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Track Ballast at module seams

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  • Member since
    July 2021
  • 173 posts
Track Ballast at module seams
Posted by NorthsideChi on Tuesday, June 28, 2022 10:04 AM

Currently restarting work on my elevated viaducts.  I use the Walthers urban viaducts and I'm creating modular segments that are 70" long so they can be stored on 6' shelves when not in use.

They are sturdy with plywood substrate and clad with the walthers kits.  Due to the weight, I have to fasten steel rods that run through the decks of the bridges to avoid bending and splitting when the modules are handled.

The ends have 3D printed cover plates that align and lock and electrically connect tracks, switch machines and lighting through barrel plug sockets (designed with the help of an electrical engineering friend).  As great as this is working so far in a prototype, I'm getting tripped up on the cosmetic appearance.  

What about the mysterious seam in the ballast along the tracks? Any tricks to diminish an obvious juncture?   I'd love to see some ideas.  Plus I need to protect the edge so it isn't getting abraded.  

Elsewhere I hide joints in logical spots, like behind blind spots of buildings, at the base of retaining walls or at the edge of curbs.  Was thinking of maybe creating wooden maintenance walkways that overlap the joints.  

  • Member since
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  • From: Milwaukee WI (Fox Point)
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Posted by dknelson on Tuesday, June 28, 2022 11:10 AM

A photo (or drawing) would help those of us who are more visually oriented.

A couple of preliminary thoughts.  How often will the modules actually be separated?  If not too often then seal the gap in some temporary way, and apply loose ballast on top?  If you don't want loose ballast because it can get into locomotive gears and drive trains, then loose ballast but rolled into long "strings" of Silly Putty to push into the gaps -- something you'd have to redo every time you separate and re-combine of course.

Another thought - not knowing just how wide these gaps are -- would be to ballast the top of a small and discrete T shape structural shape (wood or plastruct) that would be shoved into the gap.  Or in lieu of ballast, one of those stone textured spray paints?

I guess the steps of my thinking here are 1) what product (be it solid or soft) would by itself fill the gap and 2) how best to make the top of it match the ballast.  

Not related to your issue or problem, but for the tracks the bridge a gap on a portable layout, masking tape or duct tape on the bottom of the ties, and the sticky part between the ties could hold otherwise loose ballast.  That is kind of what I am thinking of here.

But again maybe a photo or drawing would show that I am mis comprehending the issue 

Dave Nelson


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  • From: Vancouver Island, BC
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Posted by selector on Tuesday, June 28, 2022 12:48 PM

If it is annoyingly obvious and detracts from the realistic view you'd rather have, I suggest the following:

Either wax paper of cling wrap, doubled, and held in the gap.  The idea is to keep it really thin, but it can't be so thin that removing the bridge is a grating, breaking, and risky chore because the gap is too close. I'll explain - You have two nearly abutting edges where the bridge can be lifted clear of the abutments. The gap is large enough that it will show, even with care ballasting the deck and the top of the abutment...correct? So, put something that can be easily removed and discarded in the gap and groom your ballast modestly tight to both sides of the removable barrier.  Glue well, make sure it's clean, shaped, and hard.  Then, lift out the bridge gently and remove the temporary dam/barrier, and when you reinstall the bridge you will hardly see the gap.

You can adjust the thickness of the gap to make it more effective, either making it hidden or making the clearance between the two ballast sections wider to ease bridge removal.

I have just used painters' masking tape for this purpose.

  • Member since
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  • From: US
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Posted by EMDSD40 on Tuesday, June 28, 2022 8:39 PM

Use wax paper to fill the gap as a "filler" and sprinkle some kitty litter. Cheap and easy to clean up. My entire HO and O gauge railroad is ballasted with kitty litter and never had a problem with it getting into gears or wheels. It is not glued down and been laying there 30+ years.

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  • From: Canada, eh?
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Posted by doctorwayne on Tuesday, June 28, 2022 10:15 PM

I'd consider gaps between modules to be quite acceptable, but if the lack of ballast at those gaps bothers you, simply clear-off some of the glued-in-place ballast on either side of the gaps, then lay down some carpet tape (sticky on both sides) coated with pressed-on ballast.  The tape should be good for a few uses, before you have to redo with fresh tape and ballast.
I'd suggest a uniform size for the cleared-away ballast and a matching size for the tape for all joints, so that you don't have to customise the tape size - one-size-fits-all saves work.


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Posted by "JaBear" on Wednesday, June 29, 2022 6:03 AM
Like Dave I’m struggling to visualise your situation.
I say this because at the risk of coming over as a “Smart Alec”, having gone through my photos mainly taken on either the Club or the “American Modular Group” modular layouts, both built to the same standards, I’m struggling to find photos that depict what I’m think you’re having difficulty with, though to be fair, I wasn’t specifically photographing module joints! The only real discrepancy is the actual changes in scenery.
The module ends including the rails are simple butt joints so the scenery / ballast goes to the very edge.
MJ by Bear, on Flickr
MJ1 by Bear, on Flickr
MJ2 by Bear, on Flickr
I also find that I’ve really only got one semi acceptable photo of modules in transportation mode.
Setting Up Ham 13 by Bear, on Flickr
Cheers, the Bear.Smile

"One difference between pessimists and optimists is that while pessimists are more often right, optimists have far more fun."

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Posted by rrebell on Wednesday, June 29, 2022 9:40 AM

There is a product out there called instant roadbed, heard you can still get it at autoparts stores under a different name. You could but a small strip down the seam and press the ballest into it. 

  • Member since
    July 2021
  • 173 posts
Posted by NorthsideChi on Friday, July 1, 2022 3:52 PM

Thanks everyone, and I was hoping for photos actually, so I welcome them greatly.  I'll post a few of my own when I'm back from vacation with my in-progress work, but I was certain people deal with this especially for layouts set up at shows.  I like the idea of a press-on tape or adhesive since I know I can't just keep re-gluing.

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    May 2008
  • From: Miles City, Montana
  • 2,082 posts
Posted by FRRYKid on Sunday, July 3, 2022 3:23 AM

I am a little late to this but I use something similar to what was mentioned. For the gaps on my sectional layout I use Duck tape similar to the color of my ballast on the joint track. (I also use it on my turnouts but that's a whole different reason.) Keeps the ballast contained and stuck down and doesn't stick to the section allowing for movement. (I have moved the layout once from my old apartment to my garage at my house.) 

"The only stupid question is the unasked question."
Brain waves can power an electric train. RealFact #832 from Snapple.

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