Ron Heggs

Hi, Just finished the first 10 trusses. They take approx. 30 minutes each, so that means about another 70 hours work But this may be reduced due to some simplification of the assembly routine Ron

Hi, Ben Thanks for your comments Original components are produced and checked for dimensional accuracy with a digital caliper Individual component lengths are checked by placing side by side with the ends against a steel rule. Any noticably shorter or longer items are checked against an original component. Any which do not fall witihin an acceptable tolerance are consigned to plastic containers for future re-use Similarly, angled components are stacked on top of one another. Any which show a greater or lesser angle are checked against an original component, and unacceptable items are placed in plastic containers for re-use Acceptable precision and accuracy, are a judgement made by the modeller, and dependant on the model and the need to construct as an accurate structure as required to fulfill the modellers requirement, be it for effect and to portray a prototype In the end it is all personal judgement Ron

Hi, Ian Thanks for your comments. Will have to put that suggestion on the back burner for the moment. But may consider bespoke structures in the short term, if anyone wants a particular bridge, etc constructed in plastic Ron

Hi, Shamouti Thanks for your suggestion. I have two of those picnic cooler packs lying around, so will try them out Thanks again Ron

Hi, Will be able tell after the first 10 are built Ron

Just completed the first of 148 cross-braced brace trusses (The truss is an attempt at a true scale copy of the existing steel structure, so the plastic strip thickness is extremely thin at 10th , a scale ¾†5th would be nearer true scale, but would be far to flimsy and susceptible to solvent meltdown (dissolving) Other than this diversion from scale, the remaining dimensions are scale) It was intended as a trial build, but it has turned out successful They are each 116mm long and produced from 10th plastic strip The 28 individual cross-brace strips are 10th x 0.75mm x 8.5mm fixed at 7.25 centres 14 of each fixed to each side of 10th x 1mm x 116 strips spaced 5mm apart Additional strips 10th x 2mm x 116mm are fixed to the outer edges to form T section beams The final overall dimensions of the brace truss is 7.5mm wide x 2mm deep x 116mm long Is it robust and undistorted? Yes It is obviously very light and could easily be inadvertently damaged by mishandling So here goes for another 147 The total is made up of – 32 with 3.75mm wide T beams 76 with 3mm wide T beams 40 with 2mm wide T beams

Modelling the 1877 viaduct bridge #2 This viaduct bridge is the Cornbrook Viaduct Bridge #2, which is some 50 metres west of Cornbrook Viaduct Bridge #1 This Google link shows the relevant juxtaposition of the viaduct bridges - http://maps.google.co.uk/maps?hl=en&ie=UTF8&t=k&ll=53.474702,-2.256977&spn=0.002439,0.010278&z=18 Bridge #1 is to the right, whilst Bridge #2 is to the left. The long viaduct bridge to the North of these other two viaduct bridges is the Castlefield Viaduct 1894 The following drawings have been produced on CAD, with details taken from OS map, archive and present day photographs The overall length is 1444mm, with a height to the top of the decorative pillars of 333mm The length of the western span is 848mm, and the eastern span is 596mm The width of the side cross-bracings varies between the end and centre sections of each bridge span The bracing members are constructed as trusses in only one diagonal direction in each span Details will be given as the construction proceeds Cross-section and true-length side truss detail Face and Side Elevations Note: The pillars are elliptical in cross-section To be continued - with construction as it proceeds

Modelling the 1877 viaduct bridge #1 - Continuation Within each pair of the central braces a unique set of 4 pairs of shaped strip braces are positioned. Shown RED in the picture below Deck Beams The deck is produced from 40th plasticard supported on deck beams in the form of RSJs. These are produced from 40th x 7.5mm and 40th x 4mm strips The beams are fitted at the same centres as the vertical trusses. Four transverse beams made from 20th x 5mm and 2.5mm strips are placed between each pair of deck beams. Additionally, angle strips are provided as deck plate fixings Overhead Span Braces Two overhead brace assemblies are positioned as shown on the bridge plan, and photo Each assembly is produced from 20th strips and 40th plasticard The bracings are positioned on both external faces of the two truss members, with the opposing braces sandwiched between the two truss members The complete bridge structure is below The structure now awaits some additional items, such as a handrail/barrier fixed to the eastern end of the north span, used to protect the open space between this viaduct bridge and the adjacent 1894 viaduct bridge Painting and weathering will proceed at some time in the future when all the viaduct bridges will be treated simultaneously The bridge deck will be covered with cork prior to track laying and ballasting

