Flimsy bridge?

[Anonymous]

Torby got me thinking about this...

If you can make the section of track just for the trolly, and depending how long the bridge ~CAN~ be....

Then cut track sections just a little longer than the trolly.
Devise a simple way of mounting a pivot in the middle of each track section............
you're making a teeter-totter that rocks back and forth.
You will have to limit the amount of movement and may want to have a small counterweight to keep the "entrance" section at the "exit" level.
As the trolly goes over the fulcrum point, the trolly's weight makes the track rock down to the next section where the same method is used.
Have several of these teeter-totter sections in a row for a wild, rocking ride.
If using track power, each section, of course, must have its own power feed.

You can hide the mechanism by having a high curb at the bridge deck level.
You could also make this deck curb wavey , distorted and deteriorated, in an up & down fashion to enhance the illusion and partially hide the workings behind it when viewing from the sides.

FWIW

WB

QUOTE: Originally posted by Torby

[2c]I think I'd build it ...

Give it a solid foundation and moving parts. A spring holds the "flimsy" parts up, and the bridge is built to look "straight" with the spring holding it up. When the train comes, it presses the moving structure down to its solid foundation, where it's meant to operate, and the moving structure, which is just decorative, is out of place and distorted, making it all LOOK like it's about to fall down, but is actually on a solid structure.

Disclaimer: I've been thinking about this since the initial posting, but I haven't followed the thread[:-,]

[Tom The Brat]

STOP
PAY TROLL

[Ray Dunakin]

Cute idea, and a very cleverly designed bridge!

[Anonymous]

Below are two photos of a suspension bridge I recentlly built; it looks flimsy, but it's an engineering marvel, as anyone can see. I would trust my best engine on it. As you can see in the second photo, a family of trolls as built a home under the bridge and now regulates passage as a troll bridge.

[Tom The Brat]

[2c]I think I'd build it ...

Give it a solid foundation and moving parts. A spring holds the "flimsy" parts up, and the bridge is built to look "straight" with the spring holding it up. When the train comes, it presses the moving structure down to its solid foundation, where it's meant to operate, and the moving structure, which is just decorative, is out of place and distorted, making it all LOOK like it's about to fall down, but is actually on a solid structure.

Disclaimer: I've been thinking about this since the initial posting, but I haven't followed the thread[:-,]

[GP-9_Man11786]

Drive on the New York State Thruway and you will see plenty of flimsy bridges, the Tappan-Zee being the most obvoius example.

[Capt Bob Johnson]

Took a steel stud and screwed some SS track to it. Cars and engines are wider than the bridge. even looks scary. put a rerailer at each end to be on safe side!

[ttrigg]

rtstasiak

The intended "cargo" will be limited to a single trolley car, on an auto reversing straight track. There might be an occasional "tourist special" making the run up to the "hotel". Made a "test" run this weekend, 5 ft section scotch taped to the square steel and the "bridge" did sag a little as the trolley went up.

[rtstasiak]

Back in 1981 or so Model Railroader featured an HO layout with a deck truss bridge made with very very small beams but lots of reinforcing rods and turnbuckles. The point of the bridge was to bend, twist, and deform while a train went over it, but not to break. I think that the rails and ties did most of the carrying in this structure, so in G-scale heavy rail on the bridge would be a must. Otherwise, the beams, braces, etc. can be light if you're running plastic on electicity, or heavy if you're running live steam. RC / Battery and live loads of coal, gravel, and ethanol solutions would also shift you towards heavier members, but not as far as a hunking $4000 live steamer!

[Anonymous]

I know where there are several bridges that really should not be in existance; they are part of a discontinued railway line running alongside the New England Highway in northern New South Wales. They are all about 100 years old and made of wood and are falling down.
However the way for the rails; and even in places the rails are in place and it looks as though you could go right through it and make work again without much trouble.

rgds ian

[devils]

ttrig, yep like that one, you'll need compensation on the axles like a monster truck chassis to keep in contact with that! vsmiths cantilever looks nice too as a short end span.

[FJ and G]

VS,

Back in 1978 or 79, I visited a subway attraction at Universal Studios, where propane is used to simulate a fiery subway wreck. I think there may have been a movie associated with it.

