Noise Reduction. Where have I gone wrong

[Bino]

Woodland Scenics Roadbed is very good for noise reduction until fixed it to the boards. I have laid my track on plywood boards with the roadbed glued with Copydex. Code 75 track then glued to the roadbed again with Copydex.

 

The noise is worse than pinning the track directly to the boards.

 

Where have I gone wrong?

 

all advice gratefully received

 

Dave

[Ben Alder]

I laid a base layer of 5mm camping mat style foam on the boards an d then used Tracklay to ballast the track. This is an adhesive on one side foam and I don't glue it down - pin lightly to begin with until happy with running then run a bead of Copydex along it and sprinkle a scattering of ballast to hold in place. Points do have pins to stop the point motors shifting them, Result is smooth and almost silent running, but my are 3/4" block board which probably helps as well.

 

[brossard]

I laid my 0 gauge track on WS foam roadbed.  I used Tacky Glue to fix the foam to the board and the track to the foam.  Tacky Glue looks like PVA but dries rubbery.  The combination of foam and TG should, in theory, decouple the track from the board.  I have no experience with Copydex, it is unknown here.

 

My layout is a BLT so speeds aren't great.  I haven't noticed any excessive noise.

 

John

Edited December 7, 2021 by brossard

[Nearholmer]

Bino

 

i can’t say with certainty where you’ve gone wrong, if indeed you have, but it may be that the distances between supports below your baseboard surface are too great, allowing the plywood to act like a drum-skin, and the box-shape below the board as the drum-body.
 

If you want to resolve the problem, try gluing something to the underside of the plywood baseboard to stop it vibrating. In vehicles, the similar problem is often dealt with by putting dense foam/fibre on the back of the panel to act as a damper, but in our application fixing a piece of 2” x 1” timber along below the track will sometimes work - it is heavy in comparison with the trains, so their movement can’t transfer enough energy to move it about, and iit stiffens the druma-skin.

 

Kevin

[Bino]

16 hours ago, brossard said:

I laid my 0 gauge track on WS foam roadbed.  I used Tacky Glue to fix the foam to the board and the track to the foam.  Tacky Glue looks like PVA but dries rubbery.  The combination of foam and TG should, in theory, decouple the track from the board.  I have no experience with Copydex, it is unknown here.

 

My layout is a BLT so speeds aren't great.  I haven't noticed any excessive noise.

 

John

Thanks John. Copydex is also a rubber based adhesive,

[Bino]

12 hours ago, Nearholmer said:

Bino

 

i can’t say with certainty where you’ve gone wrong, if indeed you have, but it may be that the distances between supports below your baseboard surface are too great, allowing the plywood to act like a drum-skin, and the box-shape below the board as the drum-body.
 

If you want to resolve the problem, try gluing something to the underside of the plywood baseboard to stop it vibrating. In vehicles, the similar problem is often dealt with by putting dense foam/fibre on the back of the panel to act as a damper, but in our application fixing a piece of 2” x 1” timber along below the track will sometimes work - it is heavy in comparison with the trains, so their movement can’t transfer enough energy to move it about, and iit stiffens the druma-skin.

 

Kevin

Thanks Kevin, that makes sense. I'll try it out,

[RobinofLoxley]

Im a bit puzzled by this. The product you used looks like Neoprene foam, is it soft or is it rigid? I used a soft 6mm foam normally used for cushioning in printing processes (closed cell soft neoprene technically) and considered the result too quiet - and this was laid on quite a light plywood base, something that would have vibrated, but didnt. If the foam is rigid it will transmit some vibrations, so if you arent satisfied send the product back or you could try crushing the foam to soften it. Run a rolling pin up and down it and try it.

[Bino]

1 hour ago, RobinofLoxley said:

Im a bit puzzled by this. The product you used looks like Neoprene foam, is it soft or is it rigid? I used a soft 6mm foam normally used for cushioning in printing processes (closed cell soft neoprene technically) and considered the result too quiet - and this was laid on quite a light plywood base, something that would have vibrated, but didnt. If the foam is rigid it will transmit some vibrations, so if you arent satisfied send the product back or you could try crushing the foam to soften it. Run a rolling pin up and down it and try it.

the roadbed is soft foam. When glued to the boards and the track laid (not glued or pinned) the noise level is perfectly acceptable. However, once the track is glued down using Copydex the noise is pretty bad.