Glenmutchkin - Putting a Backbone into a Goods Shed

Tell us about your layout, where you put it, how you built it, how you operate it.
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Mark Tatlow
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Re: Glenmutchkin - First Four Boards Complete

Postby Mark Tatlow » Thu Sep 11, 2014 8:46 am

Will L wrote:As one who isn't that enamoured by the letter box style of layout presentation, I'd haver said "a tad low" was an underestimate. Particularly given the depth of the layout. While I agree it's nice to be able to see trains travelling at eye level, I've always though that this was fine for plain line, preferably on an embankment, but you looses something on a layout with a number of parallel tracks, like at a station, if you can't also enjoy the panoramic view.

But then that's just my personal view, its your train set.


I think the size of the boards (particularly the width) and the height they are presently set is slightly misleading you. The gallows bracket is at 1.9m presently, I had intended it to be about 2m. The underside of those at Portchullin is 1.8m, so only the tallest have to stand back a tad to be able to see the layout - I think I got that about right.
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Re: Glenmutchkin - Baseboards coming along

Postby Mark Tatlow » Fri Apr 24, 2015 8:28 pm

Just prior to Portchullin’s last two exhibitions, Tim of S&T Joinery brought around the last couple of boards so that all of the scenic boards are now back at home. Obviously, this meant that we had to do a test erection!
All boards 1.JPG

All boards 2.JPG

And very pleased I am too, especially with how flat they are. A rear contrast to the rolling hills affect that I managed on Portchullin. I am obviously hoping that this is going to result in much better and more reliable running.

The design of the leg and the supporting beams can now be seen more clearly. it does take a bit of time to get these level (caused I believe by the absence of levelness in S&T’s workshops! However, once the beams were level, it was a matter of moments to place the boards on them and connect them up. So I think we will do some setting out at the weekend.
All boards 8.JPG

Below boards 1.JPG

In some respects the photos don’t quite do justice to these boards and also how large they are collectively. The width in the top view is 1200mm and overall the length of the boards together is 5250mm. As will become apparent in future posts, I am going for the “railway in the landscape” feel and I don’t want it to fee cramped either.

And if anybody wants an electric loft ladder, this is where you go http://www.st-joinery.co.uk/
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TonyMont
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Re: Glenmutchkin - Baseboards Back Home

Postby TonyMont » Sat Apr 25, 2015 8:45 am

Very nice, my boards are nowhere near this level of construction. I can't wait to see the layout develop.

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Re: Glenmutchkin - Baseboards Back Home

Postby Mark Tatlow » Sat May 16, 2015 10:41 am

Definite progress was made with Glenmutchkin over the last 10 days, in that the first portions of trackwork have been laid. At last, it is an embryonic layout!
photo 10compress.JPG
Scrap tank in branch bay


This was started at the two platform faces as in practise this is one of the major setting out points. This is because it is about the only straight bit of track on the layout and also because the platform needs to sit on top of the most substantial baseboard joint on the boards – where the front and back boards abut. The platform will be a separate element of construction and will bolt over the joint, hence hiding it from view.
photo 5compress.JPG


The scrap tak is seen here sitting in the branch bay. The branch bay platform face is to its full length, the main line platform face still needs to continue for 500mm – into the trainshed which presently can only be imagined!
photo 14compress.JPG


Now that the first few bits of track have been laid, a sense of scale starts to become apparent. Not for me the “model to the railway boundary only” approach – I am very definitely attempting to portray the railway in its setting.
photo 3 compresss.JPG


The other major setting out point for the layout is the link into the engine shed; which is a single slip from the main line and a cross-over from the main run-around loop. The baseboard joint is mid-way through the crossover, so deines this end of the layout.
photo 13compress.JPG
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Re: Glenmutchkin - Tracklaying

