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Most people use PVA glue, I believe. You’ll find useful info on this in the articles section. Remember, though, that PVA glues are not simply mechanical, and don’t just stick any surface to any other surface. They only work fully when they can penetrate the grain of both pieces. So end grain joins will not hold much, and cross-grain joins are not as strong as parallel grain joins. The strongest join on planking, then, will always be the join between two consecutive plank edges. The join between the plank and the bulkhead or frame will depend on the kind of grain of the bulkhead or frame at the point of contact.

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Which kind of glue sort of depends on if you can clamp the plank in place.  If you have room to clamp than a good white glue like Elmer's Glue All will work fine although druxey's comments about pre-bending the plank is also a good idea.

If you can't clamp the work than you will need mechanical fastenings like nails to hold everything together until the glue can dry.  Another way is to use CA on a few areas to hold the plank tight and use PVA or white glue for the other areas. 

In addition if possible always glue the planks edge to edge.  That is the strongest bond you can get in gluing planks.

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  • 2 weeks later...

Well to put the reality spin on this - it depends upon how messy a work man you are.

Some lovely work done with just CA ..... but....

 

CA and I just dont get on - first because i stick myself to bits of wood  ( and the desk and to my tools) and i just cant seem ever to get the right quantity in the right place !

And it marks wood irretreivably if you are not careful .

 

Good old white glue gives just that bit longer time to work  - unsticks MUCH easier and overspill can easily be cleaned off as you go.

 

One practical point is that my earlier models - around thirty years old - so with "early" CA  I find the CA has crystalized especially noticeable if you have used it on rigging - !

 

But the BIG thing about planking is pre-bend  -several times - if you have to.

When you can just lay the strip on the hull and it sits where it has to naturally - THEN stick it. 

If you get the bedding right you dont need to clamp much  -a couple of rubber bands and a bit of scrap will do

 

Edited by SpyGlass
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To present the map - you choose your own route:

PVA bonds thru a polymerization reaction.  The chains have to penetrate the substance of the wood to produce a strong bond. The closer the two wood surfaces - the stronger the bond.  A force that crushes the wood fibers is something to avoid, but below that force, the stronger the clamping pressure the stronger the bond.  Total coverage of both meeting surfaces is a good goal.  Preparation of the meeting surfaces is a detail to consider. Sanding the surface with a grit finer than 220 runs the danger of leaving the surface with no substance for the polymer chains to penetrate. Sandpaper can leave the pores filled with wood flour if too fine a grit is used. Scraping leaves clean and open pores.

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Good points by Jaager. One needs to understand the mechanism of bonding of glues/cements and different types of surfaces.

 

There are two fundamental types of fitting:

 

- the parts are held together by interlocking; an example are screws, where the male and female thread interlock; this is usually the strongest joint.

- the parts are held together by a force exerted on them: an example are nails, where the friction from the compressed wood fibres keeps the nail in.

 

If the surfaces are sufficiently rough for the PVA to key-in, the glue will form an interlocking joint.

 

Cementing metal to metal or other surfaces with CA, mean to largely rely on physico-chemical interactions with certain parts of the CA molecules and the atmospheric pressure that pushes the CA onto the surface. Particularly with shear-forces, it is easy to peal off the cement.

 

For this reason it is always a good idea to provide for some interlocking. Wooden dowels combine all the different actions. Glued carpenters' joints are another example of combining the different types of actions.

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