RMweb Premium uax6 Posted April 13, 2013 RMweb Premium Share Posted April 13, 2013 Are you going to raise the height of the arch, or leave it so that the arch is flatter? These are important things to consider, personally I would make the arch flatter, as that is what would be more likely to happen, why would the railway pay for more materials to gain clearence where it isn't required? Looking forward to photos of all the templates! Andy G Link to post Share on other sites More sharing options...
67A Posted April 13, 2013 Share Posted April 13, 2013 Hi Jeff, I was catching up and looked at your drawing and dimensions and hoped I was not to be too late in advising on the 6ft clearance, but being late as usual I see you have attended to it....... good man!!!! I'll be keeping an eye on the bridge building. To answer your question 'where is everyone' ...... well I have been getting half plastered but not in the fun sense, the den is now half done. Link to post Share on other sites More sharing options...
RMweb Premium Physicsman Posted April 13, 2013 Author RMweb Premium Share Posted April 13, 2013 Next result.... Tunnel portal width up from 104mm to 120mm, portal height increased by 4mm to 74mm.... (arch same size, verical sides 40 to 44mm.... see diagram): Coach on outer rail (30" radius) ... clear both into and out of tunnel... Coach on inner rail (27") ... clear both into and out of tunnel... BUT only 1mm clearance when half-way through (at max. overhang)... SOLUTION: The portal width has been increased by another 8mm. To maintain the overall tunnel aspect ratio, all dimensions are now 20%ish greater than on my original diagram in post #5841. I'll redraw the dimensions and do a card mock-up in the morning to show the effect. It looks in proportion and it allows free passage of rolling stock in the most awkward (curvature-wise) area of the layout. Right - BOREDOM TIME OVER - YOU CAN WAKE UP NOW!! Jeff 2 Link to post Share on other sites More sharing options...
RMweb Premium Jason T Posted April 13, 2013 RMweb Premium Share Posted April 13, 2013 Funnily enough, I make mockups out of mounting board and cut them as accurately as possible. It costs peanuts and if it is right, then I use it to build the model itself. Been lucky so far I'm not trying to steer people away here, but I have been busy with the airbrush today and despite my fear of it, have been quite pleased with the outcome. Which leads me into the next question: have you bought an airbrush yet Jeff? Link to post Share on other sites More sharing options...
RMweb Premium Physicsman Posted April 13, 2013 Author RMweb Premium Share Posted April 13, 2013 Are you going to raise the height of the arch, or leave it so that the arch is flatter? These are important things to consider, personally I would make the arch flatter, as that is what would be more likely to happen, why would the railway pay for more materials to gain clearence where it isn't required? Looking forward to photos of all the templates! Andy G Good suggestion Andy. I could raise the vertical portal sides by another 4mm and flatten the arch, keeping the portal width as in the photos. I'll draw it up and see if it looks ok. Jeff Link to post Share on other sites More sharing options...
RMweb Premium Physicsman Posted April 13, 2013 Author RMweb Premium Share Posted April 13, 2013 Funnily enough, I make mockups out of mounting board and cut them as accurately as possible. It costs peanuts and if it is right, then I use it to build the model itself. Been lucky so far I'm not trying to steer people away here, but I have been busy with the airbrush today and despite my fear of it, have been quite pleased with the outcome. Which leads me into the next question: have you bought an airbrush yet Jeff? Evening Jason, I was wondering where you'd got to! Am I wrong in interpreting Larry's comment on Bacup as a criticism of your weathering on the upper half of your models? Haven't got an airbrush yet. Bankrupting myself with plaster etc costs. It WILL happen over the next few months, I guarantee it! Jeff Link to post Share on other sites More sharing options...
RMweb Premium southern42 Posted April 13, 2013 RMweb Premium Share Posted April 13, 2013 I go out for the day and come back to pages to catch up on. A good read, though. The bridge looks really interesting with all the different shapes and colours. You should enjoy building that one. Looks like you've already started - posted while I am still at the keyboard. That's what I like to see. So I have some more catching up to do..... I'd better sign off before you lot get too far ahead of me again. Pollygone Link to post Share on other sites More sharing options...
RMweb Premium Physicsman Posted April 13, 2013 Author RMweb Premium Share Posted April 13, 2013 Hi Jeff, I was catching up and looked at your drawing and dimensions and hoped I was not to be too late in advising on the 6ft clearance, but being late as usual I see you have attended to it....... good man!!!! I'll be keeping an eye on the bridge building. To answer your question 'where is everyone' ...... well I have been getting half plastered but not in the fun sense, the den is now half done. Hi Mike. I really ought to have remembered the 6' before I did. As soon as I cut the first arch in card I thought "that's a bit narrow" - then it clicked! If I can get the dimensions to work - and I'm close - I'll start cutting ply tomorrow. Plastered? What's plaster - NEVER heard of the stuff! Well done Mike - you'll have a den to be proud of.... Funny thing today. It's warmed up a bit. Garden temperature 15C, uninsulated garage temp 15C, insulated bunker 9C!!!! So the insulation DOES work - just need to leave the door open to restore equilibrium! Jeff Link to post Share on other sites More sharing options...