Postby Mark Tatlow » Sun Sep 06, 2015 9:36 pm

Matters have been progressing with the layout on and off through the summer and a lot more of the track has now been laid. We have both the main line and the full run around loop complete, along with most of the bay and its run around loop too.
photo 2.JPG

The line diverging in the foreground is going into the shed area, those visible below the bridge go to the bay (left) and yard (right). A signalling trackplan can be found on the first page of this thread.
photo 7.JPG

I quite like the sinuousness of the line, which can be seen here/ I have done this in order to give interest to the layoput but it is pretty typical (indeed characteristic) of the lines to the west coast as they wind through the mountainside. I do have in mind some hills to justify this in the finished item.
photo 5.JPG
photo 1.JPG

Already there is a sense of magnitude to the station forming, the platform face (which is not all in view in either of these views, comes in at about 7 feet – enough for an eight coach train of pre-grouping coaching stock. Really, its length is defined by the length of the bay – this will become clearer when the train shed appears because the bay has to start clear of this..
photo 13.JPG
photo 4.JPG
photo 12.JPG

I have also placed into its approximate position the road overbridge that separates the shed from the main station area. The construction of this can be seen in postings here viewtopic.php?f=91&t=1345&start=75. The intention of hte bridge is to act as a scene blocker and thus to compel the watcher to view the layout from more than one location to appreciate it.
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Re: Glenmutchkin - Tracklaying

Postby Terry Bendall » Mon Sep 07, 2015 7:10 am

Looking very impressive Mark. Soon be finished! :D Shall I book you in for 2017 or 2018? :D :D

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Re: Glenmutchkin - Tracklaying

Postby Mark Tatlow » Mon Sep 07, 2015 8:18 am

To avoid disappointment Terry, I would wait a while yet!
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Re: Glenmutchkin - Tracklaying

Postby beachboy » Wed Sep 09, 2015 8:37 am

Hello Mark,

Your layout looks to have the potential to become a masterpiece.
Particularly when viewing the sweeping curves from the layout ends.

When working on the layout, in particular with track work & stock handling. Do you find the width to become a progressive problem with the back & neck ache. Those high embankments cutting into the elbows. Or is the track built offsite.
Also, you seem to have three light sources on the layout, with those ghostly shadows. I trust that's not a problem.

Out of interest, your second pic shows a turnout with partial interlacing. Do you know if that was based on a change in practice from being 10" sleepers throughout, to the introducing 12 / 14" for the doubling of rail chairs per sleeper. Or Bridge chairs even, if used, perhaps later.

Regards, Steve.

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Re: Glenmutchkin - Tracklaying

Postby Mark Tatlow » Wed Sep 09, 2015 11:36 am

Oh, lots of questions!

Yes, the depth of the boards is an issue, but the maximum reach is 24 inches (the board depth is 24 at its most extreme). In an operating situation, it is thus possible to reach items without amazing bother but it does create issues with working on the track (etc) in the centre. For this reason, the whole of the left hand side of the layout is in fact two boards deep, the split being masked by a detachable platform (visible as the plank of wood in the pictures); when split the trackwork can easily be reached. Having said this, neither the front nor the rear ground profile has yet been formed, so it will be cut down quite a lot yet from what you are seeing.

The light sources are not the layout lighting, that issue has yet to be confronted. I have concluded that I will be using strip lights and that there will need to be a strip at the front and a second one part way back to illuminate the rear - the latter at least will need to be shielded to prevent two shadows!

Most of the turnouts are interlaced, although there is some partial interlacing on one and the slip is entirely sleepered with full length sleepers (I just couldn't face trying to do it as an interlaced slip, although I know they did exist!). I do know that it is perfectly proper to have a mixture as I recall finding a partially interlaced turnout in Lairg yard in the late 1970s/early 80s - the crossing tending to get attended to first, as I have depicted.

