Gaps between Sundeala panels

[rhobat bryn]

I have a baseboard kept in the garage but over time a gap has opened up between the sundeala panels, presumably due to shrinkage.  Can anyone suggest a good way of filling in these gaps without disturbing the eveness of the surface?

[Graeme Dunbar]

I think it very much depends on the circumstances. Are these bare boards or do they have a layout on them? What is the construction method?

If the Sundeala is suspended over cross-members I'd check carefully to see it has sagged as well as shrunk, I'd be far more worried about the sagging as bridging a gap of a few mm is insignificant, but a series of humps and dips in the surface could spell a lot of trouble. If the Sundeala is laid on a solid surface then gaps are quite probably just a cosmetic problem.

[rhobat bryn]

Currently, there is only track laid on them as the layout is still developing.  Having checked the baseboard, there are no humps or dips as you suggested as the framework on which the Sundeala is mounted is closely fitted, presumably to avoid the problem you mention.  Given that's the case, what would you recommend as the best way of filling the gaps?

[Darren Hedges]

How wide are the gaps?

Darren.

[Graeme Dunbar]

How big are the gaps?

The best answer I have is that unless it is imperative to fill the gaps then don't - disguise or cover them.

Reasons not to fill gaps: if a wet and sloppy filler is used and a large amount of it is required it may well soak into the edge of the Sundeala and possibly make it swell up. If a rigid filler is used and the conditions are so severe that they cause the gaps to close up again, it may put the surface under stress and then leave a gap when shrinkage occurs once more. (Done that - forgot to tape the joints on plasterboard in a bathroom.)

In many places, the gaps may well be covered by scenery. One reason for filling the gaps might be to prevent small objects disappearing down them in say a fiddle yard. I'm in favour of using 3 mm cork underlay under track or the black foam equivalent so that will cover gaps. Some people paste a full-sized track plan down and lay track directly on top of that. I hesitate to suggest pasting a covering over the whole surface just in case the paste causes the surface to swell, but lining paper is good stuff (and a good source of inexpensive paper for drawing full-size track plans). If you are concerned about slopping watery glue about over the whole surface then Spraymount would do it. A really benign gap filler is Plasticine. It is flexible and used for "planting" removable buildings to hide the ugly gap where they sit on the ground.

However, people make scenery out of rigid plaster successfully, though I remember the first layout I built at the age of about 13 where the papier mache hill shrank and warped the side panel, so you pays your money and makes your choice! I think it is hard to give a definitive answer as it is impossible to predict all the conditions that may be met. There are stories of very well built layouts suffering on the way to an exhibition due to being stuck in a traffic jam in hot sun.

[pilotfriend]

Frankly, Sundeala is in my opinion a completely useless material which should have left the model railway scene about forty years ago. IMO, baseboards should be constructed in plywood.

[B.Meldon]

I agree with John on this, Sundeala and other

[Graeme Dunbar]

I'm not a fan of Sundeala either, but many people use it. If everybody suffered the horror stories told of it then I'm sure it would have disappeared years ago. My main objection is its weight and is a very poor structural material. However I can see its attractions for use as a base in fiddleyards where there could be a desire to pin track down rather than glue and ballast it.

Working with what Bryn (I assume you are Bryn?) has got, if the baseboard is moving to a relatively stable permanent environment then I would not worry. However if it is moving to a railway room in the attic that is cold and damp in the winter and baking hot in the summer I might think twice before building anything permanent on it. If it is moving from lengthy storage in a garage to a bedroom or similar location I'd definitely let it acclimatize for  a few weeks.

[rhobat bryn]

The gaps are 1mm, 2mm and 1mm respectively.  The idea of using Plasticine is an appealing one due to its malleability.  While I note the views of various members on the disadvantages of using Sundeala, it is the material the baseboard is made of and that is the problem I have to solve.  As to the location, it has been stored at the back of the garage since its delivery for a good couple of years now.  I think the only real problem is the cold in winter.  Its not unduly warm in the summer and does not suffer from damp.

Rhobat

[Graeme Dunbar]

Sorry Rhobat - got your name wrong! If the gap is only 1 - 2 mm after lengthy storage, you have little to fear.

[rhobat bryn]

Do I take it then that the Plasticine will do the job?

[Graeme Dunbar]

With gaps that narrow, I would have thought they would be covered by whatever scenery it is that is going on top. Even loose ballast is unlikely to disappear down it to any great extent.

With a gap as narrow as 1 mm it could be difficult to push Plasticine into it.

How about gummed brown paper tape as sold in Art shops for sealing the back of framed watercolours or a home-made equivalent if you want to prevent things disappearing down the cracks?
http://painting.about.com/od/artglossaryg/g/defgumbrowntape.htm

[Tigger]

For what it's worth!  For larger gaps I've used thin strips of foam plastic.  On the old MRC layout 'Bishop's Hemingway' we used to use Woodland Scenics pulverised foam rubber of appropriate colour.  Because it's fairly light we found it would fill a gap fairly well and of course, on an exhibition layout we considered it expendable.