The Broc Branch in Om scale - an ambitious project that stalled for a decade but is now reawakening

[Mol_PMB]

14 hours ago, PaulRhB said:

Your solution sounds good but a backup would be to build it around a Perspex box tube inset in 10mm from the sides so it doesn’t reflect light but sits hidden in the shadows. 
 

Thanks Paul, that's a good idea. I had considered a perspex box but discounted it owing to the reflections, but your idea of making it narrower and hiding it in the shadows is a good one.

I'll see what the costs for the metal version come out like...

[Mol_PMB]

A few photos of progress at the forest end of the layout. There's still a lot more to do including all the finer details, but it's starting to look the part.

 

Left to right around the end of the room:

 

Here's a closeup of the trees where they're closest to the track. More undergrowth is needed here, but I'm quite pleased with how the layers of trees have worked out:

 

All these photos are from the small stepladder, i.e. a higher viewing position than normal.

 

Next steps include:

- paint the track red-brown and glue it down

- create the level crossing for the lane into the forest

- ballasting

- more fences and fence details

- more trees

- more grass

- meadow flowers and weeds

- forest undergrowth

- make and fit overhead catenary masts and wires

 

That's quite a few weeks work, before I can start on the road and the fields in the foreground.

 

In parallel I've finished the drawings for the big viaduct and am hoping to get the parts laser-cut from stainless steel next week.

Once I've fettled them to fit together nicely, they can go to Boston Lodge for TIG welding by a friendly Bob.

There will be more to do on the bridge span including track, walkways, handrails, catenary in due course.

 

Mol

 

[Mol_PMB]

Having done some pruning and tidying in the garden, I'm on a slight diversion to make some log loads for wagons.

The GFM carried a significant local traffic in logs for firewood, including on the Broc Branch, where logs were loaded at Les Marches, Broc-Village and Broc-Fabrique.

 

This 1943 Swisstopo aerial view shows logs being loaded at Broc-Village, with bogie flat wagons and high-sided 4-wheel opens in use:

The logs were cut into 1 metre lengths and stacked transversely in two rows, with a small gap in between, as can be seen on the left-hand bogie wagon (the other one is still empty). This image from polier.ch shows the loading method more clearly, albeit on an MOB flat wagon:

Here's a GFM example in colour from the 1970s, but not quite so clear:

 

What this means is that I need a LOT of 22.2mm lengths of wood in a fairly random selection of diameters. I've found whilst cutting back some tree heathers in my garden that they provide a very good raw material for these logs, and just need cutting to length, which I do by hand with a piercing saw. It's one of those jobs you have to be in the right mood for! Anyway, here's the result of about an hour's work and I can see it's going to take a few more hours to load my bogie flat!

 

Why is that standard gauge open lurking the background of the photo? Well, they were used to carry logs too. Here's a 1981 Swisstopo aerial view again showing logs being loaded at Broc-Village, but this time the wagon is a standard-gauge 4-wheel open on one of the longer transporter wagons. The logs are being stacked in the same way, two rows with a gap in the middle, and they've filled one end but not completed the other end yet:

Although the standard gauge wagon is about the same volume as the narrow-gauge one, I can probably get away with just a couple of layers of logs on top of a plain wood former, so it may be slightly quicker to make a load for it.

 

Timber traffic on the GFM survived into the TPF era, in the form of larger logs from Montbovon to Bulle. Here are a couple of photos I took in 2012 when I was lucky enough to catch what was by then a very rare move:

 

 

Typing this has given my fingers a break from sawing, so I'd better get back to it!

[Mol_PMB]

As a postscript to my previous post, here's another old postcard of Broc-Fabrique that I've recently acquired. The card was posted in 1927 so the image probably dates from the 1920s. There are many large logs visible in the foreground, waiting to be loaded onto wagons.

Some of the older photos of GFM trains show large logs like these carried longitudinally on the bogie flat wagons - they would certainly be a lot easier to model but in my early 1980s period the log traffic all seems to have been in 1m lengths!

 

Here's another view of the log wagon I photosgraphed in 2012, ready to be transferred from metre gauge to standard gauge at Bulle. The other wagons behind have come from the chocolate factory, including a sugar hopper:

[MOB 2002]

Loving the attention to detail. The log loading seems like the opposite of what you’d see on the RhB, well done for not taking the easy way out.

 

Mark

[Mol_PMB]

I am continuing to cut up logs, but something more exciting happened this afternoon. My laser-cutting order arrived, 18 parts cut from 1.5mm 316 stainless steel.

 

17 of the pieces fit together to make the big viaduct span. I could have done with the assistance of a pet octopus but I got all the bits interlocked together eventually!

This is a dry assembly upside-down:

 

I wrapped some parcel tape around it to hold it together and then took a few photos of it in situ:

 

 

 

 

 

The next stage is for it to go to Boston Lodge for welding - there are 52 TIG welds needed on the top and bottom faces only.

 

There will be a lot more detail added eventually, but for now I'm very pleased that the parts fitted together well and the span captures the appearance of the prototype whilst being quite strong.