The use of 10" sleepers meant that they had to be perpendicular to the rails as otherwise the twist that the chairs presented to the sleeper meant that they spilled over the edge of the 10" width. Thus, if you go for full length sleepers you have to have 12" sleepers and if you go for 10" sleepers you have to interlace them in order to maintain the perpendicular angle. I believe that the lack of support that the diverging roads tended to get from the absence of full length timbers led to problems which is why there was a phased replacement of the interlaced turnouts over time.
Last edited by Mark Tatlow on Sun Nov 15, 2015 6:03 pm, edited 1 time in total.
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Re: Glenmutchkin - Tracklaying

Postby Mark Tatlow » Sun Nov 15, 2015 6:02 pm

Testing Times with Terribly Troublesome Turntables

A decade or so ago, I did start a MPD type layout and got some way with the building of a working turntable but had lots of trouble with it and this did rather kill off my enthusiasm for the layout - with inevitable consequences............

The difficulty was to get it to operate smoothly, with any level of reliability, and to stop with sufficient accuracy to enable P4 wheelsets to enter and leave the turntable without derailment. Well, Glenmutchkin needs a turntable, so it is time to confront that particular demon again - and he has not gone away in the meantime! However, I think I have put the blighter back in his box with the help of the Chatham Turntable Drive, a chunk of scratchbuilding and a dose more cussing...........
photo 5 (2).JPG


The Chatham turntable drive is named after its originator and is supplied in the UK by Model Railway Developments - not a great site listing I know, but there is a better Youtube video. The attraction of this particular drive was the mechanical locking arrangement - this means that it both stops consistently and then holds the turntable deck firmly there until activated again. The basis of the drive is a large wheel that has numerous fingers cut into it - the user then takes a finger away for the positions at which it is desired that the turntable will stop. When operated, a plunger runs across the tips of the fingers but where it encounters a gap, the plunger is pulled into the gap and cuts the power at the same time. To operate it again, the plunger is pushed free of the gap by way of a solenoid and the power to the drive reactivated.

The concept is great but there are some issues. The first was that the solenoid did not fully operate when activated. I found two problems with this; the first being that the control box seemed to send a less than full voltage to it. This was fairly easily dealt with by bypassing the control panel with the push button. The second problem related to the microswitch that alternates the power between the solenoid and the drive motor. The spring to this, even though it is quite light, was sufficent to offer to much resistance for the solenoid to overcome. I managed to overcome this by making sure that the rest of the plunger is as smooth as possible by rubbing all the parts down with fine wet and dry and a touch of oil. This takes a degree of care to set up to get the balance right and I am worried that it will be a source of problems for the future but for now it works.
photo 28 (2).JPG


The next issue, is that the motor is not engaged to the drive wheel by a mechanical set of gears and instead has a brass wheel that runs on a rubber rim. This is probably designed as a safety feature to stop the motor burning out when a problem is encountered but it is prone to slipping rather too much. I have sought to overcome this by way of wrapping the motor wheel with sandpaper but this has only been partially successful. There are still more tweeks to do but I have found that it works rather better in one direction than the other, so this may be the ultimate solution!
photo 7.JPG


The next issue was to set the ride height of the turntable deck up correctly. I found that this had two aspects to worry about; the height of the deck relative to the rails that it runs on and then the height of the deck relative to the approach trackwork. I found that it is not sufficient to simply seek to try and get the deck set up correctly with fixed construction - it was simply too sensitive to minor errors. Therefore, I made up a mount with 50mm M4 bolts. By threading on a pair of nuts onto this, it was possible to adjust the exact positioning of the drive relative to the deck and then the entire assembly with the baseboard. The first of these nuts is shown on the above picture and once the drive unit is in place. the second set is tightened from above to hold it all in place. I am concerned, however, that they will loosen over time - so some "nut-tight" has been added to the shopping list!
photo 11.JPG
photo 11.JPG (51.34 KiB) Viewed 6080 times


