Bench-Roadbed

[marxalot]

I will be re-using a lot of open grid type benchwork on the new layout. This was made using 1x4's for the upper frame with 2x4's for legs. Most of the sections are 2'-6" by 8' in length with 4 legs. This type of bench worked well on the HO layout which had a lot of changing track elevations. Now on the new layout I'm pretty much thinking flat. With that said I will cover the top of the benchwork with plywood. Would 1/2" be acceptable? Another question I have relating to roadbed is this: Would it be acceptable to just use 1/4" cork road bed beneath the tracks on top of the plywood or should I add 1/2" homosote on top of the plywood? If adding the homosote I was considering just covering all the plywood, which might lead me back to the cork roadbed for some form of roadbed/ballast look for the track. More sound absorbing material is no doubt better so I'm wondering what experiences folks have had with less.

Thanks for your time.


Jim

[Dr. John]

If you truly want sound absorption, the key is to isolate the track from the plywood. This includes the screws that hold down track. Even with cork or homosote or foam, screws that reach the plywood will transmit sound.

Any of the materials you cite will work. The thicker, the better. Homosote and extruded foam will provide more sound insulation than cork, generally speaking. The combinaton of cork and homosote is not a bad idea, although I prefer foam since it is less susceptible to humidity. Homosote can swell or shrink depending on the level of moisture.

[daan]

If only using the isolation or cork for sound dampening, I would only do that under the trackwork. If you want to drill holes for lights, screw down accesoires and plant trees, I guess you'll be better of when the ground is srewable.
By using woodglue between the cork roadbed and the tracks, you won't need screws reaching through the cork sheet. It will however be troublesome to redesign your layout later on, since the woodglue hardenes up giving a strong bond.
Plastic ties can easily break when you want to get the tracks out again. A 0 guage mate from Holland used watersolvable woodglue to fasten his tracks. He changed his layout several times since, and all he has to do is soak the ballast with water and wait a few hours. The tracks can easily be peeled out then. In normal conditions the track stays solid and on it's place (after ballasting).

Another tip for soundreducement is to fill the hollow shells of locomotives with packing foam (not too much, motors need air to cool themselves) because the hollow shells amplify the sound of your motors & gears. It will however also reduce the sound if a soundsystem is installed.

[Anonymous]

I use 1/2" plywood, 1/2" construction foam and 5/16" split cork under GarGraves Flex track. I remove the track screws after glue-ballasting but with wooden ties sound transfer via screws is actually not a problem.

[fwright]

1/2 inch is plenty assuming reasonable support grid spacing. I use 16-18 inch spacing with 1/2 in plywood myself on a 4x8 table, and it's strong enough to hold my weight, and has never sagged.

Or, if you want much lighter weight at slightly higher cost, use 1.5 or 2 in thick extruded foam covered with 1/4 in plywood. I built a 3.5 ft x 5 ft table using this concept with no supports other than 1x3 around the perimeter around the foam (1.5 in thick). This also was plenty rigid with no sagging - supported a Christmas tree in the middle, being stepped on, stored against a wall, and mulitple transports while supported only on the wood edges. The 1/4in plywood on top, aside from adding rigidity, was put there to screw the track and accessories into.

Lots of good ideas here - use what you want and enjoy!

Fred Wright

[tschmidt]

I used a foam raodbed and it works very well. It is quieter than using cork. I have not used any ballast yet but when I do I can remove the few screws that hold the track in place can come out. The track will be even quieter then.

Tom

[marxalot]

Howdy! Thanks for the input; good ideas all. Let me cogitate on them and then make a decision........

Jim