Question re: Bachmann 46723 up and over trestle

Model Railroader Layouts and layout building
1

In my n-scale layout I had installed one of those up and over trestle kits you can pick up for a few bucks. I’ve had it installed for some time now and after completing some grade checks it seems as though the grade is steep. Not so much that a train with 5-6 cars has trouble but if I load up a train with 10+ cars the engine slips a bit.

I thought I kept the instructions but I must have thrown them away. I’m looking to see if anyone knows the spacing of the truss’s. If I recall it is supposed to be about every 3". Anyone have one of these kits or maybe the instructions and toss that bit of info at me?

I’m not looking for what is “correct” but what the instructions had written.

2

On my original HO trainset of I’m Not Willing To Admit How Many Years Ago (OK, mid-70s), the trestles would be placed about every 1/2 of a track section, aka about every 4.5" if on a straight, or 4.7" on a circle. It is very similar to this set on Walthers:

Walthers 433-8202

That has 13 risers, which run just over half-way around a circle, or around 6 18" circular track sections, so every 1/2 track section is about right.

I think that came to a grade of roughly:

3" rise / (13 segments * 4.7") = 23%

Yeah, that’s steep. [:)]

Brian Pickering

3

Thank you for the response.

This is N scale so with the info you provided I am able to calculate this:

1.3" rise in 24" = 1.3/24 =.054 = 5.4% grade

Now the next question is 2/3rds this grade is going along 11" radius track (Atlas 2520’s). What is the calculation to add to this formula to determine the “virtual” grade increase caused by the radius?

Anyone willing to bite on that one? :slight_smile:

4

Glad you were able to take the info to get the correct grade in N. I was mainly using the HO as an example of just how severe these trestles are (plus the very non-prototypical lack of support between trestles).

According to Trains Magazine, the compensated grade is another .2% to .3% addition.

5

Somewhat unrelated to my original question but something I was curious about.

I’ve read a couple times now that the over and under tressle is “toy like” or “far from proto…”, etc etc.

What product would one use to increase the grade through an area that you want to be able to “see through”.

I’m using this up and over tressle kit because I have a coal mine that sits behind the track that is graded and I don’t want to concele(sp) the coal mine by using foam, wood, etc. I want to be able to see through the track so-to-speak.

What would someone use in place of the up and over tressle kit?