Foam (Celotex, Knauf? Recticel etc) again.

[MalcolmInN]

So the time has come for me to stop experimenting on the table top with ovals and inglenooks on corrugated cardboard (!) and move up a notch

First Q ) Do you know of any of the DIY chains that supply single boards of insulation and will cut to size for me ? B&Q, Wickes etc. ?? eg. 6 or 8 ft by 30inch.
My local diy will cut plywood and timber for me *, but only supplies insulation boards to builders in multipacks  :'(

* I may eventually go the 'plywood with timber frame' route (when I achieve full control over what will become the railway cave ), but the foam sounds good and light weight for now.

Thanks for reading/suggestions,
meanwhile I'll continue my "Foam" searching the forum > > >

[Kris]

Wickes and some B&Q's certainly will supply single sheets of insulation. No idea if they will cut it as I have never asked them to.

[trkilliman]

Celotex etc is easily cut with a carving knife and straight edge. I used it to insulate my tropical fish house. I suggest you skulk around a new housing site and ask for some offcuts. It's used extensively nowadays, and for the price of a couple of pints you could walk away with more offcuts than you could ever use.

[Adrian]

What are you going to use to glue this material, Malcolm?

Applied as a layer, say to ply, and using say PVA to fix the two .......... The foam won't let air through, so away from the edges the glue can't cure.

Uhu Por is the stuff to use on a spot basis but is expensive and very difficult to use over a larger area.

Very interested to hear what your research has revealed on the subject

Kind regards

Adrian

[REGP]

My local Wickes still stocks some 6mm insulation foam in sheets 1.2mtrs by half metre [40x20  inches]
is that any good? You can stick 2 sheets together using no nails.

Ray

[MalcolmInN]

Celotex etc is easily cut with a carving knife
skulk

Ah thank you, interesting, I had thought that with a layer of fibreglass in the sandwich that it would not be easy, good, so I could do a rough split in a car park and trim it correctly when I get it home.
(all so as I can get it in my car rather than call on a mate with his trailer ! )
I do like a good skulking as well

What are you going to use to glue this material, Malcolm?
,
what your research has revealed on the subject

early days on research,, lot of historical stuff on RMweb, but my head hurts , they I think were using no-more-nails or something like that, not to glue a top on, to glue plywood round the edges for protecton during transport not for structure. There was also a lot about peeling off the foil, not just on one surface ( else it would warp) but on both or neither. Not sure if they ever reached a consensus on which was best all or none. My 1 remaining brain cell couldnt take any more.
So I claim sanctuary here LOL!
Some of all that was going to be my next few questions after I sorted my first one

My local Wickes still stocks some 6mm insulation foam in sheets 1.2mtrs by half metre [40x20  inches]
is that any good? You can stick 2 sheets together using no nails.

Ah, no nails, that was it ! Good man.
stick the 2 on their edges ? That would need a supporting top ( or bottom) then ?? prob. ? Would probably be good enough for a Gumstump, but maybe not for developing my ovals.

Thanks everyone,
very helpful.

[Babz]

Hello Good Evening I hope you do not mind me joining In on this subject, We had our loft converted  properly at the end of last year and we used celotex board you must leave a gap between the Celotex and your roof Felt as you need the air to circulate round the building ours was 50mm thick and it came flush with the forward edge of the Loft truss, they then covered it with a foil sheet so to speak allover the trusses and then plasterboarded over that and the remarkable thing was no heating required in winter and in the last week the temp was really good in the loft around 20c
When we are at home we leave the loft hatch open as i spend a lot of time up there during the week days doing my loft layout It was the Building control  inspector who gave us the nod on how it should be done to meet the requirements.

Babs

[MalcolmInN]

Hello Good Evening I hope you do not mind me joining In on this subject,
,
doing my loft layout It was the Building control  inspector who gave us the nod on how it should be done to meet the requirements.

