Hi guys just a quick intro Ant from New Zealand

[Antnz]

Oh i meant to ask

Polystyrene now i know its not recommended but you can buy sheets of ten in a packet here at a reasonable price and they are the same size as my sections.I was thinking of gluing it onto my 12mm ply top.Now its 25mm thick which is why i am asking now ass it will affect the length of my legs or height of the baseboard,so i will have to allow for it.

I was looking at the poly because i can bed my river into it and also bed the buildings etc into it also.

The other insulation materials you guys use are way expensive here.

 

Cheers

Ant

[cteno4]

Ant,

 

there are two kinds of polystyrene insulations, extruded and beaded. The beaded is harder to form as the beads tend to fall apart as you sand or cut it. The beaded is also softer than the extruded. The extruded is denser and forms better contours with sanding or cutting. Not sure which yours in in the 10 pack.

 

jeff

[Antnz]

Jeff,

 

I'm afraid what i am looking at is beaded which is why its so much cheaper i am thinking.The extruded looks a lot better but is far more expensive for a lot less material.

 

Just wondering if its worth putting down the beaded polystyrene as a base layer or not ??.

 

Ant

[cteno4]

Ant,

 

before you leap into the beaded foam, I would experiment some to see if you are happy with it as a modeling substrate. Some do fine with it and some really hate the stuff. Using it as a substrate all over the layout will allow you to dig down where needed. Downside is you will need to probably use caulk or PVA glue to put your track down to the foam. Bit less forgiving if you need to move or replace track. PVA you can try to use water to lift up later, but the downside is it’s a hard glue and some find it can make more transfer of train noise to your substrate. Some think caulk helps dampen this.

 

have you thought of the scenery techniques you will use to build your scenery up? This may help in the substrate decision.

 

I’ve used the extruded polystryene a lot and really love it. It’s more expensive but so stiff and works very well for sculpting and structurally is super strong. I’ve built many modules for the club and members that just use extruded polystyrene as the whole substrate layer with just a frame and some cross bracing under the polystyrene. This removes the need for the 12mm ply (and having to drill through it for wiring and such and the cost) and lightens thing up greatly. 25mm extruded polystyrene alone can be the substrate with no plywood base. Just frame each module in like 75mmx18mm material and put like 3 cross pieces per module at 50mmx18mm under the polystyrene. You might get a chunk of 25mm extruded polystyrene and experiment a little. It may cost more for the extruded polystyrene, but savings in no plywood layer and simplifying build some. With your size modules even 12mm ply will need a little support fro some cross pieces under it. Also you will reduce weight a lot w.o the plywood and lighter means less leg support needed.

 

removing the plywood layer also helps remove the need to cut the plywood needed for each module (don’t know how much of a wood shop you have). It’s reduced to just chopping off dimensional stock to make a frame and cross supports for the foam board.

 

just some ideas to gnaw on.

 

cheers

 

jeff

[Antnz]

Jeff,

 

That,s a lot to think on jeff but i will do just that.I will have another look around and see whats available and inquire in store.

 

Ant

[cteno4]

Might get a piece of each kind and see how you like it and glue some track to it to see how it works for you. The extruded is a very stiff and sturdy board, the beaded much less so. Extruded also cuts very cleanly (ie nice edge, the beaded hard to get a clean edge. Both are very messy to cut and shape as fhe polystyrene gets statically charged and sticks to everything, so best work with a vacuum running! You can also use hot knife/wire cutters as well,mbut these will leave a sort of hard edge from some of the melted polystryene that then can make sanding and rasping hard around it. Of course with hot cutter you need lots of ventilation due to the fumes. I’ve always preferred serrated steak knives to shape up extruded foam over hot knives.

 

here in the us, extruded polystryene insulation use goes by building codes and is not available on some warm weather areas as not commonly needed. But one place it’s used a lot is in insulating walk-in refrigerators and freezers, so some have sourced it thru a refrigeration companies if not at builders’ supply places.

 

there is also polyurethane insulation that is sort of brownish and many times has a silver reflective paper on both sides. This doesn’t work well in modeling as it’s pretty soft and the paper coating makes it harder to work with.

 

reason I recommend getting some small bits to play with is with stuff like this it’s a lot of how it works in your hands!

 

Keeping the bench work light will help, no reason to overbuild things. A rail attached along the wall can support the back half and give you lateral support. Legs could just be rectangles of like 35mm square stock that just fit in at your module joints and attach to the wall in back (put a vertical runner up the wall to easily attach to. This would give you maximum storage space and access under the layout. Top of the vertical support rectangle could have a wider flat piece of wood attached (or just be the top piece) like 75mm or so wide to grab both module frame ends well.