I connected the shaft of the drive unit onto the turntable deck by way of a small piece of tube. This had grub screw clamps onto the drive unit shaft and a permenantly attached bolt on the top (bottom in the picture). The rod to the base of the turntable deck was reduced in diameter slightly such that it would rock just a touch and take up any inconsistancies in the turntable well. However, I ensured that the bolt was tight in both the rod and tube, so there was limited backlash.
photo 31.JPG


Next up was a turntable well; which was another area where the gremlin made itself felt last time. Most of this had to do with trying to get the turntable deck to sit squarely and equally in the well. As already noted, I adopted the oppisite approach this time and built the well to fit the deck and simply relaid the rail afterwards so that it was exactly above the pivot - it has proved to be a whole lot easier and could have saved a lot of frustration last time!
photo 22.JPG


The well walls were formed of Will random stone sheet, as I did not think that they would have used anything particularly fancy on a turntable well. However, to stop them springing out of the curve, I laminated this with a chunky thickness of plasticard and also secured them to a plasticard base - this also formed the base for the rail, which is secured in turn with Exactoscale chairs. One thing I did notice when studying prototype photos is that the chairs on the turntable rail are quite closely spaced - presumably because a relatively limited number have to support the entire load of the engine (much less in number than in plain track due to the deck carrying the entire weight of the loco onto only four points). I have replicated this on my deck.

The dish to the well was, I have decided, merely ash ballast in the pre-group era (neat concrete was a much more recent approach), so I formed this with Das pressed into place and made as smoth as I could make it with fingers. This never gets crips and "machine made" so represents what I think it will have looked like.

I will look at the deck in the next post, after which hopefully it can be shown fully working and in situ! However, here is a peek:
photo 24.JPG


....alliteration with thanks to Mrs Bennett; I really do remember Magistrate Maskew of Moonfleet Manor........!
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Re: Glenmutchkin - Tracklaying

Postby PeteT » Sun Nov 22, 2015 5:47 pm

Looking good Mark, & thanks for the thorough description of modifications you have made to the drive unit.

With what you currently know, & the bits you think may yet bite in the future, would you currently happily buy another?

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Re: Glenmutchkin - Tracklaying

Postby Mark Tatlow » Sun Nov 22, 2015 6:51 pm

PeteT wrote:Looking good Mark, & thanks for the thorough description of modifications you have made to the drive unit.

With what you currently know, & the bits you think may yet bite in the future, would you currently happily buy another?


I will let you know once I have finished getting it going! Probably, but probably only for a single line in and single line out arrangement.

I was speaking to Hubert Carr about it yesterday and I know he is seeking to deal with a number of these issues, so it may be that some of what I have raised will not reappear when it comes back on the market.

As they say on the TV; to be continued..............!
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Re: Glenmutchkin - Tracklaying

Postby steamraiser » Mon Nov 23, 2015 4:01 pm

Mark,

Are you laying straight to plywood or on to a trackbed?

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Mark Tatlow
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Re: Glenmutchkin - Tracklaying

Postby Mark Tatlow » Mon Nov 23, 2015 4:08 pm

steamraiser wrote:Mark,

Are you laying straight to plywood or on to a trackbed?

Gordon A
Bristol


Straight onto the plywood.

I have decided that the greater likelihood of laying things truly flat (and in this regard, the track really is very good - certainly in comparison with Portchullin!) offset the concern with regard to noise.
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Re: Glenmutchkin - Tracklaying

Postby Mark Tatlow » Sat Dec 05, 2015 12:44 pm

I was going to wait a little longer before doing this post, so that I could show the whole turntable arrangement in place. However, as I am really so bored of the disappointingly nasty debates going on in two other threads, I thought I would post a couple of pictures of modelling - we are after all a modelling society aren't we...........?

Glenmutchkin's shed area is modelled on Kyle of Lochalsh's (it is a mirror image) and I wanted to capture the typically cramped feel of the inspiration. This is the original OS map for the shed (ie old enough to be outside of copyright).

