Glueing extruded polystyrene board

[duncan]

Afternoon All

 

I am going to try making some lightweight shelves out of layers of extruded polystyrene board glued together.  It might not be rigid or strong enough for my needs, but will be light.

 

Before I start melting the board, what glue would people recommend ?  Thinking of maybe 3 layers.  PVA ?  If so, are any makes of a different formulae to cause me problems ?

 

Thanks Duncan

[john new]

Seem to  recall Evo Stick is a definite no. dissolves it.

[johndon]

PVA should be fine (I’ve used it with extruded poly before) but be aware that it’ll take far longer to dry than it usually does… 

[eldavo]

PVA requires at least one of the pieces being bonded to be absorbent and so a join between two pieces of foam will never fully cure.  I've used solvent free grip fill (Screwfix cheapo) in the past and even though that is probably PVA based it produces a pretty good join.  There are also specialist foam glues available at a cost.

 

Cheers

Dave

 

[jpendle]

I use a Woodland Scenics Hot glue gun on my XPS baseboards. I used 1” thick XPS.

Be careful if you are tempted to paint it, rattle can paint dissolves it pretty fast.

 

Regards,

 

John P

 

 

[teaky]

I assume you mean extruded PIR (Polyisocyanurate) board rather than polystyrene?  Common brand names being Celotex and Kingspan.  I have to say, it isn't the first material that comes to mind for shelves.

 

A solvent-free grab adhesive will work.  My favourite is Screwfix No Nonsense brand: https://www.screwfix.com/p/no-nonsense-grab-adhesive-solvent-free-white-310ml/87451

 

(Blimey.  I'm glad I have plenty in stock.  Last time I bought some, less than two years ago, it was half that price!)

[SamThomas]

Anything that dos not have any form of solvent in it will do the job.

 

If speed is not impoertant then PVA will be fine, if speed is important then any of the cheap "instants" will do, again, make sure they do not contain any solvent.

 

Hot glue is mot a good idea either.

[duncan]

Many thanks All

 

Teaky, it is extruded polystyrene, but it is very fine grained.  Worth a punt if it works.  I looked at melamine etc boarding, but thought it would be too heavy for the depth of shelf I want.  Also thought of Kingspan etc, but didn't want a silver foil shelf. 

[AndrueC]

PVA has always worked for me but it needs a bit of pressure. Nothing major but seems that just dropping one sheet onto another is not enough for a good bond. Also takes a while to cure. If in doubt, for scenery wrap it or cover it in Modroc. 

Edited May 22, 2022 by AndrueC

[BR60103]

I use Woodland Scenics Foam Tack Glue which is designed for this purpose. It's also sticky for other uses. I've used it for sticking track down.

 

[SamThomas]

16 hours ago, duncan said:

Also thought of Kingspan etc, but didn't want a silver foil shelf. 

You can peel it off - but peel off both sides otherwise it tends to warp as the manufacturing process puts on under tension when the foil is applied.

[DCB]

Just wondering what is going on the shelves?  A few plastic kits?    Wood is a good alternative, I like tongue and groove cladding, surprisingly strong compared to Melamine and a lot nicer to look at than plywood.   I (ab?) Used it to re roof my shed! and  made shelves about 4ft long X 1ft braced only at the ends holding up to around 20  off  00 coaches side by side with no immediate signs of distress.  The cabinet we bought had melamine 3 or 4 " wide X 3ft or 1 M long and they have all sagged so replacement is imminent just as soon as I can scrounge another pallet.  

 

[duncan]

Yes, some rather large plastic planes, so not much weight.  Don't want heavy shelves (avoiding heavy fixing plugs), especially as they will be fairly deep.  If the expanded poly does not work, then could try light tongue & groove.

[Richard_A]

Try a polyurethane glue, it is incredibly strong. 

 

It does foam slightly so anything getting glued together would need to be weighted down. 

[Solo]

On 23/05/2022 at 02:45, BR60103 said:

I use Woodland Scenics Foam Tack Glue which is designed for this purpose. It's also sticky for other uses. I've used it for sticking track down.

 

I second this - I've used it for almost everything on various scenic test pieces and now starting a layout build.  It certainly seems to do the job with all kinds of foam and will also do wood and plastic rather nicely.  WS products whilst not the cheapest seem to all be first rate.

[duncan]

Many thanks All