Glen Ogle

[gtmspyder]

A little more work was done today:

The new Viaduct was marked out on some 4mm MDF.  I have altered the dimensions slightly as I thought the first attempt looked too spindly, even though the piers were way over length and would have been drastically shortened to fit on the baseboard, I felt that the piers were too close to each other.  So I have increased the distance between the piers and increased the thickness of the piers.

This has resulted in an even longer viaduct, and so, to accommodate the viaduct on the layout I have reduced it's length by one arch.

I also found out that the viaduct is very nearly straight in real life, with only a slight curve at it's lower, Lochearnhead end, so the model has been amended accordingly.



The tools used are shown here, with setsquares, steel rules, pencil and a 58mm holesaw.

I selected an arch diameter that scaled to a size that I had a suitable hole saw available, and drew out the full arch on the 4mm MDF.

I then cut the arches with the 58mm hole saw, and then joined the holes with vertical cuts to the bottom of the viaduct piers to produce the arches.


I was able to use my modellers band saw for two arches in each side, but the limited throat depth meant I had to find an alternate method to cut the remainders in each side piece.



To do this, I clamped my jigsaw upside down in the Workmate adjustable bench, and used it like a fret saw.




The deck is again. the 4mm MDF, with only the slightest of curves at one end, I have also cut an exact replica which will strengthen the bottom of the piers.

The piers themselves now have an inner core of 2" X 1"PSE to hold them square and straight.

And here is the part completed new viaduct, there are still additional pier cores to fit, and the lower decking copy to fasten to the pier bottoms.

I am going to have some fun I fear when I start to excavate the blue foam for the viaduct piers.  I think I am going to have to do a wholesale chop of the back scenic'ed section, and then rebuild the scenery between and around the piers.  I am trying to do as much of the scenery as possible in the foam to keep the weight of the sections reasonable.  Normally, I would just fill the areas with Artex plaster, and contour to suit the location

Regards,

BrianT.
 

[petersmith1942]

Brian
you didnt like my earlier comments but, as I said, and your latest pics confirm, the original idea has enough appeal without introduced operating enhancement. The viaduct is great and in due course when sceniced a train traversing the line will be very attractive
Peter Smith

[gtmspyder]

Hello Peter and good morning. ;)

I did not take offence at your earlier post at all, if I post things on this or any other forum, I am giving people the opportunity to comment, and not all the comments necessarily agree with what I have in mind.

As I tried to explain in my answer to your previous comments, I do not go into the minutia at the pre planning stage, ::) it is inevitable that what I produce has many alterations along the way, and this last post I have made, shows further thought processes, and quite possibly, influenced by members comments, that is why I post in such a long winded way.

I think when coming across a subject post that interests one for the first time, it is better to go back to the very first post on that subject by the poster, to see what the thought processes of the poster, ie me, are.  This is in no way a suggestion that whoever is reading my posts, whenever, do not do this, but as I change my mind quite a lot as I progress, some of my posts may not make a lot of sense if read in isolation. ;D

I enjoy this and many other forums that I frequent, from each I learn something, one has never stopped learning, and at 75, I am still as receptive as I ever was.

Please, whoever is out there, make your comments, and I thank you all in advance, whatever the flavour.


Kindest regards, :-* :-* :-*

BrianT.

[gtmspyder]

I've been a little busy on the viaduct today.



I bought some 300gsm card to fill in the arches on the viaduct.  I marked out parallel strips by setting a compass to the required dimension and the striking off an arc from the edge to mark the cut line, then shunting the compass to the arc and striking another arc etc. until I had done as many strips as I could get out of one sheet.



Using a compass in this way allows the dimensions to be easily transferred without having to keep trying to measure on the millimetre scale over and over again with the possible resulting inaccuracy.




I then cut the strips with a Stanley knife against a steel rule.










The strips were glued between the arches using UHU glue.






As I said in an earlier post, more research into the viaduct brought, to light the fact that the curve in the viaduct was no where near as pronounced as I modelled it in my first abortive attempt, and what little curvature there was lay at the lower, or left end as viewed from the road, so this is what the model looks like now.



That's all for tonight folks,

BrianT.

[tedp]

I like the step by step tutorial, Brian - that's what helps other modellers along. It's a great project and a good addition to the growing number of Scottish layouts!

[Hugh Norwood]

I agree, Brian. I have had a viaduct on my "to-do" list from way before Angst was thought about, so it's good to see how you are doing it.
Thank you.

[MickT]

It's coming along very nicely Brian and is much improved from the Mark 1. Perseverence pays dividends!

