So, why DO we use cork?

[C855B]

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

Yes. With and without ties.

The Cal Scale turnout kits were a trip. The pivoting points system resembled what we call "high speed" turnouts, with both points and frog closures. I can't confirm that the movable frog really helped anything because both the clubs I was in had the bad habit of spiking switches closed. Nobody wanted to fix switch machines, or the unreliable modified toggles that controlled them, they just wanted running loops to play on for the monthly "meeting".

[Iain]

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.

To be fair, in a lot of places on the old NS, the dipping and bobbing steam engine would be prototypical!

[mmagliaro]

I used it when I started in N Scale in the 1980s because "that's what roadbed was", at least according to 99% of what you'd see in the train stores and the magazines.  I remember thinking how "cool" I was because I wasn't nailing brass rail sectional snap track down to plywood (painted green, of course!), like I did in my childhood HO days.

But on my current layout, I used nothing.  I glued the track directly to the foam top, and I agree, unless you are ballasting a mainline or other trackage that is supposed to have a pronounced profile above the surrounding terrain, I think it looks better without.

As for noise... meh.   I don't think it's particularly loud or quiet either way.

[CHUCKGEO]

Those UNITRACK (KATO and BACHMANN) to my thinking look toy-like. First thing that grabs my attention when I see a layout made of this stuff is the gray snake on a table. Even painted or weathered it continues to be a focal point. I truly believe it ruins the look, and is a Deep State plot to bring back LIONEL third rail in 1/48th scale. I've used cork and different materials when available. Nothing wrong with Old School.  If while running your trains, and you find that the wife makes a comment that the noise is deafening, tell her to "make you a sandwich". You're wearing long pants, so be a man.   

[SandyEggoJake]

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.

This. 

Plus, with ACC, you can cleanly remove track from the roadbed with debonder should you wish to reposition.   Sure ACC may be more brittle than glue or caulk.  But with ballast glued down, I've yet had issues. 
At least that's what I told myself when I adopted ACC to affix track and ripped out all my crappy Woodland scenic foam bed and went back to cork.  Cork can also be sanded and even soldered on with far less issues.   

[milw156]

As for noise... meh.   I don't think it's particularly loud or quiet either way.

Simply adjusting CV 65 (upwards) can make this a non issue! 

[prr7161]

I used it because it's easy to sand to help level the foam.

Also for Homasote, which is not terribly smooth either.  I'm feathering the cork down from the mainline for yards and sidings to go direct onto the Homasote, and a little vertical movement on those tracks is OK.  But much less so for main lines.

Plus, I recently bought a box of cork (75 feet total) from Klein's for under $20.  That works out to less than a quarter per foot, which is pretty negligible cost relative to track.

[ednadolski]

Why DO we use cork roadbed under track?

Because MR says so...?   

(The Other) Ed

[robert3985]

I use Midwest Cork Products N-scale and HO-scale cork to lay my Rail-Craft C55 and hand-laid C40 track on except in large yards, industries and urban areas...where I use sheet cork bought at the local The Home Depot or Lowes.

The vast majority of my subroadbed is laminated splined Masonite, which is very dense when glued with yellow carpenter's glue and clamped.  I do it in maximum 6' long sections, which is the maximum length of my layout sections, taking the dried spline subroadbed assembly to the local cabinetry shop and having the top side planed.

After the subroadbed is secured exactly where it should be on my twin L-girder benchwork using premium pine 1x2's as risers, it's time to glue on the cork roadbed after I draw the track centerlines on the tops of the splined subroadbed.  I use T-pins then slabs of 3/4" plywood that's scrap weighted with books to hold the cork roadbed flat until the yellow carpenter's glue dries.

After the glue has cured, I take an 8" long sanding block with 220 grit paper on it, and sand the top surface of the cork flat.  On mainline curves, sometimes I'll sand in the superelevation, using an inclinometer to check the angle.

After I've sanded and vacuumed all of my cork roadbed, I then lay my Rail-Craft flex (or Micro Engineering flex in areas that can't be closely photographed) using the seam between the two pieces of cork roadbed as a reference line to run down the center of the ties.

I glue my track down with watery CA and Accelerator...mmmmm....love that smell!!

After the track is in I cut through the cork about 1/16" from the end of the ties and remove the slope completely, and sand an angle into the cork's edge, breaking the sharp angle just outside the ties.

