Start - The Peak District Midland / Monsal Dale pre 1903

Postby davebradwell » Tue Oct 08, 2019 8:32 am

You might end up putting the ends of the cradle - or bridge - inside the frames, especially if you've arranged the platform to sit on top of them for support. Neater, too. You don't want much slop in the slot but you can tweak that anytime. Is it worth tackling the ashpan to confirm motor hidden? Tab lubrication isn't going to be important but mention of "clock oil" fills me with fear after I once tracked down problems in a chassis to what I called quick setting clock oil. Does anybody know what clock oil is? You wouldn't want that stuff in your clock - it came from a reputable purveyor, too.

DaveB

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Re: Making a Start - The Peak District Midland / Monsal Dale pre 1903

Postby Le Corbusier » Tue Oct 08, 2019 10:01 am

davebradwell wrote:You might end up putting the ends of the cradle - or bridge - inside the frames, especially if you've arranged the platform to sit on top of them for support. Neater, too.DaveB


DaveB[/quote]
Hi Dave,

Really appreciate you casting an eye over this as I proceed .... this is what is so excellent about the forum and it is so kind of people with more experience taking the time to help/advise.

The 'bridge' occurs at a cut out within the footplate. I positioned it on the outside as it is hidden within the side tanks and I wanted it well away from the CSBs. Is there any reason apart from neatness why it can't remain in this position?

trial mount of shassis to foot plate - 2.jpg


davebradwell wrote:You don't want much slop in the slot but you can tweak that anytime.DaveB


Do I take it from this observation that from the photo you feel the tab might be a little loose? There is very little discernible movement horizontally and I was concerned not to trap the tab effecting the up and down/rocking movement .... maybe I am being too cautious and I can re-set such that it is pretty much touching?

davebradwell wrote:Is it worth tackling the ashpan to confirm motor hidden? DaveB


I am in the process of doing this .... I am making up the ashpan and springs as a sub assembly bolted to the spacer to allow removal. The asshpan covers the lion's share of the box, but there is a section which will emerge set behind the springs and wheel spokes - pretty much as indeicated on the diagram. You will see a sliver of the blue portion where it is visible below the frames.

Motor.jpg


davebradwell wrote:Tab lubrication isn't going to be important but mention of "clock oil" fills me with fear after I once tracked down problems in a chassis to what I called quick setting clock oil. Does anybody know what clock oil is? You wouldn't want that stuff in your clock - it came from a reputable purveyor, too.DaveB


The clock oil I have (but have not used on this build) is from Eileen's. It was recommended as I recall in Iain Rice's book on chassis building - to date I have experienced no issues with 'setting'. What do you use to lubricate axles, coupling rods and the like ... I have even been want to place a drop on the bearings of motors when running them in (following the 'Rice' method ) :?
https://eileensemporium.com/index.php?option=com_hikashop&ctrl=product&task=show&cid=1139&name=superfine-clock-oil-bottle-15ml&Itemid=189&category_pathway=1109
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Re: Making a Start - The Peak District Midland / Monsal Dale pre 1903

Postby davebradwell » Tue Oct 08, 2019 10:18 am

I can't help with lubricants as we avoided them at work - there was a danger that any vapour could be detected by the instrument itself. I acquired a tube of MTS2000 graphited grease (direct equivalent not now available in sensible quantities) which is good for crankpins and motion and I have some model oil which is reputed to be plastic safe. I used car engine oil on axleboxes until my wheels started falling off. There you are, the basis for discussion - there was an MRJ article years back.

DaveB

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Re: Making a Start - The Peak District Midland / Monsal Dale pre 1903

Postby petermeyer » Tue Oct 08, 2019 5:15 pm

What you have built does not match the drawing in that the gearbox sides are now much lower than the axle centrelines. I would question whether this leaves sufficient clearance over pointwork. You can guess how I discovered this kind of problem using an underslung gearbox with relatively small wheels!

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Re: Making a Start - The Peak District Midland / Monsal Dale pre 1903

Postby Le Corbusier » Tue Oct 08, 2019 5:22 pm

petermeyer wrote:What you have built does not match the drawing in that the gearbox sides are now much lower than the axle centrelines. I would question whether this leaves sufficient clearance over pointwork. You can guess how I discovered this kind of problem using an underslung gearbox with relatively small wheels!