 

cheers,

 

jeff

[Antnz]

Cheers Jeff

 

I will aim at keeping my framing light weight.

 

I have had a good look around today not a lot of the extruded polystyrene about,but my local hardware store does stock  extruded polystyrene at 2500mm x 600mm x 10 mm

$17.16 NZ a sheet,a bit thin.

But trying to think outside the square i was wondering if to use the beaded poly 25mm as a base and plop the extruded on top of that.Just thick enough for a river depth.

Or perhaps double up on the extruded but not shore if it would be stable enough on its own without sagging.

 

The beaded has the thickness but the extruded has the work ability but thin.

 

I hear what your saying about the beaded.I have drowned in the stuff here in packaging etc and yes it doesn't cut nicely and very very messy.But just wondering if for the base ( sandwich ) i may get away with it.

 

Having said all that im still investigating.

 

Ant

[cteno4]

Ant,

 

not a bad price, but 10mm is not going to be stiff enough for a base alone. You could back this with like 5mm ply if 10mm is deep enough to dig into for scenery dips. 25mm is when extruded gets stiff enough to be structural with a frame and a few cross supports underneath. Might call around to contractor/builder supply stores to see what they have.

 

laminating to the beaded i doubt would be stiff enough, might be, but laminating the foams would be a pain, probably have to be contact adhesive as you can’t use things like PVA that need moisture to escape to cure as can’t do that well with two plastic layers. plywood to polystyrene would probably work with PVA as moisture could go into the wood layer.

 

jeff

[Antnz]

Jeff

 

I have put out some feelers for extruded so we will see who e-mails back.

 

I can see the benefits of it especially with what i want to do on my layout.

 

Ant

[Antnz]

Just a quick update

 

Its been very interesting searching for extruded polystyrene.

I have had one reply to date,they suggested i look at what was stocked in store or they could order in for me.But i could not seem to explain to them that there is a difference between extruded and expanded,expanded being what is stocked locally.

 

Most or all stocked items seem to be expanded products and seems to be what is used as the main insulator here in New Zealand.

 

Contacting the big suppliers has had little result,as they do not sell to the public,you are passed on to your local retailer who stock what is most popular and don't seem keen to order in for you,the answer from them being we order in what is already stocked in store.

 

I did find a product called Depron,which seems to be XPS or similar.It seems to be mainly used by model plane builders and has a paper coating.

 

The upshot is at the moment seems to be to use expanded and make it work for me.

Which means using a 12mm ply base with a 25mm expanded layer on top,so i can work down into that layer.

 

My other option being to raise the track,which i hadn't thought about before, raises a few problems but not insurmountable.Seems to be a lot easier than digging down into the sheet.

 

There is a product ( which im not sure im aloud to mention ) that produces pre formed risers readily available but expensive.

 

Or make my own with 25mm expanded poly ( cut into strips to suite track width )( or 50mm with two layers ) so i have scenery below and above the track.As its just to raise the track this may be easier and yes cheaper.

 

Googling around ( all weekend LOL )i have found im not the only one with this problem,and ive now seen more than a few pictures of track raised by every method lol with untold amounts of every type of foam stuffed underneath it.

 

I should add that im looking at plastering the foam with plaster cloth.

 

That;s where im at,at the moment.

 

Ant

[cteno4]

Ant,

 

interesting they have the extruded in 12mm but no other sizes. 
 

the old way to do raised tracks to do variable height scenery around the tracks was to cut a plywood or masonite base a bit wider than the track and then prop it up with blocks underneath to the desired track height. The layout base usually was a grid of framework and upright boards are screwed to the framework to the desired height above the framework and track base attached to the top of the boards. This makes it easy to do grades as well. Then usually wire mesh was stapled from track base down to wood blocks coming up from the base framework to make your landscape shape. Then plaster was applied to the mesh. Newer methods use cardboard risers in the contour of the landscape coming up from the base frames. The  strips of cardboard are glued along the top of the contour risers. Then over this strips of butcher paper soaked in plaster on top of that to make a rough shell. On top of this plaster or plaster cloth to finish off.

 

you can easily cut the track base pieces using a small power hand sabersaw. This may be a better option if you want to have lots of undulating scenery as digging out your expanded forms could be a lot of work and not the best stuff to lay track on.
 

