Industry Insights: Grain Cuts and Joints

Grain Cuts and Joints


We hope everyone is having a successful 2020 so far. This year, we wanted to give you more of a behind-the-scenes look at what makes us tick here at Shape. This month, we are spotlighting timber and a selection of details; Grain Cuts and Joints. Get in touch if you spot any nice examples of these out in the wild!

Grain Cuts

The way the timber is sliced to produce solid panels or veneers affects the resulting grain pattern, producing varying degrees of wavy to straight lines. The resulting patterns will vary between species of timber, however generally, the typical patterns outlined below should give a good indication of the most common cuts.

Lemon Tree Kitchen - Shape.jpg

Example of crown cut panels with the grain running across each cupboard front in the Lemon Tree Kitchen.

Photography by Adam Scott

Terminology:

Bookended – Whilst timber is cut in narrow planks, we often want to create panels that are larger than the width of the plank. To achieve a seamless finish, the planks are bookended, where matching sides are placed adjacent to each other, creating the illusion of a wider panel and repeating the natural pattern of the grain from leaf to leaf.

Grain Matched – When creating a set of drawer or cupboard fronts, it is important to ensure the grain runs consistently between panels. This can either be created by a single large panel (that is often created from bookmatched veneers) being cut into smaller panels, or using a crown cut to dissect the timber into matching sections, which are bookmatched to create the continuous grain pattern.

Crown Cut.jpg

Crown Cut

Also known as plain-sawn, this is produced by cutting the log in consistent straight strips across the breadth of the trunk. It is one of the most common veneer types, and produces a wavy or arcing decorative pattern in the grain. Due to the timber being cut in adjacent slices, you can achieve a good grain matched finish.

 

Rotary Cut.jpg

Rotary Cut

A rotary cut cuts the timber in a continuous spiral. As the veneer (a very thin slice of timber, that is bonded to MDF or another substrate) continues, the wavy pattern varies as the lathe traverses the tree’s growth rings. It is the most economical method of cutting as there is very little waste, however you cannot bookmatch the veneers as each section is different.

Shape+Etch+House.jpg

In the Etch House, rotary cut veneers of Douglas Fir highlight the timber’s iconic wavy grain pattern.

Photography by Adam Scott

Quarter Sawn.jpg

 

 

Quarter Sawn

Quarter sawn is the standard to produce a straight grain pattern. The log is quartered, and each quarter is then sliced in a consistent direction. As such, you can bookmatch the resulting veneers or planks.

Rift Sawn.jpg

 

 

Rift Sawn

The rift sawn produces a straight grain pattern, but unlike quarter cuts it avoids the flaking that can sometimes be seen. This is because the cuts are always made in the direction that is most accurately perpendicular to the tree’s growth rings. As not all parts of the log can be used, this is the most expensive and rare cut, and also produces the most waste.

 

Types of Joint

We use a variety of methods to join sheets and panels; some, such as dovetails, are implemented for aesthetics as well as strength; others, such as dogbone or tab joints are more practical, and are cut efficiently on our CNC machine. Below are some of the joints that we use most frequently at Shape.

160210_Fraher_RoupellSt_004.JPG

Example of a mitred edge detail on the desk of the Lambeth Marsh House.
Photography by Adam Scott
Joints.jpg

Rebate/Half Lap 

We use this joint as a way of extending the length of a panel, sheet or plank. It is one of the strongest ways of joining timber vertically. The rebate is either glued, pinned (as in diagram), or both for added strength. If joined perpendicular to each other, the joint is similar to a butt joint, however a groove is cut into one piece for added strength.

Joints.jpg

Domino/Biscuit

A domino is used for the same purpose as a rebate, or where anything might need to be joined without any visible fixings. Holes are cut in the panels that are to be joined, and the “biscuit” or “domino” is coated in glue and inserted into the holes. The panels are then clamped together and a tight bond is formed. This creates a perfectly flush joint.

Joints.jpg

 

Dovetail

The dovetail joint is an extremely strong decorative joint. It is formed from angled pins and tails that interlock to form the bond between pieces, which can be further strengthened if glue is used (note: a box joint is similar, except the pins and tails are not angled, making it slightly weaker and less decorative). It is one of the oldest joints known to humankind, pre-dating written history, and is a mark of a skilled craftsman. At Shape, we typically use this joint in decorative drawer boxes, particularly in kitchens and dressing rooms.

Sneak peek at the dovetailed drawer box in the kitchen of Artist’s House.
Photography by Adam Scott

Joints.jpg

Mitre

Mitres are typically used to join panels perpendicular to each other. 45° angles are cut into the timber which are then glued together at a 90° angle. It is more decorative than a butt joint and marginally stronger, due to a larger surface area for the glue to bond to. It also conceals the end grain if this is exposed. We frequently use this joint in exposed timber cabinets or door liners.

Shape Lemon Tree Bedroom.jpg

Example of a mitred edge details on timber detailing and inset storage boxes in the bedroom of The Lemon Tree House.
Photography by Adam Scott

Joints.jpg

Butt Joint

The butt joint is one of the simplest joins, whereby two pieces are butted together and glued. In the right application, particularly with plywood or timber with a beautiful grain, this can create a contemporary aesthetic, as it displays the end grain of the material. Dominoes and glue, or mechanical fixings such as screws can be added in non-visible locations and angles for added strength.

Shape Pier House.jpg

Butt joints used throughout the wine store in The Pier House to create an elegant and contemporary aesthetic, whilst also displaying the grain of the Walnut panels used.
Photography by Adam Scott

Joints.jpg

Lap Joint

There are a multitude of variations on the lap joint, such as the half lap, mitred half lap, cross lap (shown here), and dovetail cross lap. In a full lap joint, no material is removed from either piece so the resulting joint is the thickness of both pieces. In half laps, some material is removed from each piece, then bonded, creating the same thickness of material throughout. These half lap joints are some of the strongest joints.

Joints.jpg

Dado

Also known as a housing or trench joint, this is formed by a groove being cut all the way, or partially (known as a stopped or blind), through a panel. The second panel then slots into this groove with glue applied, and the join is formed. This is one of the strongest joints as there are three faces to bond to. We often use them to create the join between shelves and side panels in bookcases.

 

Shape Raw Spirit.jpg

Inset dado detail surrounding the sign in the Raw Spirit van, (and mitred detailing!) highlighted by the exposed grain of the plywood.
Photography by Adam Scott

Dogbone.jpg

Dogbone/Tab Joint

Unlike the above, the dogbone or tab joint is most frequently created from joining two panels that were cut on the CNC router. Named from the semi circles created from the cutting path of the router, this is how we most frequently construct cabinets. A notch is cut into one panel, whilst a protrusion is cut into the other. These two are then locked together, then either glued or mechanically fixed, or both. These create incredibly strong carsasses that are very quick to assemble.

 

Dog Bone.jpg

Example of a Dogbone joint within a Solidworks model that our designers are currently working on for an upcoming project.

 

We hope this provides an insight into some of the considerations we put towards detailing, and helps you to specify or spot these in your own projects and visits. Please get in touch via our socials below if you spot any of these out and about, we are always looking for inspiration for upcoming projects!

Have a question?


Related Articles