Yes, but there was just no room in our 4 bed detached for a 10m x 5m layout plus access around it, and the milder climate here did beckon. We were lucky that the second villa we viewed had an underbuild which could house my intended layout, after the internal walls were removed. Building licence has been applied for and work should start early this coming summer I think the prospect of moving the largest model structure once insitu i.e. the train shed, some 2200mm x 850mm would frighten even me Maybe a professional video at some time in the future would be a more practical approach to enabling public viewing Ron

I can just about visualise where you are now. It just shows you how little TV I actually get to see. I believe the arched footbridge you mention is a later addition to the area, after the railways disappeared and before the Metrolink was introduced The intention is to model as far west as the viaduct bridges extend Model layout extent Regards Ron

To all those wondering why the cans of beer and not any other item The beer is only 29 cents (26p) a can, so any damage is minimal if they fell off

Hi, Mike If I had a Laser Cutter, then yes I would use the CAD program. But no such luck, not at £2500+. So all the plastic is measured and cut by hand You may have noticed in the last picture the bridge span is actually supported off two bottles of EMA Plastic Weld. Impossible to obtain in Spain, and difficult to get delivered by post to Spain. But there are amenable model suppliers I do use Butanone for my track building, but again cannot be sourced in Spain, nor can it be shipped to Spain. But as it is essentially MEK, the local plumbing outlet sells this as a primer for uPVC and PVC piping before the application of adhesive, and it is cheap The biggest problem using these solvents is the evaporation rate [it is slightly warmer over here than it is in the UK], when the bottle is open for even the shortest time. I am looking for a very narrow necked bottle, which should reduce this problem

AutoCAD 2000 given to me when I retired I use 2D wireframe, 3D wireframe, surface and solid modelling, whichever suits the job in hand If you are talking about 'Coronation Street', the answer is no. Their viaduct is just a brick facade The nearest viaduct to Granada Studios is just north of Liverpool Street by the site of the Manchester & Liverpool Railway. The Castlefield and Cornbrook viaducts are south of Liverpool Street, and the LNWR viaducts to the West across the River Irwell Thanks for your interest Ron

Continuing construction of the Bridge Spans- The vertical trusses have been completed and the South Span has been built Assembly of span with just the vertical trusses and the end joists in place Completed span. The central five trusses and the two end trusses are without vertical reinforcement plates Closeup of span showing the gusset plates and diagonal bracings. Cross bracing is only to the three central trusses In case you think these plastic structure are flimsy, study this next picture No discernible deflection i.e. less than 1mm, and YES the cans are full and unopened, and NO I didn’t empty them immediately after taking the picture. That is a loading of 1 litre / 1kg So the complete bridge with the two spans support the bridge deck should be able to support a minimum of 2 kg without any significant deflection The next post will be the completed bridge structure with the bridge deck in place, in about two weeks time