RMweb Premium uax6 Posted April 13, 2013 RMweb Premium Share Posted April 13, 2013 (edited) Jeff, I'm confused (again!) I thought this was for a bridge not tunnel? If it is, I would say that you have enough height for overhead electrics wires! Bring the crown of the arch down as you suggest and it will look better. Otherwise looking good Andy G (edited to make sense!) Edited April 13, 2013 by uax6 Link to post Share on other sites More sharing options...
RMweb Premium Jason T Posted April 13, 2013 RMweb Premium Share Posted April 13, 2013 I think Larry's comments relate more to the bizarre weathering that Hornby and Bachmann seem to add to their models, more H than B really. My previous efforts have been a bit hit and miss really, hence pestering Tim for tips, but I think I now have a better idea. The Cravens unit I had a go at today is sort of based on colour photos of the real thing sat at the buffer stops at Bacup but needs a fair bit of tweaking with dry brushing, powders, etc. Tim recommends the use of T-Cut before starting, to get a metallic effect as a base, which I would never have thought of. One look at Gilbert's Peterborough North and the fantastic work Tim has done on the fleet for that is proof enough that it is the way to go though. Link to post Share on other sites More sharing options...
RMweb Premium Physicsman Posted April 13, 2013 Author RMweb Premium Share Posted April 13, 2013 Jeff, I'm confused (again!) I thought this was for a bridge not tunnel? If it is, I would say that you have enough height for overhead electrics wires! Bring the crown of the arch down as you suggest and it will look better. Otherwise looking good Andy G (edited to make sense!) Andy - have a look at this link. I'm not making this up - this is a bridge on the S&C.... http://farm7.staticflickr.com/6086/6062134035_e6828c0bed_z.jpg I'm going to push the sides up and flatten the arch. Check posts tomorrow... Jeff Link to post Share on other sites More sharing options...
RMweb Premium Physicsman Posted April 13, 2013 Author RMweb Premium Share Posted April 13, 2013 I think Larry's comments relate more to the bizarre weathering that Hornby and Bachmann seem to add to their models, more H than B really. My previous efforts have been a bit hit and miss really, hence pestering Tim for tips, but I think I now have a better idea. The Cravens unit I had a go at today is sort of based on colour photos of the real thing sat at the buffer stops at Bacup but needs a fair bit of tweaking with dry brushing, powders, etc. Tim recommends the use of T-Cut before starting, to get a metallic effect as a base, which I would never have thought of. One look at Gilbert's Peterborough North and the fantastic work Tim has done on the fleet for that is proof enough that it is the way to go though. Must admit I tend not to look at Gilbert's layout - it's too spectacular for words and makes me feel totally inadequate! I think your weathering looks good. As I pointed out on your thread, the "heavily weathered" Hornby 8F is a lovely model but dirty.... where? Lol. Jeff Link to post Share on other sites More sharing options...
RMweb Premium Physicsman Posted April 13, 2013 Author RMweb Premium Share Posted April 13, 2013 Andy, Arch flattened, portal width as before (120mm/176mm), all seems ok... Jeff ps. Wood cutting starts tomorrow afternoon! 1 Link to post Share on other sites More sharing options...
Peter Kazmierczak Posted April 13, 2013 Share Posted April 13, 2013 Jeff, Just a thought but you might want to borrow someone's Mk3 coach to see if that'll pass comfortably through the structure. You might never have any intention (at the moment) of running more modern stock, but who knows in the future? Also friends might want to run some of their trains on your layout. Regards, Peter Link to post Share on other sites More sharing options...
RMweb Gold Donw Posted April 13, 2013 RMweb Gold Share Posted April 13, 2013 That last one looks ok to me. It is easy to forget that you need to take into account wider spacing. Being a GWR man we have the excuse of old BG spacings and of course a lot of tunnels and bridges were built to accomodate BG tracks. BTW your original figure of 24 is incorrect if you are using 00. The track gauge is narrower but the stock isn't I would suggest a minimum spacing of 26.5 for 00 track even on straight track you don't want your passengers getting their heads knocked off. Don Link to post Share on other sites More sharing options...
Scott B Posted April 13, 2013 Share Posted April 13, 2013 I would agree with that Peter, and I am sure that Jeff would certainly be better off using a Class 40 or 45, as I am sure he said he will be running these than, rather than a Mk1. They would certainly be a lot closer to a Mk3 as well. Scott Jeff, Just a thought but you might want to borrow someone's Mk3 coach to see if that'll pass comfortably through the structure. You might never have any intention (at the moment) of running more modern stock, but who knows in the future? Also friends might want to run some of their trains on your layout. Regards, Peter Link to post Share on other sites More sharing options...
emt_911 Posted April 13, 2013 Share Posted April 13, 2013 Jeff I like the improved portal which looks right. However, I have to agree with Peter about testing with a Mk III coach just to make sure. Duncan Link to post Share on other sites More sharing options...
