Tunnel portal timbers

R

rusty spike

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I’m scratch building a couple of tunnel portals for my 1:20.3 D&RGW line.
please does anyone have information as to the size of the strengthening timbers which run vertically and horizontally which hold the planking in place? I bought 15mm x 15mm but they possibly look too large.
Thanks, Richard
 
Rhinochugger

Rhinochugger

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Well, that would be 12" x 12" which is the sort of timber baulk that was often used beside roadworks - probably a bit hefty.

Have you got a photo - we could have an educated guess ;);)
 
R

rusty spike

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I was basing it on this model, which I haven’t been able to get hold of.
The timbers look a little thin when the photo is enlarged and I think come out around 10mm. (8 scale inches?) However 15mm (12”) seem a tad large. I realise the obvious solution may be something in between, but I would like it to be right if possible:)
 

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Paul2727

Paul2727

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I was basing it on this model, which I haven’t been able to get hold of.
The timbers look a little thin when the photo is enlarged and I think come out around 10mm. (8 scale inches?) However 15mm (12”) seem a tad large. I realise the obvious solution may be something in between, but I would like it to be right if possible:)

Found this on a railroading site, along with the comment "
Some are wood some are rock some are concrete.
Figure 12 x 12 timber and 3 or 4 x 12 planks. "

Seems to be shown in 1:1 measurements. Grid in 1 foot squares. So aperture would be 240 mm high and 180 mm wide. Does that sound right to you?
Hope this helps.
Paul. 1597953972465.png 1597953972465.png
 
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Rhinochugger

Rhinochugger

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Well then, 15mm or 12" x 12" may not be that far out then :nod: :nod:
 
R

rusty spike

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Many thanks for your illustration Paul :)
I can crack on and get building!!
Thanks again, Richard
 
korm kormsen

korm kormsen

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i made my wooden portals with 10 by 10 mm.

here a pic with a Bachmann Big Hauler:

if you are interested in the building pics, here:
 
dunnyrail

dunnyrail

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Thinking this through and noting the possible loads that the real thing would be holding a foot is not that out of the way size wise. Look at the timbers holding up Piers at the sea or river, easily a foot and possibly over.
 
Rhinochugger

Rhinochugger

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Thinking this through and noting the possible loads that the real thing would be holding a foot is not that out of the way size wise. Look at the timbers holding up Piers at the sea or river, easily a foot and possibly over.
Mmmmmmm - different scenario, different loads, different forces - a tunnel portal isn't usually holding up the mountain :think::think:

Having said that, the dimensioned sketch does point towards 12" x 12" timber :nod::nod:
 
David1226

David1226

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This is beginning to sound a bit like a board meeting.

David
 
PhilP

PhilP

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To be serious..
I believe the idea is to hold-back scree, and the odd falling rock? Possibly protect from 'stuff' washed-out from the mountain?? - So it would want to be substantial.

PhilP.
 
John Le Forestier

John Le Forestier

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I model in 1:24 and my tunnel timbers - same design - are 1/2" square. They look fine.
 
Rhinochugger

Rhinochugger

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I model in 1:24 and my tunnel timbers - same design - are 1/2" square. They look fine.

I was tempted to go down the route of suggesting that if it looks right, it is right, but our friend was looking for getting it right, as in I assume accuracy, and he is modelling the D&RGW.

However, the likelihood is that on narrow gauge lines, even the mighty D&RGW may not have had a standard design for this sort of structure, and local variations may have slipped in :think::think:

So, I'm awfully tempted to say, stick with the 15mm timbers 'cos they'll look about right :nod::nod::nod:
 
R

rusty spike

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i made my wooden portals with 10 by 10 mm.

here a pic with a Bachmann Big Hauler:

if you are interested in the building pics, here:
That looks very nice. I don’t know how coffee stirrers would stand up to the great outdoors though?
 
Rhinochugger

Rhinochugger

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That looks very nice. I don’t know how coffee stirrers would stand up to the great outdoors though?
Well, they survive coffee - which is more than the plastic ones used to :devil::devil::devil:
 
korm kormsen

korm kormsen

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That looks very nice. I don’t know how coffee stirrers would stand up to the great outdoors though?

when i was still outdoors, i had coffee-stirrer buildings outside as well.

same as the boards on the 1:1 barn, i built, they were affected by sun, rain, wet, dry, cold and hot.
depending, on the side of a trunk, they were cut from (one can tell by the grain) they tend to bend out or in.
but fixed to lateral "beams" every 1.5 inch or less, they stay fairly straight.
bad news, neither white glue, nor heatgun glue serve, like indoors.
the german UHU and two part epoxies work.
best are mecanical fixes like shoemaker nails (the soft ones) or stapler clamps.


and paint! if you want to guarantee a good warping, paint or varnish just one side of the stirrers.

 
Rhinochugger

Rhinochugger

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Best external wood glue - Titebond II :nod::nod: