Track construction.

[Philip Hall]

I would also advocate a flexible underlay. I shall go for rubber/Evostik/Copydex on my new layout, the theory being I shall get a degree of springing in the track, which will help no end with converted, rigid proprietary locos and stock, not to mention sound insulation. I saw this very effectively on the late Ken Northwood's 'North Devonshire', where the track was actually fixed to a paper substrate which 'floated' on the rubber underlay. Running was very quiet, the only drawback being that some of Ken's heavier locos (mind you, they were all pretty heavy) like the King, whitemetal with a boiler full of lead, about 2lb I think, visually depressed the track as it went over! But nothing ever came off...

Philip

[jim s-w]

Give me rigid track any day. With functional chairs the only track movement you get is fully controlled. With soft track the track will move in any direction it chooses.

Cheers

Jim

[Philip Hall]

I'm not thinking the track will move around much, hardly at all, more a bit of resilience which you don't get when it's glued down hard with PVA. I used Copydex with great success on the last layout, firstly on cork, then on an extension I used rubber (actually some kind of draught excluder) and it worked fine. After all, prototype track is not held down rigidly, it just rests in the ballast and weight does the rest. Of course we can't do that, we need some form of fixing.

Actually, I don't think Copydex is that ideal, as it can be difficult to drill through as has been said on this forum. But it does stick quite well - I even had a baseboard joint through the middle of a turnout and all that held it down was the latex.

Philip

[John Bateson]

Philip,
Would a camping mat be a good base?
John

[grovenor-2685]

Would a camping mat be a good base?

Iain Rice espoused them at length in his track builders guides.
Keith

[Philip Hall]

I think that a camping mat might be a bit thick. It's got to be absolutely flat of course, so I like the underlay that Norman Solomon uses. I also intend to have everything, wiring, point controls etc. on the surface, in channels cut in either the board or the underlay. This is because with the layout probably having to be on shelves above my workbenches in the loft, I need every inch of under board space, allied to not wanting to bend down to do things.

Philip

[John Bateson]

Philip,
Forgiev the obvious and maybe slightly daft question - but what does Norman Solomon use?
John

[craig_whilding]

Exactoscale do/did sell foam underlay of much higher quality and density than that in a camping mat and seems to work well if you want something cushioned.

Probably just as worthwhile to sort out the 'drum' effect of the underside of most baseboards though!

[martin goodall]

Exactoscale do/did sell foam underlay of much higher quality and density than that in a camping mat and seems to work well if you want something cushioned.

Probably just as worthwhile to sort out the 'drum' effect of the underside of most baseboards though!

The track on my Burford layout is laid on this material. I believe the trade name of the material was 'Plastizote'. I cannot say that this underlay is any quieter than cork.

I have never used camping mat, but it is a thicker material and so I would expect it to be a more effective sound insulator.

[doggeface]

Probably just as worthwhile to sort out the 'drum' effect of the underside of most baseboards though![/quote]


In OO scale I have used a wide variety of surface materials. All have similar noise levels but are slightly better than bare boards. Most of the noise is clearly radiated directly from the rails and does not appear to have the expected nodes which vibrating materials usually reacts to when mechanically shorted.

Whilst I am posting ---- what are the different applications for "thick" and "thin" sleepers?

[Chris Mitton]

Running was very quiet, the only drawback being that some of Ken's heavier locos (mind you, they were all pretty heavy) like the King, whitemetal with a boiler full of lead, about 2lb I think, visually depressed the track as it went over! But nothing ever came off...

Philip

Why is that a drawback? I vividly remember many years ago watching a Class 40 trundling slowly through the yard next to the NRM car park in York, and being surprised to see the rail joints deflecting vertically, and returning to their normal line, by a good three inches for every axle that passed over. Mind you, they were pretty heavy beasts as well.....wonder where they put the lead?

I agree with Philip, our track, like the real thing, needs to be resilient in the vertical plane - surely the springing of the vehicles and the springiness of the trackbed should complement and dampen each other? Likewise it needs to be moveable in the longitudinal direction, for the same reason as the prototype (expansion). The only direction in which it needs to be firmly anchored is the transverse, as that produces the forces that keep the trains on the rails (or not!) in anything except a straight line.

Regards
Chris

[Will L]

I agree with Philip, our track, like the real thing, needs to be resilient in the vertical plane

I'm not at all sure that the physics scales, i.e. our rails are much more rigid in relationship to out loco's weight, than is real rail under real loco's. If so, the rail distorting under the loco just isn't going to happen in the way it does on the prototype. So foam underlays may help deaden noise, if that bothers you, but I doubt it contributes much to good running.

Will

[Philip Hall]

but what does Norman Solomon use?

I'd have to look back at his MRJ articles to find out exactly, but I think it's like the Exactoscale stuff. C&L sell it as well - it looks the same to me - but Norman got in much larger quantities as he uses so much of it. I wasn't going to look up the article for the source until I started building the layout...

Philip

[Terry Bendall]

Would a camping mat be a good base?

The Mid Sussex group have used 10mm camping mat on Brighton Road. It has worked but there have been quite a lot of difficulties at baseboard joints where it in some cases it has been necessary to put pins through the mat into the baseboard. Barry Luck's view - and he has done much of the work on the layout, is that he would not use it again.

Terry Bendall

[Trevor Grout]

Would a camping mat be a good base?

The Mid Sussex group have used 10mm camping mat on Brighton Road. It has worked but there have been quite a lot of difficulties at baseboard joints where it in some cases it has been necessary to put pins through the mat into the baseboard. Barry Luck's view - and he has done much of the work on the layout, is that he would not use it again.

Terry Bendall

Terry,

Would that be the glue joint from mat to baseboard that failed, I understand that closed cell foam has a tendency to do this as the glue has nothing to grip on the mat.

regards
trevor

[jim s-w]

I agree with Philip, our track, like the real thing, needs to be resilient in the vertical plane

I'm not at all sure that the physics scales, i.e. our rails are much more rigid in relationship to out loco's weight, than is real rail under real loco's. If so, the rail distorting under the loco just isn't going to happen in the way it does on the prototype. So foam underlays may help deaden noise, if that bothers you, but I doubt it contributes much to good running.

Will

I agree Will

Assume for a moment that soft underlays do allow the track to move (which I don't think it does) no one has ever convinced me that such movement is in any way controlled. As far as I can tell such movement can be up/down left or right with nothing but hope that it will be in the direction the builder wants.

Or to look at it another way. If the real railway could get it's track dead smooth, and solid thus meaning suspension wasn't needed and the ride was perfect would they? Are we engineering in a solution to a problem we don't actually have?

Cheers

Jim

[martin goodall]

Would a camping mat be a good base?

The Mid Sussex group have used 10mm camping mat on Brighton Road. It has worked but there have been quite a lot of difficulties at baseboard joints where it in some cases it has been necessary to put pins through the mat into the baseboard. Barry Luck's view - and he has done much of the work on the layout, is that he would not use it again.

Terry Bendall

Using the Exactoscale 'Plastizote' material mentioned earlier, I took the precaution of laying obechi strips of the same thickness at basebaord joints. I think you would need to do the same (with a thicker section of wood) if using camping mat.

[Armchair Modeller]

Do the trains make significantly more noise at baseboard joints, when they run over the obechi strips, than they do anywhere else on your layout?

[doggeface]

I have used 5mm soft(ish) soundproofing as a surface material and it is very happy to accept pins or adhesive fixings except where the transitions to lifting hinged sections occur. I found it necessary to fix 5mm ply strips at the edges with the translation filled with wood filler and sanded to ensure a common line across the gap. until I had done this the cut track migrated at will ( not that a 300 year old wood and stone structure is any too stable! I can clearly hear the progress across these sections.

The failure to retain it's configuration is so irritating that the current P4 system will eliminate these access points and revert to a point to point system (the WSR is a good GW prototype) which can justify early DE's on excursions etc!

I can just squeeze curves of 1M20 in (4.5ch) so hopefully sprung buffers and hook fasteners will be functional.

I am finding it very difficult to just tear up my present system and seek ways of lifting OO and laying 1883 but then I wait very impatiently for the wherewithal to start work. Meanwhile ebay continues to sell off the stock which is excessive or non convertable.

Regards

Peter

[martin goodall]

Do the trains make significantly more noise at baseboard joints, when they run over the obechi strips, than they do anywhere else on your layout?

No, not at all. The baseboard frame is immediately underneath, so you do not have the 'sounding board' which you might have away from the edge of the baseboard.

I should have mentioned that I would recommend the use of obechi strips (about 1/2-inch wide) at baseboard joints even when using cork underlay. This was done on both 'Heckmondwike' and 'Bodmin', and entirely obviated any problems with the track underlay at baseboard joints. (That is where I got the idea.)

[Terry Bendall]

Would that be the glue joint from mat to baseboard that failed, I understand that closed cell foam has a tendency to do this as the glue has nothing to grip on the mat.

Trevor

I will have to check with Barry on this but I think the main problem is in keeping alignment of tracks across baseboard joints vertically and horizontally, and there are a lot of these on the layout. (See the pictures from the Scaleforum 2010 Retrospective) From memory the foam stayed stuck to the baseboard surface but there was a tendency for some of the wooden sleepers to lift. I think that the use of wooden strips at joints, as others have suggested, would solve the problem. Brighton Road was started 12 years ago and techniques have developed since then. Some of us of course remain firmly rooted in the past, both in techniques employed and in the period modelled. (Apart from when I am modelling the D&E period)

Terry Bendall

[Rod Cameron]

On Eridge we are using the Exactoscale foam, but at the board joins this is terminated short of the joint and replaced with some fairly hefty copperclad, screws, brass bar and solder, as hopefully the picture shows:

080626 012.jpg

[Armchair Modeller]

Do the trains make significantly more noise at baseboard joints, when they run over the obechi strips, than they do anywhere else on your layout?

No, not at all. The baseboard frame is immediately underneath, so you do not have the 'sounding board' which you might have away from the edge of the baseboard.

I should have mentioned that I would recommend the use of obechi strips (about 1/2-inch wide) at baseboard joints even when using cork underlay. This was done on both 'Heckmondwike' and 'Bodmin', and entirely obviated any problems with the track underlay at baseboard joints. (That is where I got the idea.)

Sorry to be so inquisitive, but what material and thickness are you using for the baseboard top, please?

[martin goodall]

Sorry to be so inquisitive, but what material and thickness are you using for the baseboard top, please?

In the case of Burford, half-inch chipboard - very solid and very heavy, but this does not form a 'sounding board' so is a good choice from that point of view. But I think I might use ply for an exhibition layout if I were to build another one in the future.