Underlay, what's your poison ?

Discussion in 'Permanent Way' started by 3 LINK, 26 January 2015.

  1. 3 LINK

    3 LINK Western Thunderer

    Cork, closed cell foam or plonk it straight on the baseboard, I am at that time when I need to make a decision as to what if any underlay should be used.

    Being that my layout is a sleepy backwater, there will be no need for tons of steeply graded ballast shoulders, nor neatly laid ballast that looks like it's better suited up someone's driveway.

    There's the old school that prefer the cork roll and then the fairly recent choice of closed cell foam. I was quite interested in the foam until reading that supposedly it makes no difference at all regarding noise suppression. And after reading many topics on the subject of underlay I may not bother at all.

    I mean do we really want to quieten to noise? There's nothing wrong with the "clickerty-click in my opinion, it's just the mild roar of wheels rolling on metal that seem to offend most folk.

    My way of thinking at present is to lay the track straight onto the boards, and once the wiring is in place I want to try and fit some insulation foam to the bottom of the baseboards to try and stop the noise from reverberating out. I think the bottom of the baseboards are acting like a drum and up to 80% of the sound is exiting in that direction, but I maybe wrong :rolleyes: time will tell.

    Any thoughts on this subject ?

    Martyn.
     
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  2. JimG

    JimG Western Thunderer

    Martyn,

    The closed cell foam does allow your track to rise and fall under the weight of the stock, giving an element of suspension as the prototype track does.

    [EDIT] I meant to add that the use of PVA glue to stick sleepers down, and hold ballast, probably nullifies any noise limiting of whatever underlay you use. :)

    Jim.
     
    Last edited: 26 January 2015
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  3. steve1

    steve1 Western Thunderer

    Foam every time. I've used it on several layouts now and see no reason to change.

    steve
     
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  4. 3 LINK

    3 LINK Western Thunderer

    Hi Jim, Steve,

    That is the trouble with the PVA it does solidify everything to such an extent that surely the foam would become just as solid as laying the track straight onto the board.

    Some folk are now trying Copydex watered down the same way as with PVA , I have not tried this with ballast but it works OK for placing the track straight onto the boards, and it can be lifted if need be without damaging the track work.

    Martyn.
     
  5. SimonT

    SimonT Western Thunderer

    Martyn,
    another alternative is foam held down with carpet underlay spray glue. The Templot plan is then held down to the foam with the same glue. As an experiment, the big trainset used camping mat foam to give a bit more depth; there was no real gain. I am now using wooden floor underlay foam from B & Q. The one pack will do more track than I will ever build.

    Simon
     
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  6. jc2001

    jc2001 Western Thunderer

    I've used dilute Copydex to fix my ballast for some years now. It remains flexible and also doesn't seem to affect the colour of the ballast used. I bought a roll of foam intended to go under wooden floors many years ago. It is about 2mm thick (which is good) but a ghastly yellow (not so good).

    John
     
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  7. OzzyO

    OzzyO Western Thunderer

    Hello Martyn,

    I think that I'd go with 3mm thick cork floor tiles (try Wicks and compeer prices £9 for 9 1' square tiles) cut to shape then glue your track and ballast to that with PVA. They also have some acoustic foam that is 2mm thick on a roil.
    Glueing some foam insulation under the boards should help reduce the rumble.

    OzzyO.

    PS. it didn't take Steve long to get that point-work down.
     
    Last edited: 27 January 2015
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  8. OzzyO

    OzzyO Western Thunderer

  9. 3 LINK

    3 LINK Western Thunderer

    Thanks for the advice guys,

    I am tempted to try the closed cell foam option using the carpet underlay spray glue as Simon recommends, and if the diluted Copydex stays flexible enough maybe it might not transfer so much noise to the baseboards ?

    John, do you use a dash of washing up liquid to help saturate the diluted Copydex on the ballast ?

    Cheers,

    Martyn.
     
  10. Seahaven

    Seahaven Member

    Martyn

    Copydex with a hint of washing up liquid works fine for securing ballast.
    Remains flexible, which reduces noise transmission between different materials.
    This is the problem with PVA, as it forms a solid bond that transmits noise.
    Think of a loud speaker, there is a flexible link between the speaker and the box it is in.
    Another advantage of Copydex, if you change you design, you can lift the track relatively easily without causing major damage to the track.

    Yours

    Ian
     
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  11. 3 LINK

    3 LINK Western Thunderer

    Thanks Ian I will give it a try, I have used PVA in the past and have even fallen victim to the ballast turning a nice green tint :rolleyes:. So it's time to give the Copydex a go.

    Cheers,

    Martyn.
     
  12. JimG

    JimG Western Thunderer

    Martin,

    Another adhesive you can use for ballast which gives flexibility is diluted Artists' Matte Medium. It's usually obtainable from art stores and it might be a wee bit more expensive than Copydex, but it doesn't have the same smell when applying it - just in case you don't like the niff from Copydex. :)

    Sample prices on this page

    http://www.artsupplies.co.uk/item-liquitex-matt-medium.htm

    Jim.
     
    Last edited: 28 January 2015
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  13. SimonT

    SimonT Western Thunderer

    Nice tip, Jim. Try Hobby Craft, they do Galleria Matte Medium for £8 for 250ml. I've used gallons of the stuff in the paint on Hava Beer; I have to give this a try.

    Simon
     
  14. adrian

    adrian Flying Squad

    Thanks for that - is it latex based like Copydex? I used Copydex for sticking track and ballast down but I have to be really careful when I do that the domestic authorities are out. My better half has a severe allergic reaction to latex and Copydex is full of the stuff.
     
  15. JimG

    JimG Western Thunderer

    Last edited: 28 January 2015
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  16. Neil

    Neil Western Thunderer

    If it's any help I didn't use any underlay for Morfa, and it's one of my regrets that I didn't. In the past I always built shunting planks of a light railway/freight branch nature where the flatness of no underlay was a bit of an advantage. Morfa should have a shoulder and it's beginning to bug me that it doesn't. Morfa has solid chipboard tops which should help deaden the noise, but they don't. Perhaps it's because it sits on floorboards rather than carpet? The fiddle yard track which is lightly pinned down, rather than ballasted with pva, is pretty quiet. In some ways this isn't too bad as the noise of the train fades once it's off scene, but I also wish the noise was less on scene.

    I'm now contemplating a Belgian micro layout with trams and street running, goodness knows how I'll manage to get an acceptable noise level from track which will have to be solidly encased in roadway.
     
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  17. 3 LINK

    3 LINK Western Thunderer

    Thanks for the info Jim, although the smell is not a problem for me as I use to run a Fishery in France :D.

    Regards,

    Martyn.
     
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  18. steve1

    steve1 Western Thunderer

    Martyn,

    Although, I still use PVA to fix the tack to the foam, I've gone over to Johnson's Klear for ballast, ground cover etc. Everything seems to work fine.

    steve
     
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  19. John D

    John D Western Thunderer

    Bit late in the day.......have used the self-adhesive closed cell foam sheet used for sound proofing and found on e-bay. Provided that the baseboard surface is sealed with a coat of varnish it sticks down really well with no mess,
     
  20. 3 LINK

    3 LINK Western Thunderer

    Thanks for the info John,Steve.

    After reading one of the layout threads on here where a chap said not using any form of underlay was one of his biggest regrets, I have decided to use the closed cell foam and use the watered down Copydex method to secure the ballast in the hope that it will give the track bed that little bit of flexibility to deaden at least some of the noise.

    ATB,

    Martyn.