Layout construction/Sundeala/Top surface

[bike2steam]

The 25mm cover will deaden any sound,

 

Any thoughts or potential drawbacks to this solution?

 

Iain

 

Moving trains make noise, if the sound is excessive - slow down to scale speeds.

[WIMorrison]

I was considering subjects such as sustainability, longevity and strength which are created as a result of using this construction than a simplistic mandraulic resolution to a problem that is discussed regularly and at length across these forums.

[locomad]

What sort of 9mm ply do you find flexes more than Sundeala board? My experiences to date suggest that Sundeala has no structural integrity whatsoever whereas ply is reasonably rigid and very acceptable. I have even used 6mm ply to support gradients on a space frame layout and found that superior to Sundeala.

The next layout which will be 4m x 3m and which I am about to start once I have completed room insulation will be 9mm ply - Sundeala will not be anywhere near it and probably no cork either as you loose any benefits once you ballast the track.

Just my views, but I would like to know why you think ply isn’t rigid enough

I'am not an expert on plywood or sundeala for that matter, just that part of a batch of sundeala I purchased about 30 years ago seemed to be less flexible than a same size piece of 9 mm ply I acquired.

 

I used to buy sundeala 8' x 4' boards with a "K" quality stamp on from a proper builders merchant not the 4'x2' boards sold by some model shops it's a lot cheaper per square foot. I remember that when I was buying it the yard lads joking yet "another model railway in the making" it seemed the only customers who purchased it used it for layouts and not as an insulating board for which I believe it was originally intended for. I was also suggested that some retail outlets sold "fake" sundeala or some products closely related to it.

 

Aged sundeala has a certain smell about it, a smell one can't forget, I've come across someone who showed me his layout claiming it was sundeala on top, it certainly was not anything I used.

 

I've came across a built in room in a large warehouse where sundeala was used instead of plasterboard as internal wall, one could certainly smell it, it was used as a computer/office certainly very warm, the owner said it was great as he could pin paperwork anywhere!

 

It's used in schools a lot, in different colours again ability to take constantly pins in and out, I've read somewhere that quite a few local authorities are worried that pins placed in plasterboard which might contain asbestos have encouraged sundeala pin boards.

 

My last acquisition came from old pin boards, funny enough a "K" stamp was on the unpainted side

[DCB]

Moving trains make noise, if the sound is excessive - slow down to scale speeds.

Its the horrible grunting noises trains running on ballasted track makes on Sundela which is annoying.   I made the mistake of glueing ballast to a section of track on Sundela and didn't repeat the experiment.  However the sound of a train banging over a wide rail joint on a resonant surface is very satisfying especially at scale speed, not the 2mph beloved of some exhibition operators.

[Colin_McLeod]

I agree. Some people are obsessed with running trains too slow which is just as unrealistic as too fast.

[HerbertFrederick]

Reading all the contributions, for which I am grateful, I decided to buy some 1/2" ply in 8 x 4 sheets. In order to brace it correctly I screwed my 45 x 21 lengths into 90 x 21s which should give the plywood sufficient support. One question. Plywood should be braced properly. What spacings would members who have built their baseboards from this material recommend. The baseboards that I stripped down had spacings at 420 mm something between 16 and 17 inches. While expensive on timber I would have thought it strong enough.

[HerbertFrederick]

Just as an update. The baseboards are complete, apart from two very small sections and await the track. I used 4 x 1 PSE for the main frame supported on 2" x 2" legs. Then I covered this with 9mm plywood. Some modellers have been seen to glue 3mm cork on to the plywood and lay track on that. However, unlike sectional layouts such as those used on portable payouts eg 4' x 2' sections, a "one-piece" layout can provide a few extra problems.

Where there are right angled joins between one sheet of 9mm plywood and another there is the possibility of a small step, despite the fact that both sheets are mounted on the same underframe. I mentioned this to a fellow club member and we discussed the possibility of using a sander to smooth out the joins. I haven't tried this yet but it might be a solution. Another modeller said he'd used a covering of cork over the entire layout to ensure a smooth(er) surface and then laid the 3mm underlay for the track.

Having done the calculations I am going to need at least 21m of 1m wide cork sheet to do the layout. It is available in thicknesses of up to 5mm which should smooth out the imperfections. It would also make it relatively easy to pin things to it, if required.

Some use "Foamex" or foam board to fill in the gaps between the 3mm ply under the track. I have considered this too but it appears to have a rather smooth surfaced perhaps this might make it difficult to stick things to.

At this point I should add that I am hoping to use P4 as I have many boxes of OO gauge rolling stock and locomotives that my father bought.