After making 2 laser cut models I couldn't help myself - I made another one.
No. Of course I planned that before as this will be the bridge used by the H0e line while climbing up the hill.
I saw in the internet some laser cut bridges from the German company Noch - and I thought the bent truss bridge with the smaller radius (H0 scale) could do also for H0e.
And there we are. As it were only 32 parts I didn't do any building pictures. It was nicely cut, everything fits well and if you are happy with the green finish no painting is required. The glue coming with the kit is a fast setting PVA, too fast for me in some cases - so I used the much thinner and slow setting stuff I used also for the station - and which is by the way from Poundland :)
(https://farm8.staticflickr.com/7576/26213303463_42e2355582_b.jpg) (https://flic.kr/p/FWo2RZ)IMGP5429 (https://flic.kr/p/FWo2RZ) by Gerhard Novak (https://www.flickr.com/photos/137050108@N03/), on Flickr
(https://farm8.staticflickr.com/7313/26724007352_8de7617324_b.jpg) (https://flic.kr/p/GHvwks)IMGP5428 (https://flic.kr/p/GHvwks) by Gerhard Novak (https://www.flickr.com/photos/137050108@N03/), on Flickr
I am quite happy with this result, it looks realistic and is stable enough for what it should hold.
(https://farm8.staticflickr.com/7311/26724009202_9b3930c6b8_b.jpg) (https://flic.kr/p/GHvwTm)IMGP5426 (https://flic.kr/p/GHvwTm) by Gerhard Novak (https://www.flickr.com/photos/137050108@N03/), on Flickr
Looks nice Gerhard, thank you for sharing. Are you tempted to slew the track to one side, and have a path or roadway running parralel? Have seen same in a couple of places around the world, and gives a good reason for the generous width of the model.
Andrew,
I think I will stay in the centre of the bridge. It doesn't matter that it is 9mm track - the rolling stock of a narrow gauge is wider than the track.
Probably I use a smaller radius than the bridge has - means the track will be more on the inside at both ends and further out in the middle.
Gerhard,
Do you or any of your friends model the DR at all? I ve had some custom DR transfers made, far more than I can ever use myself. If you would like any, please email me offline at andreiemery@yahoo.com
Hopefully I've managed to attach some photos to this email...
Andrew,
thanks for the kind offer, I am modelling Austria in the 90th - so I have no use for the transfers, but other people in this forum may!
best regards
Gerhard
Just a general note on bridges in curves.
I have not seen a bridge with curved span in 1:1, and I can't fathom how that is supposed to work structurally: essentially, the outward curved bit overhangs the support points at the piers, i.e. if the span is long enough the bridge will tilt off its supports; if not, the loading on the piers is very uneven.
While popular with model railway manufacturers, curved spans should not be used on model railways, unless you're not bothered about the 'model' in model railway.
On the prototype the bridge spans are straight, i.e. a polygon in the case of a string of spans, with the track curved across.
Which is where we have an edge with narrow gauge: as the model bridges are for standard gauge the track can be curved within the width of the bridge's track bed.
If you use curved spans, as Gerhard did, you want the track on the curve inside, so it stays between the bridge supports and the train doesn't tilt the bridge off the piers. :laugh:
Lovely kit, and well built, well done, Gerhard; - shame it is not prototypical (for the engineer it's not just the curve, but the rivets and the gusset plates are missing too, i.e. structurally impossible).
My favourite bridge manufacturer: Micro Engineering; structurally correct, i.e. prototypical, and detailed at a level you have to see to believe; - makes all others look like coarse toys. And comparatively cheap, considering their excellent quality.
Just an observation, added belated, but for the benefit of those reading this thread.
Cheers
Waldschrat
One example:
http://www1.coe.neu.edu/~jfhajjar/home/Curved%20Girder%20Bridge.jpg
There are more if you do a search "curved girder bridges"
Fair point, I should have said 'railway bridge'. On road bridges the 'load', i.e. cars, are a benign weight compared to the weight of the bridge. This is not the case for railway bridges, i.e. the road bridge in your linked picture will collapse if you run a train across it (even if it were strong enough for the weight as such). ;D
The other aspect is the radius: our radii in model are much tighter, which aggravates the structural problem; so, yes if you were building with accurately scaled radii you could use curved bridges, but not with the tight radii we have.
Last, not least, if you looked properly at your search the first railway bridge that comes up (in image mode) is already a point in case, i.e. a polygon with straight spans. And the only curved girder railway bridges that come up, are all model railway bridges. All railway bridges have straight spans. So, please don't compare apples with pears. ;D
Cheers
Waldschrat
Quote from: Leprechaun on February 01, 2019, 12:08All railway bridges have straight spans. So, please don't compare apples with pears.
Do you a decent underside view of this bridge to confirm one way of the other?
https://www.alamy.com/lunz-am-see-train-of-ybbstalbahn-ybbs-valley-railway-at-trestle-viaduct-hhnernestviadukt-in-hhnernest-mostviertel-region-lower-austria-austria-image209237266.html
http://cs.trains.com/mrr/f/11/t/211826.aspx
There's also this, more recent one which appears to be curved...
https://www.waagner-biro.com/en/divisions/bridge-construction/references/reference/railway-bridge-rafsanjan
Sometimes dangerous to say things are black and white, the railway world has a nasty habit of proving us wrong... Railway engineers would appear to have tried most things at one point or another!
For starters I didn't say black or white, I said I haven't seen one. ;D
So for the first bridge of your links, the H
Quote from: Leprechaun on February 01, 2019, 21:36
For starters I didn't say black or white, I said I haven't seen one. ;D
You didn't. You said "ALL" railway bridges have straight spans. That isn't the same thing.
Without further info on that second one, as all photos i can find show it the same way, curved, i shall leave you too it. Thanks for clarifying the Ybbs one, I thought it probably was straight but couldn't see any other photos in the Google search I did showing the underside so show it one way or the other.
No problem, for the 2nd one you can just look through the offerings from Micro Engineering, it's all online! Very nice stuff they have. ;D
Happy hunting
Waldschrat