I echo the comments already made that your step by step tutorial style makes for very interesting reading.

Mick

[gtmspyder]

I have started to get the base boards ready to accept the new viaduct, the first task was to start trimming the blue foam where the viaduct was to be positioned across the base board joint.



Having reduced the foam thickness, the base board formers were in the way, so these were cut back to the foam thickness.



When gluing the foam in place, I temporarily held it with screws to the back board, and these now needed to be removed to allow the cutter to progress.



Then the viaduct could be test fitted in position to see how much of the foam below the piers need to be removed.



before finally being able to rest the viaduct in its position joining up the adjacent two track bed profiles.

[gtmspyder]

Well at last Photo bucket has decided to co-operate and I can post todays progress:-

With the viaduct now ready and able to be to slotted in place, I needed to have the two approach track beds laid along the ledge cut out of the blue foam.

I decided that the track beds, when in position, would initially support the viaduct at each end, until I could split the base boards and do some work  to underneath the viaduct to help support it.  With this in mind, I glued a small section of MDf underneath the ends of the track bed sections to carry the viaduct.



I used a mastic to lay a bed of soft Gunna Nail, one of many nail mastics that when set, will hold large structures in place.



This was worked into the blue mastic to make sure that it had well and truly stuck to the foam, I have found in the past, that just gunning the mastic onto a surface, sometimes does not stick properly if the surface to be stuck together, is just placed upon the top of the mastic and pushed together, so I rub the mastic into the surfaces before bringing them together, and there is no better tool than your digits.  Luckily, this particular mastic is water soluble while soft, and is easily washed off.



The prepared track bed was then dropped into place on the bed of mastic.



And checked for level across its width, and straightness along it's length.





The track beds were made over long, and to fit them between the viaduct and the baseboard end profile boards, a slot was cut through the end profile boards and the track beds poked throughas they were bedded onto the mastic.



The mastic having been checked was left to set.

The two tongues of track-bed protruding through each end of the base board, will be easily picked up at some time in the future, when I finally decide, how I am going to terminate or turn the track at that point.  

I will cut a portal through the end profile boards with a suitable sized hole cutter to accommodate the rolling stock, when I get to this stage of the build.

The viaduct in place after the track bed had set solid.



The scenic support around the viaduct is starting to be built up, between the piers, which will lift out with the viaduct, and around the bottom of the viaduct piers, which is part of the base board proper.



Regards,

BrianT.

[B.Meldon]

This is looking good Brian.

Something to watch out for is a ridge at the joint between the trackbed and the viaduct.

It may be the angle of the photo but it looks like the approach trackbed is on a grade and the viaduct is flat. Unless you bend down the end of the trackbed you may end up with a ridge at the joint that could cause problems later with couplings and even stalling locos.

But as I said it could just be the angle of the photo the approach trackbed could be level like the viaduct.

We use

[Elmgate]

I am going to tread cautiously, as I do not wish to offend....

In Brian's first paragraph he uses the term "ridge" in its correct context. In the last paragraph he speaks of "ridged" supports. However, I guess that this does not mean 'supports with ridges', but actually "rigid" supports, which from the description, serve to ensure the trackbed either side of the joint is kept at the same level, and allows the smooth transitions between level and gradient.

I hope I have correctly interpreted your meaning Brian? I am afraid that spelling and grammar form a significant part of my job, and I find myself "proof-reading" others' work!

Tim

[gtmspyder]

Thank you Brian and Tim.

I knew what you meant Brian and the straight edge was laid across the joint to check that all was well.

Regards,

BrianT.

[gtmspyder]

A start was made on the topography today with various little bits of infill glued in place where gaps had formed where the pieces of foam abutted each other, as I tried to get the most economical use, out of the piece of blue foam at my disposal.

I marked out the widening riverbed with black marker pen  as it collects water from both sides of the rising Glen, with a feed from culverts under the road draining the East side of the Glen, a stream bridged by the viaduct on the West side of the Glen, and run off from the top of the Glen.




I then cut into the base foam with the vibra cutter along both sides of the marked line.




Then cut and lifted the unwanted section out to form the riverbed.



I couldn't resist just laying a couple of lengths of track across the viaduct and placing the railbus and Lilliput 060 with a parcels van on the track.





That's about it for now, I am taking my wife out for a meal to celebrate our fifty fourth wedding anniversary this evening, so no more modelling today.

Regards,

BrianT.

[Hugh Norwood]

... fifty fourth wedding anniversary this evening...

Congratulations!

[gtmspyder]

Thank you Hugh, we had a nice meal with a couple of old friends and pleasant evening in there company.

Regards,

BrianT.