Layouts and layout building

quick history: Me and my dad (i'm 19) started our layout in our basement in 1998... when i was in High School it sat reasonably dormant due to school and a time consuming job my dad had. Basically it was the first layout for both of us, so it had lots of typical beginner mistakes (insane grades and messy track laying). so recently with my dad practically retired and me an architecture student who needs to keep modeling skills sharp between semesters, i've come back to model railroading. with the recent acquisition of a Bachmann HO scale Acela train set, the layout has been undergoing some serious overhaul in order to run the Acela cleanly. So i've decided to make the 22" radius turns on the mainline banked... so i was wondering if there were any tips or tricks on how to do it.? [All track is Atlas CODE 100]

Which method of achieving superelevation is best is somewhat dependent on how the track was originally laid.

If the track is simply laid on a flat surface, with or without cork or other roadbed, it's probably easiest to shim under the outer rail.  Don't overdo it - in HO, one millimeter is plenty - and do taper the entrance and exit over at least two Acela carlengths.

If the track is laid on a narrow cookie-cut subgrade elevated on risers in the classic L-girder configuration, it's possible to twist the subgrade and avoid the shims.

If you have decided to go whole hog and incorporate spiral easements, the superelevation begins at the point where the easement meets straight track (the actual point of tangency) and reaches maximum where the easement becomes a fixed-radius circle (the actual point of curvature.)  This is true no matter which method of superelevation you adopt.  It's also true regardless of the brand of track or code of rail.

Chuck (Modeling Central Japan in September, 1964)

As Chuck has said the easiest way is to raise the outside rail.  I have seen that done with a strip of 1/32 balsa wood, with .040 plastic strip or layers of msking tape. 

Maximum superelevation on the prototype is about 6", which is .066".  I would stick with something less, .020 to.040 would be good (that's about 1 3/4 to 3 1/2 inches).

 

 be careful when you start this.  the DRGW had serious problems with the track on their south route through the rockies.  if they used enough super elevation to get the passenger trains up to speed, they had a problem with uphill freight drags "string lining" on the curves. 

grizlump

 Think an easy way if track is already down would be to insert some wire along the outside edge.

 

Bill D

My preferred method with track already fixed in place has been to break up any ballast, or slice through any glue with a blade, and then pry up each tie and slip a small sliver of card stock under the end of the tie, but it should be long enough to actually lift the outer rail a bit, say 20 thou or 30 at most.

This takes time, but it works well.  One thing to avoid, though, is overdoing the superelevation. It sometimes fools us into thinking it isn't enough, but when you take photos of an engine or a train on the curve, it looks uncomfortably overdone.  A little superelevation goes a long way and looks good.

-Crandell

HFD 147:

with the recent acquisition of a Bachmann HO scale Acela train set, the layout has been undergoing some serious overhaul in order to run the Acela cleanly. So i've decided to make the 22" radius turns on the mainline banked.

 

You do understand that, in HO scale, superelevlation with have no effect on the performance of the train, right? (Well, excessive superelevation can have a negative effect, but that's not what I meant.)

If you are having derailing issues or the like, you have a problem that superelevation cannot solve. 

 

 

I use 1/8" wide strips of 1/16" cardstock up to 36" long (cut off of matteboard or something similar) and tapered for at least a foot at each end.  My main line turns are 33-36" radius so this may not apply to your situation. 1/16" = 5.44 scale inches of superelevation.

Karl.

Midnight Railroader:

You do understand that, in HO scale, superelevlation with have no effect on the performance of the train, right? (Well, excessive superelevation can have a negative effect, but that's not what I meant.)

If you are having derailing issues or the like, you have a problem that superelevation cannot solve. 

Thanks guys... very helpful information. I had removed much of the mainline in order to fix the MANY problems i was having with most of my locomotives, most of it is now back down but i figured super elevating the curves would be a nice ascetic touch. The Acela is simply what prompted me to renovate the track work.

Thanks again.

-mike

I had my track laid before I read about superelevation.

I took an old deck of playing cards, cut 4-5 mm strips on the short side.

Started with one shim and added up to 5 at the peak until time to go back down.

 I use playing cards for all kinds of building.