Joints in Boxes

There are quite a number of joints used in box making and each have their own advantages and drawbacks. Below are some diagrams we have created to help describe the joints along with some sample images of each.

Butt Joint

This is by far the easiest joint to make; all you need to ensure is that all surfaces are square and parallel.

Butt Joint

Unfortunately it is also the weakest joint to use in box making – unless you use some additional mechanical reinforcement to strengthen it. Typically this is either nails or screws from the flat surface into the end grain; there is no doubt that screws, in particular, make for a really strong joint but that may not be the look you are after in your box.

The other method is to use dowels; you drill from the flat surface through into the end grain, stick some glue in and bash in a tight fitting dowel.

Butt Joint and Dowel

This makes the joint heaps stronger and can also add a decorative element to your box.

Rebate Joint

Similar to the butt joint but has the advantage of an increased surface area for gluing.

Rebate Joint

More precision required for this joint but is certainly stronger and can look nice as it shows some of the end grain and still allows the use of dowels (as described above).

Rebate Joint and Dowel

Mitre Joint

It would seem that this joint is no better than the butt joint for strength – but that is not the case. The ends are cut to 45 degrees which means that the total surface area used for gluing is significantly more and is, therefore, stronger.

Mitre Joint

This is the only joint that doesn’t show any end grain; end grain can look really good but not always. We use recycled timber quite a bit and this often has cracking and defects that show in the end grain but not on the surface. The strength is not affected, purely cosmetic, it also allows for the continuity of nicely grained timber – gives a sort of wrap around effect which can look really nice.

EB002 D
View of the outside of a classic mitre joint.

Box Joint

Popular choice as it has several benefits: a large gluing surface area, tight fitting mechanical strength and, if the end grain is good, a nice decorative effect.

Box Joint

It is a time consuming joint to make by hand which is why most of the joints you see now days are machine cut. This is arguably its one big drawback; the proliferation of ‘perfect’ machine joints means it has lost a lot of its character. We still do these joints by hand; it means they are not ‘perfect’ like a mass produced machine joint but they still retain that unique element of individuality.

EB004 E
Hand cut box joints.

 

 

Dovetail Joint

This joint was traditionally used in drawers; it gave mechanical strength to the joint when you have force applied in a single direction – like the pulling and pushing of a drawer in a cabinet.

Dovetail Joint

It was used in a time when glues were poor in comparison to today’s PVA but it has lost none of its popularity – mainly due to the reputation of the joint as a mark of craftsmanship. It does require a degree of skill to cut by hand but really no more than a box joint or even a mitre. With the right type of timber the dovetail is a very decorative joint but does tend to suffer the same problem as the box joint – the proliferation of machine or router cuts. Thankfully we still cut all our dovetails by hand which adds imperfections but, more importantly, individualism and character.

EB005 F
Large, single dovetail joint.