 

I had one more part laser-cut at the same time, a tracklaying template to set an accurate 1 metre radius. This will help me lay the curves accurately and avoid tight spots:

 

[7mmin7foot]

Wow, that's some spectacular  model engineering.

It will be a superb structure when completed. Most impressive !

 

Steve

[Mol_PMB]

4 minutes ago, 7mmin7foot said:

Wow, that's some spectacular  model engineering.

It will be a superb structure when completed. Most impressive !

 

Steve

Thanks Steve!

 

After agonising for years about how to make the bridge, it turned out to be quite easy in the end. A bit of design and CAD work with advice from friends about tolerances, upload the drawings and within 5 days the parts were delivered. The cost was about £250 including delivery and VAT, so not cheap but not nearly as bad as it might have been. To that I'll need to add the cost of bribing a friend with TIG welding skills to stick it together.

 

The viaduct is a key part of the layout: by far the biggest structure on the Broc branch, it's the first thing you see as you walk through the door, and it's at eye level, so it needs to be good for that 'wow' moment. The real thing has 3 spans and I only have room for one, but even so it's 3'6" long and quite dominant.

 

Cheers,

Mol

[7mmin7foot]

9 minutes ago, Mol_PMB said:

Thanks Steve!

 

After agonising for years about how to make the bridge, it turned out to be quite easy in the end. A bit of design and CAD work with advice from friends about tolerances, upload the drawings and within 5 days the parts were delivered. The cost was about £250 including delivery and VAT, so not cheap but not nearly as bad as it might have been. To that I'll need to add the cost of bribing a friend with TIG welding skills to stick it together.

 

The viaduct is a key part of the layout: by far the biggest structure on the Broc branch, it's the first thing you see as you walk through the door, and it's at eye level, so it needs to be good for that 'wow' moment. The real thing has 3 spans and I only have room for one, but even so it's 3'6" long and quite dominant.

 

Cheers,

Mol

 

Mol,

In O Gauge, that's not overly expensive in my view,, and made of metal ( stainless steel) too !

For something that is so impressive ( wow factor tick) and unique to your layout, based on the real thing.

It will be spectacular matey... 

 

Steve

Edited May 3 by 7mmin7foot
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[ruggedpeak]

The bridge is amazing piece of work. Must be scope to sell a kit or the design!

[PaulRhB]

The bridge looks superb and more to the point should be resistant to knocks far more than a plastic one of any internal design! 

[Frutigen]

How much does the bridge weigh?

[Mol_PMB]

8 minutes ago, Frutigen said:

How much does the bridge weigh?

Good question, so I’ve just weighed it. 
2.3kg at present.

It will increase when more details, track etc are added. 

[Daddyman]

Nice project. Nice execution. 

[Mol_PMB]

An update on the log loads which are now complete for the two different wagons. Both seen here on the new bit of the layout where tracklaying is progressing slowly but nearly ready for ballasting. A job to be tackled soon is the overhead line masts to replace those galvanised coach bolts.

 

The metre gauge bogie flat:

 

The standard gauge open wagon on transporter:

 

And them both posed in a train with some appropriate motive power:

While I have several drawbars for the transporter wagons, I couldn't actually find one for the photo. They must be in a 'safe place'.

 

Here's a train of empties at about the same location in reality, from polier.ch and the Tram Club Basel archive:

 

 

[Mol_PMB]

I've done some ballasting, which I actually quite enjoy. Unfortunately I ran out of ballast after doing about 2 metres, so I've had to order some more.

Here are the ballast hoppers posed on the newly ballasted section. That yellow one badly needs a repaint - it's far too garish!

This is from normal viewing height:

 

And this from above showing how the field isn't as big as it looks!

 

A couple of views looking along the track from the cutting at Les Marches which was done a decade ago, and leading onto the new section. Now that the ballast is done, I can complete the grass and weeds in the cess.

This overhead mast was the last one I made a decade ago. I need to set up a production line for the next dozen or so that will go around the curve.

The track may benefit from a bit of toning down with red-brown from the airbrush, though the real thing was fairly clean so I don't want to overdo it.

 

 

I'm out and about quite a lot in the next month, so progress may be slow.

[7mmin7foot]

2 hours ago, Mol_PMB said:

I've done some ballasting, which I actually quite enjoy. Unfortunately I ran out of ballast after doing about 2 metres, so I've had to order some more.

Looking fab Mol,

 

Ballasting - My pet hate , out of all the tasks on a model railway layout, its the one thing I'd rather 'outsource' ! Never liked or enjoyed it... but appreciate the end result... not the journey.

Just started this 'chore' on mine.. 4 hours laying the stuff on about 8 foot of track...and still no where near completed.

I do agree though, it instantly changes the appearance of the track and the scenery, just a pain in the  *** doing it !

 

On the upside... O is a little easier than HO ever was, and warmer weather will dry it nicely...   ;-)

 

Steve

 

[Mol_PMB]

5 minutes ago, 7mmin7foot said:

Looking fab Mol,

 

Ballasting - My pet hate , out of all the tasks on a model railway layout, its the one thing I'd rather 'outsource' ! Never liked or enjoyed it... but appreciate the end result... not the journey.

