N15class Posted April 14, 2012 Share Posted April 14, 2012 It is coming on well. It must be becoming quite rigid now. Are you doing the arches one at a time or have you all three on the go? Link to post Share on other sites More sharing options...
Ron Heggs Posted April 14, 2012 Author Share Posted April 14, 2012 It is coming on well. It must be becoming quite rigid now. Are you doing the arches one at a time or have you all three on the go? Hi, Peter Yes, the bracings are starting to reduce the arch flexibility and make it far more rigid. I can already see that the vertical rigidity will make the deck support/loading a reality The arches are being built one at a time. This first one will be the middle of the three. The two outer arches are identical, and some of the cross-bracings are opposite-hand to those on the middle arch Will have to increase the strip cutting time, to speed-up the build of this first arch, and attach it to the deck Cheers Ron Link to post Share on other sites More sharing options...
Ron Heggs Posted April 14, 2012 Author Share Posted April 14, 2012 All the main external braces fitted along with the relevant cross-braces - Positioned, but not fixed, on the deck - - internal braces and cross-braces next - Link to post Share on other sites More sharing options...
Ron Heggs Posted April 15, 2012 Author Share Posted April 15, 2012 I must thank all those members who are following this topic/thread for your continuing interest, and a special thanks for clicking on 'LIKE THIS' Cheers Ron Link to post Share on other sites More sharing options...
SXHALL Posted April 15, 2012 Share Posted April 15, 2012 Hi Ron, Will you be fixing track to this before it is completed? Can't wait to see it finished with some stock staged on it. Also will this be going on to Manchester Central or is just a detour to keep you from getting bored other tasks!? It is a superb build but everything you have posted on here is superb so would not have expected anything less really. Steven Link to post Share on other sites More sharing options...
Ron Heggs Posted April 15, 2012 Author Share Posted April 15, 2012 Hi Ron, Will you be fixing track to this before it is completed? Can't wait to see it finished with some stock staged on it. Also will this be going on to Manchester Central or is just a detour to keep you from getting bored other tasks!? It is a superb build but everything you have posted on here is superb so would not have expected anything less really. Steven Hi, Steven Eventually track will be laid, not sure whether before the challenge ends in October The bridge will be used on part of the layout which will pass through the summerhouse, visually disconnected from the main part of the layout, which will be indoors I do switch modelling tasks frequently, as you rightly say to reduce the boredom with tedious and lengthy builds Thank you for your much appreciated comments Cheers Ron Link to post Share on other sites More sharing options...
Ron Heggs Posted April 15, 2012 Author Share Posted April 15, 2012 Another six internal braces/cross-bracings fitted this evening - A brace unit ready to fit - The brace unit threaded through the external brace member - The brace unit fixed in its location - Link to post Share on other sites More sharing options...
Ron Heggs Posted April 15, 2012 Author Share Posted April 15, 2012 Some of you may have noticed that the last picture in post #53 showed a packet or two of Archer 3D transfers for rivet heads Yes, I am going to try these out on the bridge before painting Link to post Share on other sites More sharing options...
ColinW Posted April 17, 2012 Share Posted April 17, 2012 Hi Ron, You are making good progress with the arch, no surprise there. looking forward to seeing more pictures as you continue. Colin Link to post Share on other sites More sharing options...
N15class Posted April 17, 2012 Share Posted April 17, 2012 Some of you may have noticed that the last picture in post #53 showed a packet or two of Archer 3D transfers for rivet heads Yes, I am going to try these out on the bridge before painting That may well take longer than the construction. Looking very impressive with the arch over the bed. Link to post Share on other sites More sharing options...
hymek2 Posted April 17, 2012 Share Posted April 17, 2012 Somehow the "Like this" button seems totally inadequate.... amazing work. Link to post Share on other sites More sharing options...
Ron Heggs Posted April 17, 2012 Author Share Posted April 17, 2012 Hi Ron, You are making good progress with the arch, no surprise there. looking forward to seeing more pictures as you continue. Colin Thanks Colin - there will be plenty more pictures to post as the build continues Ron Link to post Share on other sites More sharing options...
Ron Heggs Posted April 17, 2012 Author Share Posted April 17, 2012 That may well take longer than the construction. Looking very impressive with the arch over the bed. Hi, Peter Thanks You may well be right about the rivet head placements taking a little longer than the build Ron Link to post Share on other sites More sharing options...
Ron Heggs Posted April 17, 2012 Author Share Posted April 17, 2012 Somehow the "Like this" button seems totally inadequate.... amazing work. Thank you - your comments are much appreciated Ron Link to post Share on other sites More sharing options...
Ron Heggs Posted April 17, 2012 Author Share Posted April 17, 2012 The last of the internal braces with five cross-bracings - The middle arch build so far - - mounted temporarily on/through the deck - now to complete the remaining internal bracings for the remaining 40% of this arch Link to post Share on other sites More sharing options...
