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 11 hours ago 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!