So, why DO we use cork?

[Ed Kapuscinski]

It's going to be cork and track time up in "the skook" soon and it got me thinking.

Why DO we use cork roadbed under track?

I get the aesthetic use of it to raise track above the surrounding grade, but there are many places where the track ISN'T above the surrounding grade.

I know there's a bit of a sound deadening aspect to it too, but does it provide that pronounced of an effect to be worth it?

[chuck geiger]

My last little guy 2x4, first time ever didn't use it and no problem:

[wvgca]

well, it DOES have some sound reducing qualities , unfortunately most of it is reduced through 1] nails 2]rigid ballast glue [like white glue] ..  leaving not much, lol

[DKS]

I'll admit to being prejudiced against cork, mostly for the fact that we've used it since dirt was invented, and there seem to be too many "sheep" out there who don't question the norm. I'll confess I have used it recently, but only on "retro" layouts as part of the whole "retro" vibe.

Pros:

* Creates a roadbed profile, at least for mainlines--as you noted, on occasion that's not needed (in which case you can just bury it in ballast and scenery junk).

* It may provide some sound deadening, although when I've used it, I haven't detected a substantial noise reduction. When it's applied to foam, there's no detectable difference.

Cons:

* An added expense that isn't required, considering there are other ways to achieve the same result.

* An added construction step that isn't required; see above.

Myself, I still prefer double-sided foam tape. It instantly bonds the track to virtually any layout surface, and it can be shaped to create a roadbed profile as needed. However, it is an added cost, and it's not revision-friendly; you'd better be happy with how the track is laid the first time, because a second time can come at an unexpected cost.

If I were to make a recommendation that doesn't include something like double-sided foam tape, I'd say carve the foam (assuming foam is your tracklaying surface) to create a roadbed profile (hot wire, packing knife, rasp, etc.), and just lay the track right on the foam: glue it down with Elmer's glue, Tacky, LocTite PowerGrab, or any number of other foam-friendly adhesives; hold the track in place with small straight pins until the glue sets, then pull them.

Some modelers complain that the foam amplifies noise, but that's only true until you add scenery; then it turns dead quiet.

There will be a dozen or more replies with countless other suggestions, so I'm just part of the noise--it's up to you to decide what makes the most sense for you.

[Dave V]

On the RGS I used it simply for the elevated grade effect.  Even 65 years after the track was pulled there's still evidence of a raised roadbed in may places along the old RGS.  But, since 1) the RGS also had some pretty piss-poor grading in spots and 2) it was narrow gauge, I used N scale cork.

I do believe the choice of cork as a material comes from the fact that that's what was readily available and cheap back in the old days.  More advanced materials like the foam used in Woodland Scenics Trackbed (which BTW is entirely too "squishy" for the job as I learned the hard way) were not available.  And when you laid track down onto Homasote laminated onto plywood, you'd get a sound deadening effect.

So, in effect, I believe it's one of those "that's the way we've always done it" kinda things even if it's a whole lot less necessary in the age of foam.

[spookshow]

I'm not a "we", I use Unitrack 

-Mark

[C855B]

... does it provide that pronounced of an effect to be worth it?

In my observation, yes, especially on XPS. When first considering this I measured as much as a 10 dBA difference (IIRC) on a test loop.

well, it DOES have some sound reducing qualities , unfortunately most of it is reduced through 1] nails 2]rigid ballast glue [like white glue] ..  leaving not much, lol

Nails? I haven't used nails to hold down N scale track since... uh... 1968, on my first layout. But I agree ballasting may defeat some of the sound suppression benefits. I was warned about this early in my current construction after running sound tests and decided it was a live-with. There may be - but I don't know, haven't further tested - a perceptible difference between a "hard" adhesive like white glue and something slightly more resilient like the acrylic matte medium I use to affix the ballast. My spidey sense portends another experiment in the near future.

On the RGS I used it simply for the elevated grade effect. ...

Truthfully, that's sort of my motivation, too. Instant profile. To that end, I've been using strips of 1/16" bulletin board cork for "lesser", lower-profile running track, and then nothing at all for industrial spurs and setout tracks where ballast stone would typically be less than visible. I haven't built any big yards yet, so the debate will be 1/16" cork versus nothing for yard tracks. Picture I have in front of me of yard trackage from the 1:1 RR and era I'm targeting is hinting that nuthin' might just be the best representation.

