Large Scale Central

Question: Do Guard Rails Work for Real?

Track and Trestles
#1

Okay fellas, I got a question with real implications as opposed to a hypothetical: Do guard rails on our model railroads actually serve the same function as the big railroads? I’m asking this because I’m cautious about getting my dormant upper loop running again, dormant because on the last run a car or something caught on one of the curves (20-ft dia.) on the track, pulled on the whole train, and my big beautiful three-truck Shay went crashing six feet to the ground…BOOM! Fortunately Kevin was able to fix it up; which is really good since our friend in Philadelphia has long since retired…I sorta miss his involved analysis and long lectures on making sure I never let THAT happen again.

So I want to get the loop running again, but I don’t want to take the time, right now at least, to install guard rails unless they will prevent derailing and another BOOM! I’ll get to the cosmetics later if that’s all guard rails amount to on our models.

Thanks.

#2

" Rooster " said:

Well, that certainly answers that question!

edit: Wait a minute. I just figured it out: David is the reincarnation of Calvin Coolidge.

#3

Yeah, but it’s hard to argue with! (http://www.largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-tongue-out.gif)

#4

First of all, and no-one can argue, that your railroad, and how much fun, and enjoyment you will get out of it, is only as good as your track, and the stability of the roadbed under it.

This also applies to the real railroads, although “Fun, and Enjoyment” is replaced by just “Safe operations”

Guard Rails, on bridges, and also, sometimes on curves, do not replace good roadbed, and trackage, but are used to back up the safe guidance of steel wheels on steel rails. If properly installed, guard rails do prevent derailments, and should not be considered as “Cosmetics”.

Of course the dynamics of wheel to rail performance depend on certain standards, whether in model or prototype operation, and must be maintained for safe operation. Wheel, back to back gauge, and rail gauge must be properly maintained, for successful, safe operation.

If your major derailment happened on a curve, or in fact anywhere, even on a tangent, and everything was in gauge; then I’d look at the level of your track, not as to the grade, but to the level across the gauge.

People often seem put out when I comment on the lack of guard rails on bridges. But guard rails do serve a purpose that is most important to the protection of structures, and the equipment operating on them. The real railroads would not waste their money on them, if they did not serve a reasonable purpose.

Fred Mills

#5

but but but … I was taught that the guard rails on bridges are for after the derailment. Their purpose is to keep the cars/train on the bridge by preventing the outside wheels from going off the ends of the ties.

John

#6

Guard rails on bridges perform a similar function to guard rails on switches, but not quite the same function. Guard rails on switches keep the wheels from picking the point of a frog by preventing the wheel from being able to move laterally in the open part of the frog. They do this by rubbing against the backside of the flange should the wheel get to where it comes in contact with the guard rail. The gap between the rail and the guard rail is not very wide–less than 2". It is also the same height as the rail, as it has to be able to contact the flange when the wheel is on the railhead.

Bridge guard rails are not there to keep the wheels on the rails. They’re there to keep the wheels on the bridge should they come off the rails. Bridge guard rails are located much farther away from the rails. (The Baltimore & Ohio RR standards dictate a 10" gap.) They may or may not be the same height as the main rail. Often bridge guard rails are built from smaller, lighter rail.

On our models, the guard rails (properly installed) would perform a similar function–to a point. They would definitely keep the wheels on the bridge if they were to hop off the rails. However, they cannot prevent a car from rolling over. On an elevated track, the guard rails aren’t going to do squat if a gust of wind catches a box car and pushes it over.

I think in this case, a better safety feature would be some level of retaining fence along the edge of the elevated track. It needn’t be much; I could see it being done with 14-gauge copper wire about 1.5" high supported every 12" or so. That’ll stop a train from falling off the edge the same as a guard rail would, but would also catch any rolling stock that decided to roll in a direction other than the proper one.

Later,

K

#7

I have wooden guard rails on most of my bridges and trestles. They do keep derailed cars from getting into too much trouble on the bridge.

#8

Thanks guys for the explanations…I didn’t know guard rails were for keeping the stock on the bridge, not to prevent derailments. I want to keep my locomotives on the elevated track/bridges. It may also come to the retaining wall Kevin describes, boo hiss. Pictures to follow in a few weeks.

Fred’s sermon on trackwork is well taken. It needs to be in a model railroad prayer book somewhere. Thanks again.

#9

Some mono filament fishing line might be harder to see… but I’d go for proper track flow, no kinks and/or jerky motion. I’m planning an elevated curved trestle and there won’t be any water wings (http://www.largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-wink.gif). Of course it won’t be 8’ high, but 6 pounds and a foot can alter plastic just fine thank you. (http://www.largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-cry.gif)

Always happy to enlighten.

John

#10

If your era would allow it, you could use a though plate girder bridge. The kind where 1/2 of the side plate extends above the rails. That would prevent a dive if there were a derailment.

But I do have to concur with Fred. I have yet to have anything dive off my curved trestle. Yes, its only about a foot or so off the ground, but its still a trestle, without guard rails. Proper wheel gauge, properly working couplers and decent track-work, has prevented any mishaps on my trestle.

#11

This is the Goat Canyon Trestle, sometimes called the Corrizo Gorge Trestle, on the San Diego, Arizona and Eastern Ry Co. Here, the guard rails are on the outside of the gauge, and are made of wood.

#12

Steve

That is called a Guard Timber. Its purpose is maintain the spacing of the ties on the bridge. Should a wheel derail it would not do much to hold the truck on the bridge.

John

The suggestions for some form of retaining fence is likely a very good one.

One thing to look for on your track is the joints between rail sections Often there can be a slight misalignment that can pick a wheel and cause a derailment. Doing a slight grinding at each rail joint, especially on the outside curve rail can help prevent derailments.

Another idea is a third rail along the inside of the curve to help keep the wheels away from the outer rail. These guard rails are normally much closer to the rail than a bridge guard rail and have the purpose of trying to keep the wheel on the track rather then preventing a derailed car from falling off the bridge. On the prototype there is often an oiler at the beginning of the curve.

The C&TS used to have these on some of the tighter curves but most if not all are gone.

Stan

#13

Thanks very much for that, Stan. I’ve been working for a bit every night on that elevated loop trackwork on all the things in Fred’s prayer book. Come to discover, when I really looked closely, my trackwork was truly a freaking MESS. Your idea of a third rail is a good one, and together with a wire fence like Kevin describes, seems inevitable.

On aligning the joints: in cleaning up my trackwork I discovered that if I take a pair of flat pliers, place it holding both ends of the track joint, and twist in the right direction, I can bend the rails into perfect alignment. When the height of the rails is off, it’s because the bed underneath is off, so I fix that instead of the rail itself. I try not to grind because it’s so permanent.

(Of course the exception is that you have those pathetically defective, aggravating, exasperating Aristocraft switches that pick everything in sight. It’s the Dremel and grinding disk for them. I don’t know how a manufacturer gets away with selling such a product; I’d be out of business in three months if I put something like that out on the market.)

#14

They CAN be made to work well, normally just fixing the guard rail flangeway widths and setting your back to back, 99% of the issues go away.

One of the first things I found out in my railroad, which is all Aristo track.

They all work flawlessly now.

Greg