curves and track design

[jowalmer]

Someone here once posted information on combining different Bachmann turn radius track to make a curve that enters and exists gradually.  I did a search but couldn't find it.

I currently have 2 lines one uses 22"  curve radius the other uses 26".  To me, it doesn't seem realistic to have the trains running straight then into constant radius turn.  I would also like to explore making the curves a bigger overall radius by utilizing the 22" and 26" radius track I already have (to reduce cost).

Lastly, I'm interested in finding track design ideas that will help me understand how to take one line and double its length (more or less) by inclining the track and crossing over itself then back down again.  I'm using the bay of a single car garage; all its width and just a little more than half its length.

Thanks.

JIm

[Jerrys HO]

Jim

I found that putting a short straight 2 - 4.5 in between the curves and when doing S turns especially in between the S helps with the longer rolling stock making it thru with no problems.

I use anyrail.com to design most of my layout. I have a figure 8 inside my outside main line with 2 reverse loops off of the figure 8. The figure 8 is an over/under with a 2-3% grade.

Jerry

[Doneldon]

Jim-

Transition curves, or at least ersatz transition curves, are easy with sectional track. Depending on the available space, make the first and last section of a curve with a piece of track which has a radius one step broader than your main radius for the curve. If you have a ton of space, you can use a two-step more gentle section for the first and last sections, and one-step more gentle sections for the second and next-to-last pieces. Although it can get pretty expensive with sectional track, you can use half- or third-sections for your transitions and get the same effect without excessively changing the overall radius of the curve. You won't get true transitions because they aren't a spiral track, but they will improve operation and appearance. It's probably best to fiddle with your track arrangements until you get your curves to start and end where you want them to. That's because curved sectional track uses different numbers of pieces to accomplish a full circle, meaning the degrees of curve vary among the different radius curves.

True transitions are even easier with flex track. Just begin curving your track and  it will arrange itself into a transition unless you impose a particular curve on the track.

An over-and-under track is basically a figure eight folded over itself. You can ease the grade by starting a track up from your base level in one direction while the track goes below grade level the other way.
                                                                            -- D

[jowalmer]

Thanks guys.

@ Doneldon.  You are on "track" with what I'm looking for...but more specifically, I'm looking for the post where poster gave specific info on which radius and curve track length combinations result in 90 degree turns.  It was very informative...I just can't find it now that I need it.

[Jerrys HO]

Jim some who post here have their post set to delete after a short period.
I know which one you are looking for I will search to see if I can find.

Jerry

[jowalmer]

The figure 8 is an over/under with a 2-3% grade.

Jerry

@ Jerry.  With the 3% grade in your figure figure 8, how many cars can a single loco pull up the grade?

[Jerrys HO]

Have you seen this post yet?

http://www.bachmanntrains.com/home-usa/board/index.php/topic,18203.0.html

It pretty much depends on the engine. All of my GP's have no problem.
I have already had 14 cars behind my GP40 which came out of my Digital Commander set. My 0-6-0 struggles with a little slippage with more than 3-4 cars as I need to add some weight. My MTH SD70 can virtually pull anything.

Jerry

[Jerrys HO]

Jim I believe I found the one you have been looking for. It was posted by Joe Satnik.

http://www.bachmanntrains.com/home-usa/board/index.php/topic,6564.0.html

http://www.bachmanntrains.com/home-usa/board/index.php/topic,8875.0.html

[jowalmer]

Jerry...u da man!  That's the post I was looking for. 

I also looked at the link you posted in your previous post to the previous post were it suggested to alternate 22" and 26".  I see the logic and since i have the track, I'm going to try it to see how it works.  In fact, it wouldn't have to alternate; one could simply place the 4 22" in the middle of the turn and lead one side with 3 sections of 26" and the other with 2 sections of 26".  I'm not looking for perfect concentric turns but to come back to parallel.

Now on to the 2nd part of the original post.  At 3% grade, how long does the track have to be to get the height to cross over itself??  Is there a formula that can be used to determine the length of track needed to achieve a set height using a given grade?

[Jerrys HO]

Grades are calculated by each inch of rise per 100 inches of travel. A 3% grade would be 3 inches of rise for 100 inches of travel.

I used the Woodland Scenics risers on mine. They have different grade risers and  I used the 3% grade. I did modify the grade to stretch it out further by cutting the middle section and adding a straight length of between the two.

I have my over /under height at 4" which is a little higher than some but I wanted to make sure all my rolling stock will fit.

Jerry

[jowalmer]

Thanks Jerry.  All questions answered.  Have a good one.