RMweb Gold John B Posted April 18, 2012 RMweb Gold Share Posted April 18, 2012 Stunning stuff. This is true model engineering - not the lathe-turned and paraffin-driven stuff you see at a typical model engineering exhibition, of course - but engineering of the highest order nonetheless. Link to post Share on other sites More sharing options...
Ron Heggs Posted April 19, 2012 Author Share Posted April 19, 2012 Couldn't post these photos last night as the site was off-line The arch is complete and fitted to the deck - The next step is to fit the suspension hanger/struts Link to post Share on other sites More sharing options...
Ron Heggs Posted April 19, 2012 Author Share Posted April 19, 2012 Stunning stuff. This is true model engineering - not the lathe-turned and paraffin-driven stuff you see at a typical model engineering exhibition, of course - but engineering of the highest order nonetheless. Hi, John Thanks for your comments - My model builds need to function in a similar way as the real structures - bridges need to be a real scale construction, not a facade - although these bridges couldn't really be constructed in any other way to represent the actual structure Cheers Ron Link to post Share on other sites More sharing options...
N15class Posted April 19, 2012 Share Posted April 19, 2012 So when is the first loco crossing? Looks as if it will have no problems with the weight. Link to post Share on other sites More sharing options...
Ron Heggs Posted April 19, 2012 Author Share Posted April 19, 2012 So when is the first loco crossing? Looks as if it will have no problems with the weight. Hi, Peter May try a test load once the suspension hangers/struts are in place on this first arch - if only to check the fixings performance Ron Link to post Share on other sites More sharing options...
Ron Heggs Posted April 24, 2012 Author Share Posted April 24, 2012 The first two suspension/hangers fitted - - another 14 to fit Link to post Share on other sites More sharing options...
RMweb Gold Stubby47 Posted April 25, 2012 RMweb Gold Share Posted April 25, 2012 How does the tensile strength of the model plasticard compare to that of the full size steel ? I'm guessing the plasticard is proportionally stronger ? Link to post Share on other sites More sharing options...
Ron Heggs Posted April 25, 2012 Author Share Posted April 25, 2012 How does the tensile strength of the model plasticard compare to that of the full size steel ? I'm guessing the plasticard is proportionally stronger ? Hi, Stubby The answer to your question is in two parts - 1. Material Strengths Styrene: Ultimate Tensile Strength is 40 Mpa (40N/mm2) Structural Steel: Ultimate Tensile Strength is 400 Mpa (400N/mm2) The actual bridge deck suspension hangers are 25mm x 150mm cross-section steel The model suspension hangers are 0.5mm x 2mm cross-section styrene Max Force (Load) = Ultimate Tensile Strength x Cross-sectional Area Styrene: Force = 40MPa x 0.5 x 2 x 100 = 4kN Steel: Force = 400MPa x 25x 150 x 100 = 150,000kN Since the model scale is 1:76.2, the area ratio is 1:5806.44 This means that the scale equivalent scale Force would be 4kN x 5806.44 = 23,225kN, some 15% of that of the actual 2. Scale Equivalent Loads Assuming a model loco is approx. 500g, then the scale equivalent mass would be 442,451g = 443kg = 0.443tonnes Whereas, the prototype would be nearer 100tonnes. This makes the model loco only say 0.5% of the actual In conclusion, the model suspension hangers have a greater equivalent model load capability some 30 times (15% / 0.5%) greater than the actual prototype, as the model locos, etc. are much lighter in scale terms Hope I haven’t confused you too much Cheers Ron Link to post Share on other sites More sharing options...
RMweb Gold Stubby47 Posted April 25, 2012 RMweb Gold Share Posted April 25, 2012 Ah, so what you're saying is : although the model is proportionally not as strong as the prototype, because the model locos are considerably lighter than their full size eqivalents, the model bridge is still well within tolerances for supporting said model loco. Phew ! It's just that those hangers look very thin (mind you, I also said that about the real ones - what do I know ?) Thanks Stu Edit : The other main difference, of course is that the real hangers are bolted to the other bits of the bridge at each end, where as the model is only glued together - which could result in weaker joints (except the glue is probably stronger than the plastic !) Link to post Share on other sites More sharing options...
scanman Posted April 26, 2012 Share Posted April 26, 2012 Hi Ron - Been 'offline' for a while. Stunning progress! Two things - you say this model will go in a summerhouse? No danger of warping in the heat? Secondly - very early on it looked like you will building the intial structure over a plan. If so - how did you prevent the styrene sticking to the plan? I only ask because I've got to model the girder-work associated with the canopyof a platform at Brisol Temple Meads... Regs Ian Link to post Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.