Jump to content
Ron Heggs

Points Bridge, Hagg Bank, Wylam, Northumberland

Recommended Posts

This is going to be some impressive structure. Is it all from plastic card?

Share this post


Link to post
Share on other sites

This is going to be some impressive structure. Is it all from plastic card?

Hi, Peter

 

As with all my other structures it will be a completely plastic card/strip build

 

Cheers

 

Ron

Share this post


Link to post
Share on other sites

Ron,

 

I cannot recall another example of a modeller designing & building his own test equipment from plastikard! I hope you enjoyed the cider afterward!

 

Regs

 

Ian

Share this post


Link to post
Share on other sites

Ron,

 

I cannot recall another example of a modeller designing & building his own test equipment from plastikard! I hope you enjoyed the cider afterward!

 

Regs

 

Ian

Hi, Ian

 

Thanks for your comments - I enjoy cider at any time (pity I can't get Scrumpy here in Spain)

 

As the structure is an all-styrene build the test apparatus and test sample had to be styrene - although the test load was inevitably going to be cans of an alcoholic beverage (known mass, easy to fix or stack, and enjoyable refreshment)

 

:drink_mini:

 

Ron

  • Like 1

Share this post


Link to post
Share on other sites

Construction of the lower arch has started -

 

The outer members being 3.2mm Channel facing inward joined internally by a 20thou x 9mm wide strip - making up the 10mm overall width. The end outer plating is 20thou plasticard

 

post-10633-0-87583400-1333189489_thumb.jpg

 

The board is 6mm ply and the pins are 25mm galvanised (that is the reason for the pin hammer)

 

The pins are there only to keep the assembly in place whilst the plasticweld joints set. The plastic strips are pre-curved by finger & thumb and left for a few minutes to ensure any stresses settle out, and won't cause any future warping of the structure

 

- more later tonight

  • Like 5

Share this post


Link to post
Share on other sites

Something tells me you've knocked the odd bottle of solvent over in your time Ron ;)

Share this post


Link to post
Share on other sites

Tie braces between top and bottom arch members fitted to one side only -

 

post-10633-0-95751800-1333228908_thumb.jpg

 

post-10633-0-88611600-1333228932_thumb.jpg

 

Small cross-braces being fitted to top of lower part of arch -

 

post-10633-0-00401200-1333228974_thumb.jpg

 

post-10633-0-69346500-1333229007_thumb.jpg

  • Like 4

Share this post


Link to post
Share on other sites

Photo of the bridge showing the scope of the structure and bracings, etc. -

 

post-10633-0-57219200-1333230014_thumb.jpg

  • Like 1

Share this post


Link to post
Share on other sites

Hi Ron,

 

Was wondering why nothing had been put onto your Manchester Central & Castlefields Viaducts thread recently, then I see you doing this one. Looks like you have made a good start (no surprise there) and will keep an eye on it as it progresses.

 

Colin

Share this post


Link to post
Share on other sites

Hi Ron,

 

Was wondering why nothing had been put onto your Manchester Central & Castlefields Viaducts thread recently, then I see you doing this one. Looks like you have made a good start (no surprise there) and will keep an eye on it as it progresses.

 

Colin

Hi, Colin

 

I see you found my latest project

 

Still making the 119 transverse beams for the Train Shed roof - No point in posting pictures of these until the last 7 bays are being put together with the completed spans

 

Ron

Share this post


Link to post
Share on other sites

Pictures to show progress - just half the arch completed -

 

post-10633-0-84084400-1333470253_thumb.jpg

 

post-10633-0-04130700-1333470277_thumb.jpg

 

post-10633-0-05832900-1333470314_thumb.jpg

 

Fixing the bracings inside the channels was a challenge - until I started using a scrap of 40thou plastic strip to support the brace whilst placing and fixing it

  • Like 4

Share this post


Link to post
Share on other sites

- latest photos of progress -

 

The lower arch cross-bracings completed -

(with a few transverse beams for Manchester Central Train Shed roof being constructed simultaneously)

post-10633-0-57649800-1333925355_thumb.jpg

 

The upper arch plating being fitted -

 

post-10633-0-16614500-1333925395_thumb.jpg

 

post-10633-0-70280900-1333925432_thumb.jpg

 

post-10633-0-06314300-1333925473_thumb.jpg

 

- the opposing side braces are next

  • Like 4

Share this post


Link to post
Share on other sites

Hi, Peter

 

Thanks for your continuing interest, and hope you continue to like this build

 

Cheers

 

Ron

Share this post


Link to post
Share on other sites

It is very interesting. You are doing things that I had not thought about doing in plasticard. But it gives me ideas for when I do my layout.