CASTLEFIELD VIADUCTS - MANCHESTER There are four viaducts at Castlefield, Manchester, built almost entirely in brick. Where they pass over railway lines and canal wharves, steel and wrought iron bridging structures employing various structural design arrangements have been used Castlefield Viaducts -1847-1849 Manchester South Junction & Altrincham Railway, the one on the Altrincham line is the most southerly of all the viaducts and the other on the line to Salford/Eccles passes under the two Midland viaducts. East of Castlefield Junction the lines extend to Oxford Road and London Road (Piccadilly). (Presently used by Metrolink) Cornbrook Viaduct -1877 Midland Railway, built adjacent to and the North of the 1849 Castlefield Viaduct, was used mainly for trains to the South and East. (Presently used by Metrolink) Castlefield Viaduct -1894 Midland Railway, built adjacent to and the North of the 1877 Cornbrook Viaduct, carried the lines to the West, Liverpool, Cornbrook Carriage sidings and Trafford Park locomotive shed. (Presently disused) The lines into Manchester Central Station, CLC Goods Warehouse and GNR Deansgate Goods Warehouse used the two viaducts built by the Midland Railway The 1877 viaduct has two separate bridge spans, whereas the 1894 viaduct is a single bridge comprising eight individual spans - The 1894 viaduct bridge structure is already work in progress, see Gallery link Google Maps link : http://maps.google.co.uk/maps?f=q&source=s_q&hl=en&geocode=&q=Castlefield&sll=53.800651,-4.064941&sspn=22.297654,67.456055&ie=UTF8&hq=&hnear=Castlefield,+Greater+Manchester,+United+Kingdom&ll=53.4746,-2.256306&spn=0.00273,0.010278&t=k&z=18 Modelling the 1877 viaduct bridge #1 This bridge spans the MSJ&R lines to Salford, and is built on the skew. The northern span runs east-west and has a length of 150ft (600mm). The southern span runs at an angle of 3.1° from east to west, and is 166ft (664mm) long. The resulting bridge deck is 84ft (332mm) wide at the east end, and 66ft (264mm) wide at the west end. The skew angle is -63° from North. The lines run on a curve between the bridge spans Plan of bridge without the two span braces Plan of bridge with under deck steel dimensions (4mm scale) North and South Spans - south elevations 3D view of South Span 3D views of Vertical Truss Structure with strengthening plates Vertical Truss Structure without strengthening plates - Modelled in plastic Plastic Modelling in 4mm scale General comment Butanone/MEK (Methyl Ether Ketone) is used for temporary assembly where necessary EMA Plastic Weld is used for all permanent/final assembly Templates and jigs were not used Vertical Truss Structures The structure is built using four pieces of Evergreen 291 - 60th angle section, each 59mm long, with a 10th x 40th x 7mm long strip sandwiched between them at each end. Eight diagonal strips of the same section 7.5mm long are fitted at 5mm intervals between two of the angle sections. This is repeated for the other side, so that the diagonal strips appear as X’s, when viewed from either side Using a 0.55mm drill bit, holes are made through each pair of diagonal strips forming an X, spinning the drill bit with finger and thumb. Pieces of 0.5mm plastic rod 2mm long are fitted through each pair of adjacent holes, to represent the fixing bolts Additional fixing plates/shims, 20th x 100th x 7.5mm long, are added at the end of each pair of angle sections When constructing structures with strengthening plates, two strips 20th x 4mm x 59mm are fixed instead of the four fixing plates/shims The north span requires 13 in total, six without strengthening plates, and seven with strengthening plates. The south span requires 15 in total, seven without strengthening plates, and eight with strengthening plates South span – Lower beam Lower Span Beams The lower beams are constructed from two vertical strips 20th x 7mm, fitted top and bottom with strips 20th x 60th. Strips 10th x 30th are fixed vertically within the angle formed by the top and bottom strips Spacer plates are made from 20th plastic card 7.5mm wide x 7mm high with strips 20th x 60th x 7.5mm fitted to the bottom edge The two channel beams are fitted with the spacer plates at 40mm intervals. On the north span the first spacer is 30mm from the west end, and the last spacer is 50mm from the east end. The dimensions for the south span are 32mm from either end. The plates are fixed flush with the bottom of the channels The ends of the each beam assembly are fitted with pieces of plastic card 20th x 8mm x 11.5mm Upper Span Beams The upper beams are constructed from two vertical strips 20th x 7mm, fitted at the bottom only with strips 20th x 60th. Strips 10th x 30th are fixed vertically within the angle formed by the bottom strips Spacer plates are made from 20th plastic card 7.5mm wide x 7mm high with strips 20th x 60th x 7.5mm fitted to the bottom edge On the north span the first spacer is 20mm from the west end, and the last spacer is 40mm from the east end. These dimensions are 20mm from west and east ends, on the south span A strip of plastic card 20th x 11.5mm wide is fixed across the top of the two channels with 1.5mm overhang along each side. Strips 10th x 30th are fixed vertically to each side of the assembly, within the angle formed by the top strip End pieces are not required Sloping End Beams Following the differences shown on the drawing elevations, these are built in a similar fashion as the top beams Next step is the assembly of both North and South Spans Work in progress ..... to be continued

Sorry Jim, had so many comments I missed your question, have just answered similar question from Michael Delamar If you have any further questions please ask All the best