Deck layer folding instead of sticking

[Alex K]

Hey everyone, 

I could really use some help figuring out how to get my deck to stick to the hull of my Cutty Sark (Mini Mamoli). This is my first model ship and I am still learning terminology and even the names of the materials. Please bear with me. 

The hull is "PLA plastic with wood particles" and the deck is a paper-thin sheet/card of wood (<1mm).
Cabins are made of thicker wood: ~2mm

The instructions said simply to glue the deck to the hull so I used PVA glue to bond the deck and the hull but instead of adhering, the deck curled up and decided that it would not stick to anything. I have a few cyanoacrylate glues of different viscosities that I have not tried. 
I've since flattened the sheet of wood. I used a bit of the deck sprue which successfully adhered to the cabin sprue with PVA so it can work. It just didn't like the hull for some reason. 


Too much glue? Am I even using the correct type?
Any suggestions? 
Appreciate the help

-Alex

IMG_4572.HEIC IMG_4574.HEIC IMG_4573.HEIC

[VitusBering]

It is difficult to obtain in the US (I am not sure about Oz) but Pattex Repair works very well. I got mine from Spain if I recall correctly. It is what I use to attach veneer. It will give you better than average working time and dries clear and flexible.

 

https://www.pattexarabia.com/en/products/all-purpose-glues/pattex-repair-100-glue.html

 

Edited March 27, 2023 by VitusBering
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[Jaager]

PVA bonds are mechanical /physical bonds.  While the words dry and cure are used for the bonding process, what is happening is the "poly" part.

A catalyzed chemical reaction is occurring.  The acrylamide units are bonding into long chains.  These chains intrude into the irregular and porous surfaces of the two surfaces being bonded.

It is a physical grip by PVA chains that makes the bond. 

Metals and plastics have smooth surfaces and have no pores.  There is nothing for the PVA chains intrude into. 

For wood to wood, PVA is an excellent choice.   For wood to metal or wood to plastic, you are wasting your effort.  It ain't gonna bond.

 

CA might work, but you are bonding a large surface area and the CA on a lot of it - the earliest applied - has probably finished its chemical reaction before the entire surface has been treated.  It is just newly added bumps keeping the two surfaces from even touching.

 

Epoxy is good for wood to metal.  There are watery clear two part epoxy that have a long enough open time - if epoxy is compatible with polystyrene.

 

There are a lot of kits with inadequate instructions,  but for a kit that is using materials that are almost never used together,  materials that probably should not be used together,  materials that require a unique bonding agent,  it is unconscionable not make suggestions for an agent suitable to bond them.

Edited March 27, 2023 by Jaager

[allanyed]

Plastic to wood.  Epoxy...........after you clean the surfaces to their original condition.  You will need to hold it tight together until the epoxy cures.  

Allan