RMweb Premium Physicsman Posted April 13, 2013 Author RMweb Premium Share Posted April 13, 2013 Peter, Duncan, Scott. Thanks for the suggestions re. Mk 3 coaches. I don't have any of those, but I've certainly got class 40s and 45s. There's actually a 45 in the bunker right now - I've been using it as a test vehicle. I'll test the card portal with a 45 tomorrow. Don, Aside from the fiddle yard, which I set the "6'" at around the 25mm mark, either side of the main line, I've used a spacing of between 30mm and 32mm - apart from the tight corner where the curves had to diverge slightly. I certainly didn't want any decapitations!! Jeff Link to post Share on other sites More sharing options...
Peter Kazmierczak Posted April 13, 2013 Share Posted April 13, 2013 Jeff, If you have access to a Jouef Cl.40, so much the better. Link to post Share on other sites More sharing options...
RMweb Premium Physicsman Posted April 13, 2013 Author RMweb Premium Share Posted April 13, 2013 Jeff, If you have access to a Jouef Cl.40, so much the better. I'm afraid I only have one class 40 - a blue BR liveried Bachmann. I'll add that to the test vehicles tomorrow. Jeff Link to post Share on other sites More sharing options...
jukebox Posted April 13, 2013 Share Posted April 13, 2013 Next result.... Tunnel portal width up from 104mm to 120mm, portal height increased by 4mm to 74mm.... (arch same size, verical sides 40 to 44mm.... see diagram): Coach on outer rail (30" radius) ... clear both into and out of tunnel... *snip* BUT only 1mm clearance when half-way through (at max. overhang)... 100_2941.JPG SOLUTION: The portal width has been increased by another 8mm. To maintain the overall tunnel aspect ratio, all dimensions are now 20%ish greater than on my original diagram in post #5841. I'll redraw the dimensions and do a card mock-up in the morning to show the effect. It looks in proportion and it allows free passage of rolling stock in the most awkward (curvature-wise) area of the layout. Right - BOREDOM TIME OVER - YOU CAN WAKE UP NOW!! Jeff Jeff, Looking from that view, I'm curious why you didn't just raise the tunnel vertically (by ~8mm?) and keep the existing shape? More than one way to skin a cat etc.etc. Cheers Scott Link to post Share on other sites More sharing options...
RMweb Premium Physicsman Posted April 14, 2013 Author RMweb Premium Share Posted April 14, 2013 Jeff, Looking from that view, I'm curious why you didn't just raise the tunnel vertically (by ~8mm?) and keep the existing shape? More than one way to skin a cat etc.etc. Cheers Scott Yes Scott, many ways to skin the cat! My experiments have only cost me a bit of time and a few bits of cereal packet card. I could change plenty of things and - if I didn't tell anybody nobody would be any the wiser. Who is to say that the particular bridge I'm using as the prototype is in any way typical? So I'll go along with my final card cut - provided it's ok with the big diesel locos. If not, a bit more tweaking will be done. It's amazing how much fun this is. And, more importantly, it gives confidence that the wood-cut version will be ok! Jeff Link to post Share on other sites More sharing options...
RMweb Premium Physicsman Posted April 14, 2013 Author RMweb Premium Share Posted April 14, 2013 (edited) "Final" tests conducted... Using the card template in the last set of photos (post # 5865) there was no problem at all with clearance for classes 40 and 45. At least a 5mm gap, even at maximum overhang (probably a little bit more). I shall now draw the outlines onto the 12mm and 3mm ply I'm going to use for the body of the bridge - photos (inevitably) eventually! Jeff Edited April 14, 2013 by Physicsman 1 Link to post Share on other sites More sharing options...
RMweb Gold Donw Posted April 14, 2013 RMweb Gold Share Posted April 14, 2013 Well worth doing the card one first you really wouldn't want to keep changeing the wooden one. I think you have it just right now. Nice colouring on the photo do you intend to copy that. Don Link to post Share on other sites More sharing options...
Andrew P Posted April 14, 2013 Share Posted April 14, 2013 Hi Jeff, I have just played catch up as I have been so busy of late and only had little glances on here now and again, (will I get the cane or LINES for that) hahahahha. Have you considered the length of a Bayer Garrett? for going through that hole young sir? And did I read somewhere about some grass going down, or was that a smokescrene to keep me looking, (or was it the grass going up in pipe smoke,) hohohohoheheheheeeee Back Later. Bodgit, Little Weed Link to post Share on other sites More sharing options...
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