Large Scale Central

Spline roadbed users/build question

I’m getting frustrated with my spline roadbed I built for my elevated layout.

I don’t know what I’m doing wrong but I’m ready to rip it all out for the 4th time and rebuild with the track attached to a solid piece of PVC or wood.

Here’s my spline. PVC strips with pressure treated 2x2 pieces spaced every few feet. The PT pieces are then screwed down to my benchwork and leveled crosswise. Everything is then backfilled with sand( this might be my issue right here?). The track is then placed on top and allowed to float as recommended. Every 6’ or so i screw down a few hand spiked ties with a washer and a screw driven into the PT spacers. In a few places I’ve directly pin nailed the ties to the spacers ( seems to work slightly better). Every single place that’s in direct sunlight I get massive vertical movement and track gaps as the track moves. Other places in direct sunlight seem just fine and don’t have nearly as much vertical movement. A section along my fence line I’ve had to rebuild 3 times ( every summer) and then once winter hits it’s all screwed up again.

What the heck am I doing wrong? I know this method has been proven over and over again.

Is the fact that I’m handlaid the track and the ties are are “independent” of each other playing a role in this?
Or the use of sand?

I’m getting frustrated every single year around this time when I want to start running trains again and the track is messed up so bad and I spend a month or two rebuilding.

Some sections that I never added sand to over the summer are just fine.

Should I secure the track in more places? Or let it all just float? I’ve had 1 summer of each method and neither one seems to work.

not sure it is related to sand or not. if the sand is working its way between the ladder/spline and causing humps then that may be a problem. i get up to two inches of frost heave every year that needs to be pushed down. i use recycled pvc for some of my spline, and it has degraded and broken in some areas. this spring i lifted the track in this section and removed the ballast under the spline and resettled the support posts. when all was said and done i cut approx 1/2 of rail out of one section to get everything to line up again. i do attach the track at closer intervals probably around 2-2-1/2 feet w/o issue. try chicken grit for ballast as one possible solution. though not economical, you might find something similar at a landscaping dealer by the five gallon bucket. get sharp cornered stone, not river rock. that will not work.


I can get some 1/4" minus easy as that’s what I used when I built my first layout on the ground. I might try that and see if it helps.

I’m wondering if it’s a combination of different things that I need to isolate.

By spline roadbed do you mean a ladder system?
For instance I use Cedar for my ladder; 5/16 by 1 inch sides with 3 x 4 x 1 inch blocks every 16 inches. the track with commercial plastic tie strips are fastened down every 3-4 foot. Everything is backfilled with 1/4 inch gravel for good drainage.

I have tried “crusher fines” for the fill in the past and found they did not allow the water to drain quickly and completely enough to work well.

Expansion and contraction will happen no matter what. If the track can’t go end to end or side to side it will go up, can’t be stopped but it can be slowed. Good gaps at joints, don’t fasten the screw/washer to tight let the track slip. Also expansion joint track sections are a big help on long straight runs. I do all of this and yet every spring there is 4-5 places that need to be taken out and relayed, it is just called maintenance.

Guess a ladder roadbed would be a more accurate description than a spline.

Most of this area that I’m having trouble with is in direct sunlight in the heat of the summer, but when I laid the track I gave expansion gaps ( and most of it was actually laid in the summer as well.

I’m going to have to take a deep look at this section and see what I can do. I know for sure last year I needed more 4x4 post supports and the benchwork was sagging in a couple areas.

I’m also thinking that the hand laid ties might be part of the issue as well. I get that annual maintenance is needed but dang I feel like this one section about 50 long is just kicking my butt.

It’s the expansion and contraction rate of the different materials. I would recommend not securing the ties to the ladder and just allow the track to float on top. I have no experience with hand spiked track outside but I’m guessing that the track wants to move in the ties that are screwed down and the spikes will not allow this. I used Aristo brass track but none of the ties are screwed to the track itself allowing the track to slide inside the ties (make sense)? I only have a couple screws securing the ties to the ladder (about 15’ apart) only to keep the squirrels from kicking it off the ladder on an elevated section. Everything else that is on the ground floats. The areas I get full sun are mainly on the curves and the curves will push outward with expansion and slightly slide off the ladder. If you feel you must secure the track to the ladder try using zip ties through a hole drilled into the PT spacers and leave them slightly loose allowing for some movement. You didn’t say what type of rail you were using but if it’s aluminum I believe you are going to have a lot more expansion/contraction than the brass or stainless.
Only my experience and perhaps it will help.

The first summer I didn’t secure the track at all and let it float. Had the same issues.

Yes I’m using aluminum rail.

I’m going to rethink this area and study what’s different. It might be something as simple as using a different style of rail joiners that aren’t allowing the rail to move at the ends.

Are you using rail clamps or slip joiners? I find that Slip joiners work better in full sun areas.
Is the problem area a long straight run? If so try adding some curvature to it.
I use several old LGB expansion sections with adapter clamps in the long sunny runs here.
The hold down screw/washer loose enough to let the track slide around?

You’ve probably already covered these things but just thought I’d mention them.

It’s not entirely a completely straight run but has a slight dog leg on it. I think the issue might be related to the retail joiners actually. In this section I used smaller rail joiners from Llagas Creek that don’t really have a lot of movement once the rail is in the joiners. The other sections have much more movement in the joiners themselves. I might try replacing those and seeing what happens.

The only place that I have really secured the track is one turnout. I pin nailed the ties to the spline and that section is holding quite well.

In the areas I tried the washer trick, it actually moved so much the track came off the washer ( this is due more to the fact of the individual ties vs a solid piece).

Worse case scenario I guess I can order some plastic ties from Llagas Creek for this area and replace the handlaid stuff with plastic ties and see if that makes a difference.

Craig, give this thread a read, it might give you something to work with.

Did some studying on the rail joiners in the problem section. They are all tight on the rail and don’t allow the rail to move around the joiners. The sections that have movement between the joiners have fewer issues and the track is in tack.

Split jaw has these .

So I think my issues might be a combination of things. In no particular order.

  1. Rail joiners that wouldn’t slide.
  2. Attachment to the spline that was too tight and didn’t allow the rail & ties to move
  3. Benchwork was unlevel (added more supports)
  4. Individual ties vs tie strips.

As much as I like the look of handlaid track, I might ( insert gasp here) be considering replacing the hand laid ties with commerical ties. I’m getting tired of every season having to go around the layout and adjust and move ties back into place. I might just try attaching the ties to a runner board and see what happens.