Just started this 'chore' on mine.. 4 hours laying the stuff on about 8 foot of track...and still no where near completed.

I do agree though, it instantly changes the appearance of the track and the scenery, just a pain in the  *** doing it !

 

On the upside... O is a little easier than HO ever was, and warmer weather will dry it nicely...   ;-)

 

Steve

 

Thanks Steve! I find it quite therapeutic  spreading the ballast, but I appreciate we all enjoy different aspects. 

I use a spoon to apply about the right amount of dry ballast each side of the rails and between them, and then flat brushes about 10mm and 20mm wide to spread and level it. Add a bit more with the spoon where needed. 

Once I’m happy, then I spray a mist of water-and-washing-up-liquid using the airbrush. I do this from a distance so it doesn’t blast the ballast away, and keep going until the ballast is all damp. 

Then I make a fairly strong milky mix of PVA and water with a drop of washing up liquid, and use an eye dropper to apply it to the rails and sleepers, taking my time so that by capillary action it spreads through the damp ballast of its own accord. This can be done with almost no disturbance of the grains. 
 

After a couple of days it is all solid. 
 

[7mmin7foot]

Thanks, your airbrush technique is quite refined compared to a spray bottle..

I have had some  movement of the ballast grains..but luckily used a very fine spray bottle... not as fine as an airbrush tho!

Funny, how its a marmite sort of thing.. ballasting...  ;o)

 

Steve

[Mol_PMB]

I just bought this late 1970s slide on ebay showing the GFM's inspection car Dm21 with a lightweight tower wagon in tow.

Quite delightful and begging to be modelled, but I mustn't get distracted. I need to build some overheads first!

 

[Mol_PMB]

I've been away a fair bit recently, and bogged down with house and garden chores, but I have a weekend free to do some modelling.

I decided to build some overhead masts, so I'd updated the drawing and printed it out full size.

I also searched through my stocks of brass section for the required thick-walled tube, M4 studding and 2mm T-section, which make up the mast structure.

I had also located the box marked 'catenary masts' that had been untouched for over a decade. In it, I was hoping to find the jig for bending the T-section, and the beads that I use for insulators. Fortunately, they were present in the box:

 

What I had not expected to find was a collection of 6 nearly-complete masts! I had completely forgotten that I'd made these:

 

So that's a very good start. For the scenic section I'm building at the moment, I need 8 masts and some of these will be suitable. Others need to be of different styles or dimensions so I still have some making to do.

 

Hopefully by the end of the weekend I can show the new batch of masts, complete and in primer.

Then before long my model of 111 can have some wires to reach for, just like the real thing:

 

 

[Mol_PMB]

Well I have made good progress on my weekend project, although not quite as far as I had hoped.

 

Of the six masts I'd made a decade ago, I have used three with some modifications, and the other three are still in the box and will no doubt be suitable for another part of the layout.

I have also made six brand new masts, so with the three old ones I have nine to fit around the curve. They are all subtly different.

The soldered construction is complete, so they are ready for painting and then I can add the insulators etc afterwards.

 

 

One of them is not quite finished; this is the most complex one which is a tensioning mast. I've made one of these already and it's fitted to the layout, here:

 

In making the new one, I've done all the 'normal' bits and some of the extra hooks and brackets for the tensioning. Then I came to fit the Sommerfelt moulding for the tensioning weights, and it was far too small. After some puzzling I remembered that I had this problem last time, and solved it by scratchbuilding the column of weights. This was another soldered construction, hollow for a spring to fit inside. I've run out of time this evening to make that, so it can be a job for tomorrow. So the new tensioning mast needs a bit more work, and then I'll paint them all.

 

For reference, here's the real tensioning mast:

 

[7mmin7foot]

Well have to say Paul, they look fabulous and every bit as  good, if not better than the Sommerfeldt masts!

Very impressed with your soldering and modelling skills mate, well done  👍

 

Steve

 

[Mol_PMB]

7 minutes ago, 7mmin7foot said:

Well have to say Paul, they look fabulous and every bit as  good, if not better than the Sommerfeldt masts!

Very impressed with your soldering and modelling skills mate, well done  👍

 

Steve

 

Thanks Steve! I'd happily use the Sommerfeldt masts if they made the right type in O scale. The nearest they do is this one:

The GFM and MOB both used a very characteristic arched arm on a wooden pole, which I wanted to replicate.

Having worked out a process to batch-build them reasonably quickly, there is the added benefit that the home-made ones are cheaper! The time taken to make them is a very small fraction of the total time to do baseboards, track, scenery etc.

 

I do use the Sommerfeldt wires, both the complete catenary sections and the plain straight wire which finds all sorts of uses in my modelling.

 

When I come to model Broc-Fabrique and Bulle I will need some 'steel' masts, a mix of H-section and lattice types. Again, the Sommerfeldt range in O scale is quite limited and I'll probably end up making my own.

I'll likely use a custom etch for the lattice masts like this one, and the H section masts are easy from brass H section:

 

 

[7mmin7foot]

I should think there is a large amount of self satisfaction building them yourself, and unique too as not commercially available!

It's all looking really good! 👍

 

Steve