Need help with dimensions on ME bridge track

Model Railroader General Discussion (Model Railroader)
1

Hi,

Pretty much as the title says, I’m building a trestle and I want to use the ME bridge track for it. But I would need to know the exact dimension on it. Walthers doesn’t say and I haven’t been able t find the info anywhere else either.

This is the product.

http://www.walthers.com/exec/productinfo/255-11101

2

What dimensions are you looking for? Do you just need the overall height of the ties and track, or do you need the individual measurements? I have a couple pieces of the bridge track that came with the Micro deck girder bridges. I can measure these up with a micrometer if you think that will do it for you.

3

Hi,

Thanks for the help, I really apreciate it, what I need are the dimensions of the height of the ties and the width of them, that is how wide the entire tie is from left to right. I need the info to calculate how wide the trestle have to be.

Magnus

4

The M.E. bridge ties are .100" thick and 1.365" wide. The ties will overhang most deck style bridges somewhat - about .150" on both sides of the M.E. deck girders. The support structure of the bridge (the span members) should be under the rails, not necessarily under the ends of the ties.

Wayne

5

Okay, the sample I have is a 6-7/8 inch section of track from the Micro Engineering 75-520 Thru Girder Bridge.

The height of the rail is 0.083 inch. The thickness of the ties is about 0.105 inch. The height from bottom of tie to top of rail is about 0.183 inch. (You would think that the first two dimensions would add up to the third, but they don’t. There was some variation on the thickness measurement depending upon where I measured, but the numbers are probably close enough for what you need.)

The left to right width of the tie is about 1-3/8 inch.

I am assuming that what they put in the girder bridge kit is the same dimensionally as the long individual piece you referenced from the Walthers catalog, but you’ll have to decide that for yourself.

Regards and good luck.

6

Thank you very much both of you. This helps me tremendously as I start constructing the jig, now I know the width that I need to build it in.

Thanks,

Magnus

7

Magnus,

The top of each of your bents for the trestle should be approximately the width of the rails. Regardless if the trestle is straight or curved, this is the dimension to use. If curved the beam/ girders are sectioned/ mitered at each bent. There is always tie overhang.

Don’t worry about the height/ tie thickness at this time. It only becomes critical when time to install the bents and abutments. A hint for installation: Allow the rails to continue out past the abutments and onto the standard flextrack. Pre drilling and spiking them will allow a smoother transition to the trestle and also help in anchoring. Rail joiners could be used at this point if desired, but I don’t like the look of them.

8

Thanks for the aditional info Bob.

I’ve been looking at a lot of different plans. It seems to me that the style varies quite a lot including if the ties protrude beyond the top bents or not? How was it on the B&O, did they have a specific style?

I’ve kind of guessed that this varies a lot depending on the railroad and what standard they use. Trestles seems to be lacking in standardization, except on a few things that they all have in common of course. But, I’ll be the first to admit that I’m NO expert so I’m very glad for your input.

Good ideas about letting the rails continue, I’ve done that on previous bridges and it really helps to make a smoother transition.

9

I’m not sure that I agree with this. I have the Bridge and Trestle Handbook by Paul Mallory. There are several prototype trestle drawings shown. The bents are the vertical part of the structure. The book calls the horizontal member at the top of the bent a cap. There are stringers that span from bent to bent, resting on the caps, which support the ties. In one of the examples shown there is a pair of stringers under each running rail plus an additional stringer near each end of the tie. In another example, there are three groups of stringers. These support the tie in the middle, plus each end of the tie just outboard of the running rails.

In both of these examples, the ties do overhang the stringers. However the caps are longer than the ties, in the first case by two feet, and in the second by three.

There is also a drawing of a ballasted floor trestle if one were to be so inclined. These have more stringers. In both drawings shown, the caps are 16 feet long while the ties are the typical 8 feet long.