Share this post


Link to post
Share on other sites

Cracking job so far. Watching with interest as I know the prototype well.

Share this post


Link to post
Share on other sites

Photo of the bridge showing the scope of the structure and bracings, etc. -

 

https://www.rmweb.co.uk/community/uploads/monthly_03_2012/post-10633-0-57219200-1333230014.jpg

What's quite surprising about this bridge is although the arches are quite substantial, the vertical pieces on which the bridge deck hangs appear to be quite flimsey.

Is there any structure under the deck to aid the support ?

Share this post


Link to post
Share on other sites

What's quite surprising about this bridge is although the arches are quite substantial, the vertical pieces on which the bridge deck hangs appear to be quite flimsey.

Is there any structure under the deck to aid the support ?

There is only a simple deck, IIRC .The arched structure needs to be pretty substantial, as it carries the load from all the vertical supports. Each vertical support, however, carries only a small part of the total weight of the deck.

  • Like 1

Share this post


Link to post
Share on other sites

Thanks Brian for answering Stubby for me

 

You are quite right - the bridge has 48 deck support hangers. Three (one from each of the three arches) for each of 16 deck support beams. There are also 4 deck beams, two at each end which are supported directly by the arch

 

If we assume that the train loadings are 500 tons on both tracks simultaneously i.e. 1000 tons, then each of the support beams must carry 50 tons plus a portion of the deck weight, and hence each hanger must carry 16.7+ tons. Each hanger is approx. 150mm x 25mm cross-section which would have a maximum aged load limit in excess of 150 tons. That is quite an important safety factor

 

Cheers

 

Ron

  • Like 2

Share this post


Link to post
Share on other sites

Last night's progress -

 

post-10633-0-46296500-1334065442_thumb.jpg

 

post-10633-0-36068700-1334065469_thumb.jpg

 

post-10633-0-63333800-1334065489_thumb.jpg

 

- now it's the diagonal cross bracings with integral bracings - a few pencil markings for the bracings attachment points

  • Like 3

Share this post


Link to post
Share on other sites

The first set of Cross-bracings fixed in place, at the crown of the arch -

 

The four bracings, two T section and two Flat section -

 

post-10633-0-45951400-1334079311_thumb.jpg

 

The two external braces have only two cross-braces, and the two internal braces have four cross-braces at the higher levels of the arch and five at the lower levels -

 

post-10633-0-63429400-1334079335_thumb.jpg

 

post-10633-0-86721000-1334079353_thumb.jpg

 

- now for the remaining 35 pairs

  • Like 5

Share this post


Link to post
Share on other sites

As others have suggested, this is surreal. Use of a common modelling material as an engineering medium. Progress is prodigious, too - but then as Ron's own link suggests this is in the 2010 Scratchbuilding Challenge, rather than 2012, he may be trying to make up for lost time!

Edited by Oldddudders

Share this post


Link to post
Share on other sites

As others have suggested, this is surreal. Use of a common modelling material as an engineering medium. Progress is prodigious, too - but then as Ron's own link suggests this is in the 2010 Scratchbuilding Challenge, rather than 2012, he may be trying to make up for lost time!

Thanks for the 'correction' to my signature

 

Definitely, always trying to make up for lost modelling time :sungum:

 

Cheers

 

Ron

Share this post


Link to post
Share on other sites

Couple of pictures -

 

post-10633-0-90083700-1334414671_thumb.jpg

Note: The cross-braces are constructed using the jig - two rectangular cut-outs - to ensure they are all identical and fit exactly between the the main braces

 

post-10633-0-27954000-1334414704_thumb.jpg

 

View with another six external braces fitted -

post-10633-0-58673400-1334415129_thumb.jpg

 

- matching internal braces next

  • Like 9

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.