Roadbed with foam

[Anonymous]

Other posts have suggested that cork roadbed is noisier than foam roadbed which stands to reason as cork is denser. So, if you put track on plywood directly it would be the noisiest, track on cork on plywood the second noisiest, track on foam roadbed on plywood third, track on rigid foam the fourth and track on foam roadbed on rigid foam the least noise. I think I got that!...Walt

[Anonymous]

I'd heard that one of the advantages of using foam (e.g. rigid foam insulation) as roadbed was that it reduced noise considerably. I'm putting together a new layout and had planned to use a plywood subroadbed with foam roadbed for this reason. Now maybe I'll build a test section first.

Can anyone offer first-hand accounts of the sound qualities?

[Anonymous]

The principle reason I advocate the use of foam instead of plywood for sub roadbed is the ease of creating below grade level scenery(roads,rivers,ditches,ect..). I'm in N scale and have had layouts with plywood sub roadbed before I started using extruded styrofoam. I couldn't tell any difference in the amount of sound deadening between the two materials.
The greatest disadvantage to using foam any thicker than an inch is the difficulty created using under layout switch machines.

[Anonymous]

I was planning on using split cork on top of 1/2" plywood. Would you recommend i put foam inbetween the plywood and cork? Any benefit? Any disadvantages?

[Anonymous]

It is important to have a different type of material between the foam and track to deaden the sound. You can put track right on the foam, but the noise will be higher. You definetly want some kind of insulator material (roadbed, cork, anything) between the track and the foam on your main line.

[thirdrail1]

You don't need roadbed if you profile the ballast AND MOST IMPORTANTLY, the drainage ditches alongside the track, into the foam base. This profile can be built into a "hotwire" device. Most track is above the adjacent ground level, as track laid in the mud "pumps" and gets out of alignment and gauge.

[Anonymous]

Its up to you. You could glue roadbed to the foam and then glue track to the roadbed. Or like Jeff said, use roadbed for the mainline to elevate it above passing tracks and sidings which you can glue dirrectly to the foam.
In either case just be careful which glue you use as some will attack the foam. I've found carpenter's glue from Elmers to work very well.
Good luck.

[Javern]

i only used roadbed on my mainline, otherwise i just glued the track right to the foam board

[Anonymous]

Is roadbed needed if you are building your layout on foam board?