I see what you mean .... I will check ...thanks Pete. - This might have been what Dave was hinting at as well :?
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Re: Making a Start - The Peak District Midland / Monsal Dale pre 1903

Postby Le Corbusier » Thu Oct 10, 2019 7:30 am

petermeyer wrote:
What you have built does not match the drawing in that the gearbox sides are now much lower than the axle centrelines. I would question whether this leaves sufficient clearance over pointwork. You can guess how I discovered this kind of problem using an underslung gearbox with relatively small wheels!
pete


Have now relocated the bridge to bring the motor up higher between the frames ... now completely hidden in the ashpan and no danger of clearance issues :thumb

davebradwell wrote:You might end up putting the ends of the cradle - or bridge - inside the frames, especially if you've arranged the platform to sit on top of them for support. Neater, too.
DaveB


So ... right again :thumb ....No problem with the platform, but in my location it sits behind the wheels .... on the one hand great as this ensures that the cradle is hidden ... on the other not so great as looking at it (not mounted these wheels yet) I am pretty certain it will catch on the back of the wheels :? so time to adjust and move again :D

Will load a picture once complete ;)
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Re: Making a Start - The Peak District Midland / Monsal Dale pre 1903

Postby Allan Goodwillie » Thu Oct 10, 2019 10:09 am

Hi Tim, :)

this is all good as it is showing a number of elements that have to find an equilibrium, because there are probably several ways to do anything all of which may give problems or possibilities. If you have a scale drawing it is possible to use a transparent version of the drawings of engine and motor combinations that you can get from High Level - it can be downloaded from the High Level site. You probably have one, but I am mentioning it here as there will be others who are reading this, ( I have mentioned your thread to my Starters Group members as a good example of building a railway from scratch and finding the problems and working them through in the open with other members of the Society helping and giving useful information along the road.)

I use the device these days to save me time when building a new locomotive - it will not tell you everything you need to know however, but you will quickly be able to see things like whether the gearbox will be visible under the ashpan, or whether the brake rods or supports will get in the way, etc. However you are exploring around the possibilities at the moment, and like Julian I am sure what you end up with will be very successful, it is also giving you experience and it is not time wasted, trying these things out, there is no substitute for experience, good or bad, that is how things are learned and sometimes discovered.

Allan :)

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Re: Making a Start - The Peak District Midland / Monsal Dale pre 1903

Postby Le Corbusier » Thu Oct 10, 2019 10:53 am

Thanks for the pep talk Allan .... I am thoroughly enjoying the process so far :D

As Pete pointed out, if I had actually located the motor according to my drawing (using the high-level drawing ;) ) I would have been ok.

I am making my own shorthand notes of all the little mistakes/learning curves as I go on .... to serve as a crib sheet for future builds ;)

The great thing about posting things - warts and all - as I go along ,is people jumping in with comments and highlighting things to think about/adjustments which might need to be made etc etc. As you say there are most likely up-teen different solutions to each problem ... but this represents the way I am choosing to pick my way through - at least with the current build.

If other beginners are also benefitting from the process then that is great. :thumb
Tim Lee

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Le Corbusier
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Re: Making a Start - The Peak District Midland / Monsal Dale pre 1903

Postby Le Corbusier » Fri Oct 11, 2019 2:05 pm

I've been doing a little research into the cab interior ... specifically trying to work out what happens either side of the back head and what covers the wheels. I have obtained these images of the preserved 41708 ... though this has been converted to belpair.

41708 - cab details 2.jpg


41708 - cab details 4.jpg


41708 - cab details 6.jpg


41708 - cab details 10.jpg


Interestingly, it appears that the side without the reverser lever has a riveted casing and wooden lid ... which i assume can be lifted off to gain access to storage beneath. The question then is ... is this a later addition and specific to this loco, or is it standard? This picture from 1905 appears to suggest that it may have been original.... It seems to me that in the background you can make out a similar boxing.

1347 - cab detail.jpg


Another thing of interest is the penetration of what I assume are the tanks into the cab and the rounded nature of the tops. Again this detail would appear to be standard whether we are talking about the original round fire box or the belpair ....

Finally I now have the detail for the coal hole to the bunker which needs to be put in ....

41708 - cab details 1.jpg


So a bit of fun to be had fabricating all of this up! :D
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Tim Lee


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Allan Goodwillie
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Re: Making a Start - The Peak District Midland / Monsal Dale pre 1903

Postby Allan Goodwillie » Mon Oct 21, 2019 2:08 pm

Hi Tim, :)

This is one of these locos which all the extra work onside the cab will pay off as it is such an open cab - quite a lot of work and time will go into this I am sure. I remember the amount of time I put into my first engines - and still do occasionally. Looking forward to this - my own locos for the Wemyss project will use some modified backheads etc. as it is unlikely if anyone will ever have a look in except on the forum as there will be a limit to what will be visible.

Allan :)


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