And good evening to you too Babs welcome aboard
A sort of similar tale to tell this end -
I am kicking myself for not cottoning on earlier, my daughter, with help from her friends 90% demolished a house and then rebuilt it to modern mortgageable standard should she ever need, in the future, to mortgage it; including in that, whilst they were about it, added a quite large two story extension  with masses of Celotex involved, as you describe !!!
Argh I am a numpty ! I think all the offcuts are long gone

But the other similarity is the help they got from the building inspector, quite the opposite of the usual TV portrayal of the jobsworth. He suggested how and what they could do themselves and what certifications would ( in that eventuality) be needed by mortgage companies, and what certifications/standards were required by the BI.
All very satisfactory all round, so all I need to do now is tell her friends what size off-cuts, from future jobs, I will need for my humble little playthings

Assuming that she dont, with bit between her teeth, start on our house next, LOL!

[Ancient Hermit]

Malcolm,

for a join I would try Devcon 5 minute epoxy. It has seldom let me down - I'd also get a couple of pencils and sharpen both ends and use them as dowels (use ordinary dowels if you are feeling flush!) - put boards down next to each other, hold dowels in the gap, then close the gap - that would quite probably work out!

Ideally bandage the join, but in this case that's not going to help as you need a flat surface - well at least on the top I guess....

This is roughly how foam core wings are secured on RC planes, or at least it was if not now. (probably got something ten times more expensive by now) 

[MalcolmInN]

get a couple of pencils and sharpen both ends and use them as dowels (use ordinary dowels if you are feeling flush!)

Pencils what a good idea!  and we can leave the flush in the you know where
So all I (we) would need is a flat level surface to do the assembly of smaller offcuts, or Wickes small panels, and put a 2" (or thereabouts ) surround of plywood, thus adding vertical rigidity as a bonus.

Ah that reminds me ,, Adrian > in my researches someone suggested that the surrounding plywood walls could be made an inch or two higher than the contained foam, thus acting as a barrier to the well known 'flying loco' syndrome
and I suppose some suitably formed curves would give legs at the corners ?
Hmmm, thinking aloud - probably easier to incorporate more, vertical this time dowels   stout pencils

Derruh, did someone say  "Devcon 5 minute" warning,  eeek to the shelters everyone > > > 

[Dorsetmike]

I've used 1200x450 (4'x18") 50mm Celotex sheets from Wickes for my layout 9'6" x 2'6", it cuts very easily with a carving or bread knife, it makes very little mess (unlike the expanded polystyrene).

Ive used double sided carpet  tape in some places, Nonails in others.

[MalcolmInN]

I've used 1200x450 (4'x18") 50mm Celotex sheets from Wickes for my layout 9'6" x 2'6", it cuts very easily with a carving or bread knife, it makes very little mess (unlike the expanded polystyrene).

Ive used double sided carpet  tape in some places, Nonails in others.

thanks Mike,  this all begins to look more 'n more doable

[georgehgv]

Malcolm,

for a join I would try Devcon 5 minute epoxy. It has seldom let me down - I'd also get a couple of pencils and sharpen both ends and use them as dowels (use ordinary dowels if you are feeling flush!) - put boards down next to each other, hold dowels in the gap, then close the gap - that would quite probably work out!

Ideally bandage the join, but in this case that's not going to help as you need a flat surface - well at least on the top I guess....

This is roughly how foam core wings are secured on RC planes, or at least it was if not now. (probably got something ten times more expensive by now) 

I look forward to reading about a remote controlled airborne flying layout constructed from glued together bits of Celotex, please record this or upload to YouTube, and please give Newport Nobby a nod as this sounds right over his street! 

[Dorsetmike]

Rereading the thread I see a suggestion for "bandaging" the join, I laid cork flooring tiles over mine again fixed with double sided tape that gave me a good flat surface and also better for holding track pins.

[smg id=24929]

For edging I used lengths of timber cladding, a little thicker than ply, plus doesn't need cutting to height, screwed to the base frame and Nonails to the Celotex

[smg id=24973]

The Celotex can also be used for gradients, I was going to use the Woodland Scenics gradient sets but the local shop didn't have them in stock and being an impatient B I decided to make my own.

[rhysapthomas]

Good looking layouts  Just to endorse everything said here I had a piece left over after an extension and it cuts easily with a bread knife and the foil layers can easily be stripped off

I have just bought 10 off sheets of the 450 by 1200 50mm celotex from Wicks at a price of £4.19 each for 5 which oddly is a better price per sq m than buying the larger sheet 2400 by 1200

Also it can be used to make rock faces