Do I have to glue the cork underlay to plywood baseboard

[Bill Paddy Andy]

Hi Everyone 

Great to join the community! Currently well into the layout (thanks to lockdown!) have the track in position (tacked) with all cork(1.5) cut and in place! So I’m ready to drill slots for point motors! So to this beginner I don’t see the absolute reason to glue the cork to the ply. I’ll be pinning the track to the board then the ballast will be glued !! So I’d appreciate your experienced answers ! Thanks in advance! BPA ! 

[murphaph]

The "received wisdom" says don't tack (except to hold during gluing), glue. The reason behind that is noise transmission prevention. The more decoupled the track is from the baseboards, the less "rumble" you should have.

In fact some people have even moved on from cork to other materials to better insulate the track from the baseboards.

[Bill Paddy Andy]

18 minutes ago, murphaph said:

The "received wisdom" says don't tack (except to hold during gluing), glue. The reason behind that is noise transmission prevention. The more decoupled the track is from the baseboards, the less "rumble" you should have.

In fact some people have even moved on from cork to other materials to better insulate the track from the baseboards.

OK thanks ! when I say tack I mean I’ve temporarily put track in layout plan so I can decide where to drill slots for motors, I will be finally pinning the track to the board, and then ballasting, I’ll live with the sound fallout, but just wondering the benefit of glueing the cork to the ply! 

[irishthump]

Trouble is once you ballast the track it really doesn’t make much difference, it’s only marginally quieter.

[murrayec]

Dependant on the quality of the cork, it can expand and distort when using pva for doing the ballast if not stuck down! If your not worried about the sound I recommend sticking it down..

Eoin

[Galteemore]

Using copydex or latex glue is another alternative which allows a little more flex than straight PVA. It also allows you to peel everything off the board later rather than chipping at solidly dried PVA

Edited July 31, 2020 by Galteemore

[Noel]

Charlie of Chadwick model railway youtube fame dilutes copydex 4:1 with water and uses it to ballast track instead of pva. He swears there’s no transmission to baseboard guitar, unlike PVA. On a recent layout I’ve used double layers of 3mm closed cell dense foam with self adhesive backing.

Edited July 31, 2020 by Noel

[DiveController]

Personally agree with Noel and would use closed cell foam well wide of where your glued ballast will end, but you don't have to do anything, your railway.

I do remember photos of a beautiful railway model on this site a couple of years ago that had literally gone to pieces due to issues with the baseboards and underlays. If you're going to put the time into it I'd put it on the best foundation possible but up to you. 

[David Holman]

For me, using a cork base is more about forming the correct ballast shoulder as any sound proofing. Hence often do away with it on station and yard areas, where you would otherwise be covering the whole baseboard surface with cork. That said, 3mm cork floor tiles are great for this, being completely flat and thick enough to cut channels for wire in tube point rodding and the like.