2711.jpg

Key to this is the way that the whole complex centres around the turntable and the first turnout is almost tight against the turntable's wall as this photo extract shows:

Kyle shed extract.JPG
Kyle shed extract.JPG (67.76 KiB) Viewed 5665 times

The first turnout is, you will see, a tandom and whilst it is not visible in this picture, almost certainly it was interlaced (as the Highland always seemed to always use interlaced turnouts). Well, interlacing gets quite crowded on a tandom turnout, as you can see:

photo 2 cropped.JPG

It takes a long time to do all of the sleepers as there are a lot of them but once it is done, it does look rather impressive don't you think?

photo 4 cropped.JPG
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Re: Glenmutchkin - Tracklaying

Postby Philip Hall » Sat Dec 05, 2015 1:02 pm

Mark, as you rightly say, modelling is what we're here for, and so nice to see more of what you're doing!

The interlaced turnout looks very impressive/frightening but from your picture of Kyle it seems that everything apart from the rails was buried in muck, so I wonder why you went to the trouble of interlacing, or indeed, normal sleepers? Do you intend that the sleepers should be a little more visible and well kept?

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Re: Glenmutchkin - Tracklaying

Postby Knuckles » Sat Dec 05, 2015 1:26 pm

Looks awesome. I get a kick out of see8ng good trackwork, then wonder if I'm mad or not.

How do you know if interlaced sleepers or long timbers should be used considering both were used in reality?
I'll need to somehow build a 3 way tandem at some point.
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Re: Glenmutchkin - Tracklaying

Postby Armchair Modeller » Sat Dec 05, 2015 1:54 pm

Mark Tatlow wrote:I was going to wait a little longer before doing this post, so that I could show the whole turntable arrangement in place. However, as I am really so bored of the disappointingly nasty debates going on in two other threads, I thought I would post a couple of pictures of modelling - we are after all a modelling society aren't we...........?


What a good idea! ;)

That looks to be an excellent piece of trackwork, Mark. The layout of the loco shed is interesting. Modellers' logic would have been to run all the roads directly off the turntable and avoid the need for any turnouts in the loco shed area. Presumably, the risk of snow and ice jamming the turntable in such an isolated site made that unrealistic in real life?

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Re: Glenmutchkin - Tracklaying

Postby grovenor-2685 » Sat Dec 05, 2015 2:27 pm

Modellers' logic would have been to run all the roads directly off the turntable and avoid the need for any turnouts in the loco shed area. Presumably, the risk of snow and ice jamming the turntable in such an isolated site made that unrealistic in real life?

And in real life moving the turntable is much more laborious and much slower than changing a point while any cost saving would be negligible.
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Re: Glenmutchkin - Tracklaying

Postby Mark Tatlow » Sat Dec 05, 2015 3:51 pm

grovenor-2685 wrote:
Modellers' logic would have been to run all the roads directly off the turntable and avoid the need for any turnouts in the loco shed area. Presumably, the risk of snow and ice jamming the turntable in such an isolated site made that unrealistic in real life?

And in real life moving the turntable is much more laborious and much slower than changing a point while any cost saving would be negligible.
Regards


Hmm, not sure why they didn't run all the lines off the turntable as this would have reduced the footprint of the shed.

The Kyle extension was famously expensive to build, due largely to the cost of blasting out the hard granite along the line and particularly around the Kyle terminus. So reducing this a little by reducing the footprint of the shed would have been worthwhile and I would think would have produced a saving.

The Highland only ever had one round-house construction and one other turntable that truly acted as a turnout; it seems not to be their mindset. Whilst there was certainly effort in turning a hand turntable, time was hardly a great problem with only a couple of trains a day!!
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Re: Glenmutchkin - Tracklaying

Postby Mark Tatlow » Sat Dec 05, 2015 3:53 pm

Philip Hall wrote: I wonder why you went to the trouble of interlacing, or indeed, normal sleepers? Do you intend that the sleepers should be a little more visible and well kept?