5mm ply would be fine for either under the 25mm expanded foam or as a cut out track base. 12mm is more than you need and just adds weight to everything (and cost). A great 5mm ply is called luan ply. It’s a South Pacific semi hard wood and very moisture resistant. It usually has thicker outer plys than regular plywoods. It’s used as underlaminent in bathroom floors a lot as it can bend a little to smooth over small imperfections in the subfloor and it’s very impervious to water.

 

cheers,

 

jeff

[Antnz]

Jeff

Thank you for hanging in there with me,this must be like Deja vu for you with us beginners.

 

I have spent the last few days looking hard at baseboard construction and re reading your posts.I had a good read up on L girder construction and many other forms of construction.

 

Looking at what materials are available to me and what isn't . ( including luan ply,had a good look but could not find it any where )

 

My thinking is timber open frame

With 7mm pine ply top ( a saving of $60 NZ over the 12mm )

Using Woodland Scenics risers and inclines to raise the track.This seems the easiest solution for me ( as a beginner )for raising the track.More expensive but only used where needed.

Using the expanded poly for building up scenery and hills.

 

I'm looking at leaving the both station areas on the flat on ply,so im only raising the track on the top curves ( top left and top right,and over the river areas ).

 

I can get latex glue for gluing all poly down to the ply.

 

Thats where im at,i have altered my plan a little to allow for a longer run to raise the track into the right hand curve,but a wont tinker to much until i see everything laid out. 

 

hope that's explanatory

 

Ant

[cteno4]

Ant,

 

no worries at all, that’s what JNS forum is all about! 
 

glad you read up on the different approaches. L girder is nice if you are doing a lot of sophisticated grades as you can really control them and then do the 3D sculpting in between. But it is a lot of work on the sub roadbed construction.

 

woodland scenics are nice and simple if their grades fit your needs.

 

7mm ply is good. If your modules are 1m deep I’d say put a cross piece on your framework every 30cm. Remember to drill some lime 1” holes in the cross pieces (like 5 all along the center of the cross piece) to run your wiring through them. They are hard to drill once the frame is all assembled.

 

on your frame if you want to hide the plywood edge you can have your cross pieces 7mm below the top of the outer frame so the ply sits down flush with the top of the outer frame. Then glue some small like 10x10mm strips in the corners along the end to attach the plywood at the ends to the frame. You can do this between he cross pieces as well. Little bit more work but makes for a very nice edge on the layout. Other option is just attach the plywood to the top of the frame and later put a piece of trim hardwood plywood or veneer over the full face of the frame and ply edge.

 

experiment with the glues with the foam to foam and foam to ply. A trick for laminating the foam layers is to glue them together then shove bamboo skewers through the foam layers at different angles. Helps hold it all together while the glue sets up. 60 grit sandpaper wrapped around your finger will quickly shape the xps roughly, then finer grits for smoothing. Layer of plaster cloth or dilute plaster painted on can make a good scenery shell.

 

sounds like you are focusing on on what will work best for you!

 

looking forward to how this all evolves!

 

cheers

 

jeff

[Rod.H]

XPS foam in Australia is getting difficult to source, we used to be able to rock up to Bunnings, get a snag and a carload of foam sheets. There's now only one producer of xps foam I'm aware of. No idea on how you can buy it and they only offer one size 2400mm by 600mm but 6 thicknesses 25, 30, 40, 50, 60 & 75mm. 

[cteno4]

Thanks Rod, that was what I suspected. Some regions in the us no longer carry extruded polystyrene as well as it’s no in the local building codes for usual insulation use. Some of those places still use it in specialty refrigeration, but then not sold through the usual channels.

 

jeff

[Antnz]

Cheers guys

 

That's interesting i was beginning to think that i hadn't looked hard enough.Bunnings has become my go to local store,we have had them here now in NZ for a few years,and being Australian owned  have a larger stock of hard to find goods.I think with shipping costs increasing that has eased of considerably.

 

I looked at XPS a few months ago and yes bunnings had it in stock,but i hadn't started my framing so left it alone,now im kicking myself as it isn't stocked now.

 

A few places were offering 2400mm by 600mm at varying thickness and offered to cut in half for ease of cartage.Now they don't even reply to your inquiries.

 

Never mind i am happier in my mind having decided on the woodland scenics product and good old ply baseboard.

 

Ant

[Oxbox]

I think some of the foam scarcity here in NZ is due to how relatively recent the insulation standards increases are, the stuff just was not needed/wanted other than in infrequent niche use cases. It has been endlessly frustrating for me trying to get pink foam here (not just for modeling) which was readily and cheaply available back in the states...