When I ballast, I use my own custom mix of graded and de-dusted Highball N-scale ballast and natural dirt, and I get the correct ballast profile using a Styrene profiler I've made that registers on the railheads that scoops the ballast into the correct ballast profile, then I glue it down using traditional methods with diluted Elmer's Glue-All and a few drops of Dawn dish soap as a wetting agent after wetting it down nicely with a small atomizer loaded with slightly soapy water.

The cork/ballast/splined Masonite combination is the quietest (by far) of any model trackwork I've ever heard, and exponentially more quiet than track laid on thick extruded Polystyrene sheets which I tested on two 6' modules several years ago.

I like the cork's flexibility, being able to be readily sanded and leveled up, and sanded for transition to lower industrial or siding/spur trackage.  Sanding in superelevation is easy too with a good inclinometer to get consistency in the angle I'm sanding.

I don't recommend using a flexible roadbed, such as Woodland Scenic's, or foam tape, neither of which can be sanded...which is essential IMO for smooth trackwork...maybe not for ultra-small layouts, but for large scenes like I create, smooth mainline trackage makes the trains look and run much better than a bumpy roadbed.

Cheerio!
Bob Gilmore

[nuno81291]

Easy to work with. I use wood glue to glue it to my base of ply. Use white glue and pins/weights where appropriate for track to it. Easy to make turns, sand to transition to flat or non mainline elevated trackage. I used the WS foam before, as well as cut strips of craft foam sheet in certain areas. That stuff is fine too but I find the cork and wood glue make a very solid base. A bit of isopropyl and you can remove it if need be like my recent rework of a branch on my layout.

[OldEastRR]

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

What is your subgrade made of?

[OldEastRR]

First I nailed track (lionel 3-rail) directly to sheet plywood. Then I tried doing it in N when I changed scales. Much smashed rails, shattered ties. Saw in an Atlas how-to book that cork was a good way to go. So then came cork on plywood -- nails went through cork ok but really resisted the plywood. So then I went with cork on homasote (maybe because the EMRRC used it and I'd just joined) rested on the cross members on L-girders. Without a supporting plywood sheet. And the parts between the supports sagged. And I wasn't trying to model the PC!!
So I went to cork on homasote on plywood cookie-cuttered and supported by risers on L-girders. It worked fine, it wasn't noisy (I remembered the vibration noise when my Lionel ran on bare plywood), so I just stayed with that.
This last layout I cookie-cuttered all the homasote (even on flat areas) so only the track ROW was on cork/homasote. Left the tabletop  plywood base in towns and industrial areas and used extruded foam to fill in the land areas that weren't tracked. So I can easily model high and low spots even between parallel track, install waterways where I want them, and break up the look that the track, scenery and town are all on a common flat plane (plain).
HOWEVER .... my advice is to stick with the techniques you've used the most that gave you the best satisfaction. Especially if you're experienced at getting the results you want. I never got interested in track on bare foam then carved away contours, or the splined roadbed, or other methods that have come down the pike since I settled on my best way. You can make cork look unballasted without shoulders, uneven, partially washed-away subbed, ties hanging unsupported in the air, or any of the other various kinds of badly-degraded PC trackage you want to model.
About homasote: it's not easy to find, at least around me. Extruded foam has pretty much crowded out homasote as the go-to insulation in construction. Not so good insulation against sound, tho.

[wm3798]

Because cork roadbed smells like my childhood. 

This.  A thousand times this!

[DKS]

I don't recommend using a flexible roadbed, such as Woodland Scenic's, or foam tape, neither of which can be sanded...which is essential IMO for smooth trackwork...

You can sand extruded styrene foam; thus you can create a nice smooth subroadbed prior to applying foam tape. (Ask me how I know this.)

Plus, with ACC, you can cleanly remove track from the roadbed with debonder should you wish to reposition.   Sure ACC may be more brittle than glue or caulk.  But with ballast glued down, I've yet had issues.

For Unitrack or other roadbed track, I use CA exclusively now to bond it to wood, Foamcore and other surfaces with excellent results.

 

[davefoxx]

Because my railroad needs the track raised on roadbed, I like cork roadbed.  It's easy, it's readily available, and it's inexpensive.  Why mess with that?  Oh, and @Missaberoad's reference to olfactory memory, too.

DFF