[vsmith]

Dave
You could make the bridge out of steel welded together, and then use a propane BBQ burner along the base hidden in that BBQ lava rock they sell, just think, if your cleaver about how to feed the gas lines you could easily replecate the very sceen above with a propane flame! I would keep the flames along the bottom, to prevent the track ties from melting or just make a stretch of deck track with a fireproof insulating material between the track and the bridge undernieth... That would be a SCARY bridge [:O][;)][(-D]

[FJ and G]

Tom writes: "I want to "scare" the passengers with an apparent dangerous ride. I want the "wooden" bridge to appear as if it will fall any day."

This might do the trick. Just have a fire extinguisher handy before the neighbors call the FD.

[vsmith]

How about something prototypical??

This is a REAL bridge on the White Pass line, its a cantilevered suspension bridge...

[Anonymous]

That's a series of pics that is worth looking at. Some days it doesn't pay to get out of bed.

[Ray Dunakin]

I got a lot of interesting hits when I searched Google for "old trestle". Did another search for "wooden railroad bridge" and got a few hits. Here's an amazing series of pics that probably goes a bit farther than what you have in mind:

http://forums.t35.net/index.php?topic=971.new

:)

[tangerine-jack]

Right, 3 Stooge style it is! "Spread out you knuckle-heads, we gotta' build a bridge" "why soitenly! Nyuk nyuk nyuk!"

I would build it to resemble the photo, but make the deck flat for operation sake. A little optical illusion in contruction and you'll be fine.

[ttrigg]

Devils;
Thanks for the thought, what you think of this one?

Next question, How much left-right rotational twisting will a trolley take before it falls?

[devils]

OK lots of flat cars!!!!!!!!!!!!!!!!!!!!!! only kidding

Have you tried google - images search? Old bridge or wooden bridge? Look for New Zealand tramways, they had a timber line that ran along the cliffs on some real low tech wooden bridges. If I remember the name I'll return.

Less testle legs and some gaps in the deck should help the delicate appearance.

[tangerine-jack]

OK, very well. What about a glass bridge made from pexi-glass? Animal bones? Giligan Island style? Nothing at all but the steel supports? Southern style made from duct tape and Wal-Mart bags?

[ttrigg]

TJ:

The wife is reading over my shoulder, rope bridge has already been victum of the "veto pen".

I like the idea, but..................... got to obey the boss.

[ttrigg]

devils

The overall "real length" will be about 38 feet with an elevation climb of about 28 inches. Yes, that is rather steep, but that is the whole purpose, no long trains, no long cars, just "shorties", just the trolley line, and on occasion (after I make a few more purchase) a two car "sightseeing train."

[tangerine-jack]

There is a great looking bridge in "Indiana Jones and the Temple of Doom" that's made of ropes and crappy wood. Several of the type also appear in any Tarzan movie. I know it's only a foot bridge, but who says you can't use that as an inspiration for a train bridge? I know I would be hesitant to cross such a thing...................

You could easily make it out of well, ropes and wood. Should take you about 8 minutes.

[ttrigg]

John;

I've already sliced up two wrought iron gates for the square steel, plan to "hide the steel" during construction. Yes the plan is to build it "over strength" yet have it look weak. Was planning on just spacing timber bents "too far apart" and only using two posts per bent. She Who Must Be Obeyed , CFO of RbFSRy, Land Use Commissioner and mistress of all she sees has instructed me to find prototype weak and rickety bridges to fashion after. She has instructed me to "fashion" my bridge after one that did exist, not necessary to duplicate to "scale" but just capture the flavor. I have many photos of the Mount Lowe branch of the Pacific Electric RRy, and the Echo Mountain Incline Cable Cars, and their various bridges and structures.

The request was nothing more than "following orders."

[devils]

How about one made out of an old flat car, I've seen pics of those used for roads. Build it with a slight bow in it and leave it to weather down naturally, maybe stain the wood a bit with thinned black ink to age it, and within a year you'll have a real rotting bridge!

[:D]

[John Busby]

hi Ttrigg
Why not just build a good bridge out of steel using section that looks a bit small for a bit of a spidery look.
Then spray it with a good coat of charcoal and grey highlights to fake treated wood your passengers will not know it could really take a tripple header of
big boys and a two and a half mile long train[swg]
regards John

[ttrigg]

Anyone out there have a pic of a flimsy, wobbly and rickety old bridge? As I build the trolley line to the top of Rosebud Falls I want to "scare" the passengers with an apparent dangerous ride. I want the "wooden" bridge to appear as if it will fall any day. Don't worry, I've alread cut the squate steel tubing so it can be covered by the "rotting wood".