So the new layout under planning has a port area based on various ports i hav ebeen studing. reallt is hard to fit even a scaled down selective compressed one. in this plan is an inlet. which has to be crossed by a lift bridge. or temporary lift plywood in the mean time til this is done. figuring a couple years. I have been looking at these bridges and found on the cuyahoga river cleaveland by route 90 is an NKP double track lift bridge that is a good match for the location on the ayout. Google and bing tuened up a few pics and a few tidbits. but nothing I can work with ibn the way of drawings with dimensions. alll the pics are from a distance. an not very clear for designing a model after. mine will be slightly more generic. any place with better pics or data or prints of this bridge? I did find a measured drawing of PRR bridge 458 over the calumet river. but htat is smaller and skewed.
Surely there are measured drawings of a Scherzer (note sp.) rolling lift bridge somewhere in this community!
it was my naive understanding that most of the load-bearing structure was the same as a bascule bridge. The difference is in the rolling sectors on tracks that substitute for hinges, and the corresponding provisions in the counterweighting (which aren’t as critical on a model).
This might also simplify what you’d have to print to ‘kitbash’ an existing bascule design or kit.
I scratched and bashed that bridge 6yrs. ago and did have a small thread about it here on MR. Some that have answered You may not have seen it’ It is not an exact replica but close. I built it for a section on the layout that had a low ceiling, so the counter weights are a little shorter. I started with a double track truss bridge from Walthers and everything else was scratched from Evergreen shapes and Central Valley… I got all the dementions I needed from this info from the bridge using an HO scale ruler:
OK this isnt a scherzers. this wa as lesson in hunting online and hwo some dont tell you the whole story. In this alignment prioor to this parker span high level verticle lift bridge, was a 167 foot scherzer. when the scherzer was weak, this was decided to replace it. thing is, the river and bridge had heavy traffic. shuttin down for long periods of the river and rail was not in the game. the lake traffic died between dec and april giving some window. original plan was to take the scherzer span, reinforce it and modify it to be the center span while it was in service. this is where the sites stopped. they failed to say was that didnt happen. The scherszer was 100 feet to short for this design and couldnt be modified in service. to much stress would be imparted from the added wieght to keep it working before being lifted up to be the center span on this one. So the parker truss span was built instead. that is where I got the scherzer part from. and the research lesson.
Thanks to Engineering News Record, they had an article on the construction of this bridge. I now know. this is NKP bridge 184. And that it is a parker truss high level. The concretr foundation piers are poured aroud the scherzers piers. 10x13, width wise at 33 foot center and longitudinal 46.5 feet. matches the main colums of the tower giving me the tower diemsions. it also listed the towers as 150 from pier top to axle for the sheavs. with the parker truss at 267 footlong and a track centerline spacing of 12.6 the verticle track clearence is the only thing I dont know. everything else I can extraplated from what i have. The space the centerspan will fit on the new layout will be a two foot span. still imp
I don’t think the text has changed, but my understanding of what he wants certainly has.
I initially took the ‘lift’ in his question to refer to that phrase ‘Scherzer rolling lift bridge’ – since he quoted the bridge type by name. However, I had a sort of Han Solo uneasy feeling about this, and the comment about PRR bridge 458 made this spill over into research this morning.
Bridge 458 is a Chicago landmark – and very much a vertical lift bridge with openwork towers. There are even pictures from ~1915 that show how the central lift span was built, on falsework cantilevered out from the towers, perhaps a response to the difficulties with the Quebec Bridge construction.
I’m certain there are 3D files for different types of lift bridges, and I know several people on this list have built them and probably know the pitfalls and ‘tips and tricks’ to make one… especially one that allows human access to part of the layout.
I dunno, I’ve been able to follow along (the spell-check has been a bit of a head-scratcher, though). The process of designing stuff often goes off on a tangent every once in a while. Free flow of ideas and whatnot. Particularly in proto-freelance model railroading. And also particularly when melding and merging two different, but similar, styles of bridge. Either one, in its purest form, would be perfectly suitable; but I would also enjoy a thoughtful hybrid amalgamation.
It wasnt much of a situation of going on another tangent. more of a learning abou t the object in question. in this case, google put up a bunch of sites that were not good informationally. but not knowing that until finding an engineering document that proved the first site didnt have the right info. so I was able to correctly identify the specific structure propperly. good reason to do alot of research when working on something. Verifying the info already found. I would have been interested to see a finished resault of a modified scherszer reused in the high level. as it is bridge 184 is historic. this 403 forbidden is really bad for me this time and very intermittent
A few years back, I scratch built, well kit bashed/scratch built, a vertical lift bridge using three Walthers Arched Pratt Double Track Bridges to build the main span and Central Valley parts to construct the towers. I chose to make it non-operational. I modeled the bridge based upon the PRR 458 Vertical Lift Bridge that crosses the South Branch of the Chicago River at Canal Street.
I ran a thread about the construction of my model back then, but Photobucket destroyed it by removing all of the photos during one of their fee tirades. Here is a photo of my finished model.
The vertical lift bridge that the OP is considering is different than mine in several ways but mainly in the shape of the towers which are more similar to Frank’s model.
Walthers has produced a series of bridges including swing bridges and bascule bridges, but to my knowledge has never produced a vertical lift bridge. Custom Model Railroads (CMR) has such a model, like the type that the OP is contemplating, but it is quite pricey.
