baseboards

*** I often try to keep things simple and promote "best practice" and agree that quality ply makes the best baseboard, and its perhaps the only material to use for exhibition layouts where weight, stability and reliability/toughness are important.

The cost penalty in many parts of the world is scary prices for good quality ply.... Good ply is quite expensive but putting it in perspective, the real total layout cost difference is less than the price of one small loco - a small cost to pay for a whole layouts reliability!

But - I don't write MDF off at all - depending on where you live, for a layout that will never move, MDF is a very good material for baseboards. Easy to use with an excellent surface stability but its heavy. Its used very commonly with success for layouts however it really does need sealing on all surfaces and edges for longest life/stability. However - so does Ply for best layout life & results.... Overall I'd say that by direct personal experience, MDF is at least as stable as average quality ply - but perhaps not as good as good quality ply.

It is definately more suitable for drier climates or inside/climate controlled areas than sheds or lofts without lining - for those less than perfect places I'd completely agree with Tim and use Ply when possible - but not cheap stuff... good quality ply only.

One tip that will help new layout builders a lot: Most of the "rail gap" problems we have are because of unsealed wood - when its hot, the wood drys and shrinks and the rail expands, making rail buckle - the wood moves about 5x as much as the rail, so painting sheets all over before using or cutting then re-sealing the edges should be a priority for all baseboards.

Yes, I think you are right Tim - in any materials, there will be lots who had layout problems but don't confess to them as nobody want to appear foolish, but I really think its mostly just not using the materials properly thats the problem, not the material itself.

Health wise:

All hardwoods are bad for you dust wise, mainly because hardwood dust is very fine compared to pine etc... and modern high quality ply has synthetic resins used for glue which are almost the same as the bonding agents used in MDF.

The reality of this is that common sense says always wear a mask when using a power saw or sanding anything.... I have a mask and when I forget or don't bother I always end up paying for it with sinus issues for the next 24 hours!

Richard

Thanks to all for advice and info.

I have this morning changed my order to Chinese Hardwood faced WBP 9mm Plywood which is "suitable for Structural end use" and conforms to BS6566. I have used 6mm of this grade in the past for other uses without problems, so I think the 9mm sheets will be fine for baseboard construction.

I will bear in mind what Richard has to say about sealing the boards and track roadbeds when cut....I would use slightly diluted clear polyurethane satin varnish....agreed?

QUOTE (TimP @ 7 Jan 2009, 18:46) <{POST_SNAPBACK}>H Richard,

interested in what you say about painting the wood - will that really help?

Also What do you paint them with?

Cheers

Tim

Hi Tim

Sealing the wood (on all sides) stops moisture getting in , In earlier times wardrobes and household furniture etc was made of ply over frames held together with dowels .these were varnished inside and out then laminate was glued on the outside.
Many of these old wardrobes from the 60's and 70's are still found in excellent condition even when stored in sheds and garages and other damp areas for years.

Of coarse - do that with a modern version and it will turn into wheetbix after a few years

- Polyurethane varnish would be perfect , just make sure it is all covered.

Regards

Zmil

Thanks Trevor,

I have just had the boards delivered....they look fine, just what I originally expected.....really glad I joined this forum. Friendly folk here have stopped me making an expensive mistake as I take my first faltering steps in layout construction.

Almost finished my outline plans of where the tracks, turnouts, crossovers are going to be (I think I am on version 21 already!)....tomorrow I will be cutting the main baseboards into 8x3s and 8x2.5s in order to get them into the attic. I plan to lay them flat on the floor to allow them to acclimatise before any construction takes place (as with the timber also). On the boards I will draw the straights (Peco streamline) and place printouts of the turnouts, etc so that I can check that the paper plans fit in reality and also to mark out where the turnout motors need to be in order to avoid placing crossmember joists there.

I will continue the story as it unfolds. I daresay I will be seeking advice again in the not too distant future!

Regards,
Brendan

*** Thanks Tim - I really didn't realise the Venom had a wood substructure - I just spent some time looking at the details and reading a little about it. Its certainly an aircraft with an interesting service history.

I'm not really worried about the H&S having been around timber of all kinds for many years but no longer use MDF for layout use other than for big backscene sheets where its smooth surface works well. A couple of friends have large almost totally MDF based layouts that are very stable and run well but the atmosphere here is very MDF friendly.... and the termites don't like it too much either.

(I do know of one local "shed based" layout that was written off by termites which ate away at the softwood frame and bracing - a real shame!

I do like using ply and it'd be nice if we could get birch ply easily down here, but its a Northern hemisphere timber and ply ex EU is quite rare. After a little experimentation showed that the saving in using lower cost Asian ply just wasn't worth it, I tend to use marine ply which is dear but at least always nice quality.

kind regards

Richard

QUOTE (patrick draper @ 7 Jan 2009, 10:31) <{POST_SNAPBACK}>I use Sundela for my layout, it is expesive but is easily worked with and also does not warp. Mine has been in my loft for 25 years and still going strong. Any undulations can be easily sorted out or indeed added.
I find that anything too hard such as MDF and Ply are difficult to work with, not an insurmountable problem but annoying at times.

If you used the right material (ie ply), you wouldn't have to sort out 'any undulations'. This is exactly the problem of Sundeala - it's just not suitable for the job.

I personally, wouldn't use MDF because, not only is it heavy, but it is also very susceptible to moisture damage - mainly relevant to the surface. I wouldn't trust sealing it - you've only got to put one pin or screw through it and the seal is broken. In structural terms it is fine however.

The only problem with ply is that it is no good for the 'track pin brigade'. If you glue a cork track bed down and then glue your track to the cork, ply is fine.

Graham Plowman

QUOTE (72C @ 7 Jan 2009, 17:12) <{POST_SNAPBACK}>What is the attraction of any particle board such as Sundela, did someone back in the 60's who wrote in the model press have shares in the company?

All particle boards absorb water, the UK is a damp climate and our layout rooms tend not to be the prime habitable room within the property.

Particle boards tend to create carcinogenic airborne particles when sanded or cut (MDF is particularly bad) and need extra bracing compared to plywood.

No doubt there is someone with a layout made from chipboard with 2"x1" bracing that has absolutely no problems and I am sure that there a lot more guys who wished that they had used decent plywood but chose not to admit it.

72C,

The attraction of Sundeala is because it has been promoted by Peco as a baseboard material (and used on all their layouts at Pecorama) for many years and Sundeala, naturally advertise in Railway Modeller, Peco's publication.
It is an awful material for all the reasons you indicate. Advocates of it will tell you that if you add more support, it's OK, but my experience over the years of having to help people out of their 'Sundeala disasters' has been that no matter what you do to it, Sundeala always finds a way to curl at the edges, warp, bulge or sag. It's already expensive and by the time you add up the cost of all the extra support (which won't solve its problems anyway), you'll find that you've spent more money than you would have had you gone ply in the first place.
The only thing I am pleased to say is that the stuff is only available in the UK and that the rest of the world doesn't have to suffer from the stuff!!
The only good property of Sundeala is that it's great for the 'track pin brigade'.
I came across far more failures with Sundeala than successes when I lived in the UK, but you are right, people choose not to admit the failures!

Like Richard Johnson, I am a strong advocate of encouraging 'best practice' and like him, it's 12mm ply for me.

Graham Plowman