[Chris333]

I used it because it's easy to sand to help level the foam. I did a bunch of work to the foam first, but it still wasn't level. I first drew the track center lines on the foam then took a 24" flexible ruler to find all the high and low spots. Sanded some down and fill others. Put the cork on top of that and leveled it as well. I hate watching steam locos dip up and down.

In this photo you can see me using spackle and black masking tape to build up dips in the foam. You can't see the areas the were sanded down.
https://photos.app.goo.gl/9WUiNXhCVtPuuwe9A
Long ruler used to find the dips:
https://photos.app.goo.gl/tH5JGPJ2iuvm6MV16

Side note that I now flood ACC to secure track because ain't nobody got time for that caulk to cure. Can't ACC foam.

Another side note. I borrowed a 6' level from work for the layout because you'd be surprised how much more accurate it is from a 2' level used in 3 different spots.

I've done track right on the foam as well, but cork is pretty cheap and easy. Heck for your beat up Conrail coal track you might be better off wacking the foam with a hammer first 

[Ed Kapuscinski]

I used it because it's easy to sand to help level the foam. I did a bunch of work to the foam first, but it still wasn't level. I first drew the track center lines on the foam then took a 24" flexible ruler to find all the high and low spots. Sanded some down and fill others. Put the cork on top of that and leveled it as well. I hate watching steam locos dip up and down.

In this photo you can see me using spackle and black masking tape to build up dips in the foam. You can't see the areas the were sanded down.
https://photos.app.goo.gl/9WUiNXhCVtPuuwe9A
Long ruler used to find the dips:
https://photos.app.goo.gl/tH5JGPJ2iuvm6MV16

Side note that I now flood ACC to secure track because ain't nobody got time for that caulk to cure. Can't ACC foam.

Another side note. I borrowed a 6' level from work for the layout because you'd be surprised how much more accurate it is from a 2' level used in 3 different spots.

I've done track right on the foam as well, but cork is pretty cheap and easy. Heck for your beat up Conrail coal track you might be better off wacking the foam with a hammer first 

And... you just convinced me to stick with it, if for no other reason than the ability to use it to level everything out.

THANK YOU.

Also, I plan on using single strips so I can build up my OWN profiles. I hate the way it sticks out too far.

[MichaelWinicki]

I have places on my layout where the track is laid directly on 1" extruded Styrofoam base and other places (well most places) where the track is laid on Woodland Scenics roadbed and there is far more extraneous noise coming from trains running on non-roadbed supported trackage.

Cork or WS roadbed– either is better for at least mainline trackage than doing the track on Styrofoam thing.

[Point353]

It's going to be cork and track time up in "the skook" soon and it got me thinking.
Why DO we use cork roadbed under track?
I get the aesthetic use of it to raise track above the surrounding grade, but there are many places where the track ISN'T above the surrounding grade.
I know there's a bit of a sound deadening aspect to it too, but does it provide that pronounced of an effect to be worth it?

In the good old days, when subroadbed/framework/tabletop was usually wood, it was much easier to drive the track holding nails into cork.
Roadbed made from homasote was another option and is still available ready-made: https://cascaderailsupply.com/collections/n-scale-30-degree-roadbed
Another alternative to cork, of which you're probably aware, is the Track-Bed roadbed product from Woodland Scenics: https://woodlandscenics.woodlandscenics.com/show/category/NScaleTrackBedSystem
Now that foam board insulation has come into being as a layout base, along with various adhesives to attach the track, ease of use with track nails can be a nonfactor.
Also, if you're modeling a less than well maintained line, using some sort of roadbed to establish the ballast profile may be unnecessary, if not a disadvantage.   

[mplsjct]

I don’t use it, most of layout represents city trackage, where the elevated look isn’t necessary.

[Missaberoad]

Because cork roadbed smells like my childhood. 

Besides the nostalgia factor @Chris333 points pretty much cover my thoughts on the subject...

Of course my current layout is unitrack on plywood, but it's far from ideal   

[wazzou]

I have places on my layout where the track is laid directly on 1" extruded Styrofoam base and other places (well most places) where the track is laid on Woodland Scenics roadbed and there is far more extraneous noise coming from trains running on non-roadbed supported trackage.

Cork or WS roadbed– either is better for at least mainline trackage than doing the track on Styrofoam thing.

+1
In my experience, track placed directly on foam is like a tuning fork.
IMO, it's much louder than when on cork.
When I modeled heavy mainline trackage, I'd actually use HO cork with N Scale cork glued on it.
If you look at prototype drawings of track profiles, this method pretty much mimicked it.

[wazzou]

Does anyone that was in HO Scale remember the Cal Scale wood track bed?