I have to say that, after reading all of the replies to this thread, I have no idea what this thread is all about.
It seems to me that the original point of this thread was that river beds are not all level. OK, granted, but thanks to gravity (or whatever) the water surface appears level most of the time. So, what is a modeler to do other than to make the river bed level and depict the water surface in the same way?
Rich
Alton Junction
richhotrainI have to say that, after reading all of the replies to this thread, I have no idea what this thread is all about.
Yea, really. Just one of TF's "philosophical moments"
We all understand that water runs down hill. Watch a floating leaf drift by, or toss a fishing line with a bobber in a river, even though it can look like still water, and you'll get what's happening.
I think as modelers, we depict river "grades" with water falls and rapids, to give the feel, or illusion of running down hill, even if the surface we started with is level.
Mike.
My You Tube
hon30critterThat's not quite true here in Canada. Both spellings are acceptable.
Not as far as I'm concerned! I'm also getting fed up with Canadian newspapers and magazines, along with on-line posters that are too lazy to choose their preferred language, simply accepting a U.S.-based spell check. I mean, really, they can't even pronounce zed, then put zees everywhere where an ess is perfectly serviceable. All in an attempt to make it rhyme in the A-B-C song, I guess. Ha-rumpf!!
richhotrainI have to say that, after reading all of the replies to this thread, I have no idea what this thread is all about....
I gotta agree with you on that, Rich, and I probably should remove the pictures from my earlier post....they seem inappropriate to the conversation.
Wayne
PRR8259 Track Fiddler-- I'm sorry; I don't remember the post, but I was offering an opinion only. John
Track Fiddler--
I'm sorry; I don't remember the post, but I was offering an opinion only.
John
John, I am a man of karma. Your apology is very much accepted. I have to apologize too. I was a little blunt that night.
We are all good here.
TF
Friends
I couldn't find it but somewhere along the line you said you thought posting all your pictures was unappropriate.
You thought wrong. Everytime I see pictures of your work I admire them.
You just leave your pictures here and I will continue to admire them
If you look up River in the dictionary I think the pictures of your work should be there
USGS topographic maps have been one of the best resources to study railroad and waterway grades for more than a hundred years.
https://www.usgs.gov/products/maps/topo-maps
Here's a tiny corner of a map including Horseshoe Curve. Lots of information concerning land use and waterways, including elevations are available for free download at USGS.
Hollidaysburg, PA, 1:24,000 quad, 1963, USGS by Edmund, on Flickr
Each thin brown line represents a change of twenty feet of elevation, heavier line is 100 feet.
Which river or geographic location are you looking for?
Good Luck, Ed
I'm not an engineer, but I live in Eastern Canada where there are tons of lakes and rivers. From what I have seen, all rivers involve slopes since there is "current" - otherwise they would be lakes or oceans. But slopes are not all the same simply because terrain is irregular. The slope will impact the surface of the water, going from an almost flat looking surface (when no wind is present), to something like the Niagara falls. Between these two extremes, water is more or less irregular in appearance, depending on the slope. What also affects the surface is the depth of the river, the quantity (flow rate) and what is under it: rocks under a thin surface will create rapids. Colors also change because of the mixed air content that increases with the slope... Water is such a cool thing but so hard to model...
Simon
I stand squarely with PRR8259 on this, both philosophically and technically. But just for fun I'm gonna cloud the water, so to speak, a little more.
Flowing water exhibits two nominal characteristics: sub-critical and super-critical. In sub-critical flow, the surface of the water is flatter than the river bottom; and in super-critical flow, the surface is steeper than the bottom. Super-critical flow causes the water to accelerate and stretch itself out until the surface tension breaks and the mass falls apart (whitewater), or until it encounters flatter water and creates a hydraulic jump (ripples, waves, eddies, and so forth). Along with this activity, and for other reasons as well, the physical shape of the river bottom is eroded into a series of riffles, runs, pools, and glides. All this is an oversimplification, of course, but this is a model railroading forum and not a hydraulics classroom or a fly-fishing training camp, philosophy notwithstanding.
Now, back to modelling. That structure ain't gonna scratch-build itself.
Robert
LINK to SNSR Blog
It is hard for practicing engineers on model forums I think, because we want to be helpful, in not too many words, and we sometimes try to explain concepts that are just not "easy"...subcritical versus supercritical flow--that's half of a college fluid mechanics class right there. I found that challenging and drifted more toward 3D geometry...
I love the model pictures above. I lack the time and patience to do that on my current layout. Maybe once the kids are gone, and I find the next, smaller, house (a ranch with full basement and walkout glass doors to allow access from outside once some of us can't handle steps) I can try that.