Grade

[Anonymous]

What era are you modeling? It sounds like diesel era. For that span length, the railroad would use a steel plate girder bridge. If you have adequate clearance under the track then they would use a deck girder arrangement but I think a through girder would look better. The problem is that a good model of a through girder is much more complicated to build.

Can you work with brass? If you know how to solder brass, then that is what I would use. You can get brass sheet and angles to make your bridge. A quality model in brass is going to cost you though. I am certain that a styrene bridge would support the load if you want to save cash or are not comfortable working with brass.

For a scale 88 ft span, the girder depth would be something like 11 scale feet deep. I guess that is close to six inches in your scale. If you use the deck girder, all the depth will be below the track. Sketch it up if you are thinking of going this way. If you are two feet above the ground (rail height) and the bridge hangs down six inches I don't think that will give you the look you want. A through girder will be about an inch and a half below the track and extend four and a half inches above the track. I think that would look better, but it will be more expensive and require more skill to build.

Give it a thought and let me know which direction you want to go. Good Luck - Ed

[Anonymous]

Funny you should mention that Ed. I have been tossing a few designs around and haven't really decided which type would A) Look the best and B) Work the best. I love those old wooden post and beams, but they are so rare these days I can't find any around here to go get a sketch of, plus a 2003 freighter just looks a little out of place on them. I have no idea where I could obtain g scale steel stock to build a steel truss bridge, so I am kind of leaning towards a good old concrete arch which I have already layed out in CAD. Looks like the bridge is going to be about 3 ft long and 2 ft high (scale 88'x 60' app). Some advice on which type would be welcome and some prototype designs by some rr CivE's would be outstanding. Oh yeah, and if you have some lying around, some Martian moon rock would be nice too.

[Anonymous]

My pleasure. If you want help with the bridge design, I know someone who can help. - Ed

[Anonymous]

Hi Ken...I didn't mean all 3 engines & 15 cars at once,on the 8ft. board, but I didn't explain it very well. Nigel,[below] has done a way better job of explaining it.
best regards / Mike

[Anonymous]

Nigel..this is WAY off topic, but do you know how Yukon, OK got it's name ?
Just looking out at our 6th straight day of snow here, and got curious.
Thanks / Mike

[Anonymous]

Thanks for the addtl' info. If you think of anything else, please post.
Bud

[Anonymous]

Thats a he** of an idea Ed, I think I will add that into my design layout and see what happens. THANKS!

[nfmisso]

Tough;

I would like to second the testing recommendation, in addition get a pull spring scale rated for a couple of pounds. Use the 8' long straight on a couple of 2x6 on edge, and 1" spacers at one end. Take each locomotive you have, and measure its pull on the flat, and grade in 1% increments until it is zero. Then take each of your freight cars, and measure the amount of force required to SLOWLY pull them up the grade in 1% increments. This will give you the approximate capacity of each locomotive, and the load that each car represents on a grade.

You may want to do this for every car and loco and keep the data in a form that is easy to access when you are making up trains.

Grades; I am in HO and did a similar test with several of my diesel (all wheels driven) locomotives, and found that they could do a 25 - 30 % grade by them selves, which is what you would expect from the coefficient of friction. One a 10% grade they each could pull several cars.

Clean your track before each session (see MR, Feb 2003 pg 102-105).

Good luck, and have fun.
Nigel

[Anonymous]

My gut feeling is that 7% is ambitious. Prototype roads sand the tracks and I haven't seen a model that will do that yet, but maybe that would be a good modeling challenge. I would consider attacking the problem from the other end. Can you raise the track at the garage end so that it leaves your garage wall at around two feet or so cutting the grade in half? I like bridges and I would build a fair length truss span to bridge the "walk through" area so you don't isolate a portion of the yard. You could lift the truss out and store it in the garage when you don't want to play trains. The truss span would also be a great modeling subject and when you tell people why you built the truss, they will learn something about trains and grades. Just my thoughts. Good Luck - Ed

[Anonymous]

I have thought about that quiet a bit. My problem there is this. This rail starts/will start in my garage where all stock and locos will be kept. It proceed through the wall across the yard and into the garden which also contains a grilling/social area. In order to give guests, and self the best view, the train needs to rise to the top of the 48" wall that defines the social area. It then circles the entire social area crosses a "creek" then the pond and around the "mountain". If I excavate the patio end to lessen the grade, the train would be out of view behind the wall. If I drop the wall, which also is the bench back, there won't be enough support to lean back on. I am thinking about just filling in near the wall of the garage and bridging it, thus isolating about 1/3 of my lawn, which I had hoped to avoid. Originally I was going to tunnel it. It is app 15-20 feet and some old timers have said I could never pull that kind of tunnel off esp, without having access to it. By the way, we just visited Virginia and W.Virgina (Natural tunnel State Park area and Roanoke area) and we are adolescently in love with the palce.

[Anonymous]

Would it be possible to excavate a cut for the right of way to extend the route and make it a lesser grade. I don't think you would be able to experiment with the grade on an 8 foot track board because your whole train, 3 locos and 15 cars, would be quite a bit longer than that. Keep in mind, if the route is curved the effect is similar to a steeper grade.

Ken, D&J Railroad, Stafford, VA

[Anonymous]

Tough198; do you already have the locomtives and cars you're going to be using ? If so, can you put about 8 feet of straight track on a board inside ? If so, you can test your equipment by blocking up one end of the board...each 1" you block up one end will equal about 1%. If you want to be exact, make it a 100" board.
Put the grade up until the wheels slip, then drop it down at least one inch. My guess is that you don't attain 7% unless you have specially weighted locomotives, but I could easily be wrong.
Good luck / regards / Mike

[Anonymous]

Correction to that. It seems I was mistaken on my grade percentage. My grade would be about 7-9 DEGREES not percent. The percentage would be more like 16. Obviously, I could never pull that off. If I could get it down to 7% would it could it work? Thanks again.

[Anonymous]

I am in the process of laying out a rather elaborate garden rail, probably a mistake for a first timer but education is expensive isn't it? My question, this time is one of grade. To my knowledge the steepest mainline is 7% (Saluda Mtn, Saluda NC) which is very steep. Is a G scale capable of such a steep grade with say 15 rolling stock and 2-3 engines? I have to rise from 0" to 48" over about 25 feet which gives me roughly a 7% grade. Any experienced voices on this would be greatly appreciated. Otherwise I will just have to try it and see.