Tunnel Portal Dimensions.

[John Candy]

About to make a pattern/mould to cast four single track tunnel portals for a twin-bore tunnel (to be located where double track mainline passes beneath high-level single track).

Does anyone have a dimensioned drawing of a mainline single track portal, either brick or stone?

I have drawings in old mags. but it will probably take quite a while ferreting about in the (very, very, hot) loft to find them!

Thanks.

John.

[Traininvain]

This is double track but it gives clearances:

http://en.wikipedia.org/wiki/Bramhope_Tunnel

if you know the names of single track ones you may get similar info

Ian

[MikeWilliams]

Single track which comes to mind is Leighton Buzzard (Linslade).  Some mouths were of course massive and several times what was needed for the loading gauge - think of Box or Primrose Hill!

Blaenau Festiniog is a particularly attractive single bore and I'm sure has appeared in a modellers' magazine somewhere.

Mike

[MikeWilliams]

Here's a photo of Blaenau (on the left).
http://www.penmorfa.com/Conwy/five.htm

Mike

[MikeWilliams]

And here's Linslade, a double track tunnel with single either side, but could model one without t'other.  Maybe a bit too grand!

http://www.linsladewoods.org.uk/railway-tunnel

When you decide on the style it should be possible to find dimensions.

Mike

[454]

John,

Look at "Woodhead railway tunnels" in Google pictures.

There was the "modern" double tracker in electric days but better still there were the 2 x separate bore single track tunnels from the steam days. There are plenty of photos of all from many angles. It is probably the most documented tunnel in the UK which gives all three entrances at both ends of the hill. Ex M.S & L Rly & GCR & Ex LNER & Ex BR.

Oh., forgot to mention the single bore Thurgoland tunnels on the same main line on the Yorkshire side.
If you do these John, I might be able to squeeze my yet to be built EM1 through with pantos raised at a future GTG.
Might even request a couple of castings.

Certainly worth a look.

Good hunting.
Dave
454

[John Candy]

Thanks to all who replied.

Will go through my books for some photos of suitable tunnels and start on the patterns when the weather turns wet again.

Meanwhile, am slogging away at producing more turnouts and hope to complete first circuit next week.

John.

[andrewfoster]

Possibly not usable directly, but the MOROP standards (http://www.morop.eu/de/normes/index.html) are a good starting point for setting clearances before you do the architectural part of it, and they can easily be scaled and adjusted for UK use. They appear to be available only in German and French at the moment, though I was able to download them in English quite recently. NEM 102 has been very useful, and I can easily e-mail a copy if would help.

Andrew

[John Candy]

Thank you Andrew, I have downloaded NEM 102.

Almost 50 years since I passed "O-level" German but I still have my dictionary!
Looks to be self-explanatory in any event.

Regards,
John.

[andrewfoster]

And another possibly useful link here, to the Elgin Model Railway Club: http://www.elginmodelrailwayclub.co.uk/advice/dimensions.  It says it's derived from the old BRMSB standards - ancient history now! - but still quite a useful guide.

Talking of tunnels, I'm building a Gauge 1 double deck plate girder bridge on a curve (5 straight box sections with a centre lift-out section).  It's horrible, but it's what the customer wanted...  If anything derails or stalls inside, the only rescue method I can think of is to send a Jack Russell terrier after it.

Andrew

[MikeWilliams]

Not sure if this helps John.  Only thing is I suspect this may be one of the reduced clearance tunnels around Birkenhead and if so its exactly what you DON'T want!  Not sure how to check that.

Mike

[MikeWilliams]

Dimensions may be easier to read on this close-up.

Mike

[John Candy]

Thanks Mike.

I'll see how the dimensions compare with the old BRMSB drawings and the LMS loading gauge diagrams for the various (pre-group) sections.

John.

[Guinness 040]

Hi John
There are minimum dimension requirements for tunnels and parapets as also with minimum loading gauge limits , although no maximum for the above mentioned and tunnel curvature would not be an issue and all minimum requirements apply to overbridges or under.
Peter..............

[John Candy]

Peter,

Thank you for your reply and for the personal email outlining your current development of a range of civil engineering items for the lineside, as well as rolling stock.

I am sure our members will be interested to learn the details, when you are ready to announce them.

Regards,
John.