Philip


I did think about it, but the chairs are visible, so I felt that these precipitated the need for proper sleepering. i might regret it when I get to chairing the track!!

Actually I intend to do the trackwork in the shed somewhat "tough". In some areas I will make the sleepers fairly exposed and in other areas very much not so.
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Re: Glenmutchkin - Tracklaying

Postby Andy W » Sat Dec 05, 2015 6:22 pm

[quote="Mark Tatlow"]I am really so bored of the disappointingly nasty debates going on in two other threads, I thought I would post a couple of pictures of modelling -

Absolutely spot on, and your pictures are so refreshing, seeing work like this is what this board is all about. The interlaced turnout is fabulous.
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Re: Glenmutchkin - Tracklaying

Postby CDGFife » Sat Dec 05, 2015 10:46 pm

That's going to be a lot of chairs! But it looks beautiful.

Cheers

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Re: Glenmutchkin - Tracklaying

Postby Craig Warton » Sat Dec 05, 2015 11:48 pm

Mark,

That is pure, glorious chaos! One gets so used to seeing 1950s and later photos and it is easy to forget how different the pre-grouping era was and how quirky some of the companies were (I model the GWR, they have their own things!). I cannot wait to see more of this, it looks great and it is inspiring.

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Re: Glenmutchkin - Tracklaying

Postby John Palmer » Sun Dec 06, 2015 12:58 pm

Very sadly, there seems to be little information readily available about the PW practices of Scottish railway companies, in particular as to timbering of their P&C work. I’m always pleased, therefore, to see how others have gone about representing this, particularly when it come to complex formations.

Mark, I see you’ve managed to use only sleepers all the way through the tandem, and that leads me to wonder how you determined the sleeper positions, as I see some potential problems with the fitting of chairs to this formation were it to be reproduced full size.

I can only speak as to what I’ve learned about North British practice, but I suspect the Highland may have adopted a substantially similar approach to construction of its common crossings as the NBR. Since the block chairs castings incorporated point and splice rail displacements and angles appropriate for particular crossing values, they effectively determined the pitch between each chair, and hence the pitch between sleepers. From prototype observation I deduce that each of the block chairs on a crossing were mounted at a standard pitch of 18” (+/- 1”, according to my measurements).

You can see this constant pitch between block chairs in the attached picture of part of a drawing of NB P&C work obtainable from http://www.oldpway.info/opw_drawings.html#HR_dwgs (thoroughly recommended).
Annotated NB Common Crossing Dwg.jpg

I’ve marked this to show how the angular displacement of the sleepers relative to each other is also applied to the block chairs, suggesting that there is a difference between the set of block chairs for a left hand crossing and that for a right hand. Of course this wouldn’t be necessary if the sleepers/block chairs were laid out parallel to each other through the crossing area, but on the North British at least it appears that all sleepers were laid as nearly as possible at right angles to the stock rail they were supporting.

Here’s the problem I see in chairing your tandem:
Block chairs.jpg

I’m not sure that some of the block chair positions I have overlaid on your photograph can be adequately mounted on the timbers as shown, but in any case there are some significant variations in the pitch between block chairs in both of the crossings shown, which I suspect could not have been accommodated by a standard set of castings.

To develop a design for a 4mm tandem based on North British practice, I took the 18” pitch between block chairs as my starting point for the sleeper positions. It very soon became apparent that this presented major problems: it simply was not possible to position sleepers at the required pitch at all of the crossings if each sleeper was laid at right angles to the stock rail. I was, therefore, relieved to find a picture of a tandem at Helensburgh which indicated that the North British would, in such case, include some crossing timbers in the formation, and seized on this to justify a mix of interlaced sleepers and through timbers in my design, as shown in the attached picture:
NBR tandem in templot.jpg

Hope this may be of some interest, as interlaced timbering of a tandem can be quite a problem.


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