What’s an arris anyway? Some new to woodworking might be asking this to themselves and it’s a fair enough question simply because what’s common enough vernacular in our wonder-filled woodworking world is not common in the great big world beyond our workshop doors. I just asked two people working in the office what an arris was and both had no idea. Perhaps that makes some feel better if they too did not know. The arris is the sharp corner between two adjacent planes or surfaces. The angle need not be a 90º, though mostly they will be. It can be a round plane meeting another round surface or simply a round tabletop meeting the edge at an angle. Think arête as in the top of a mountain with a stretch of ridge or just ridge alone if you like, but arête does correspond to arris as in it being the root word for both.
This morning I removed every missed arris from the two cabinets I am making in the shop. My favourite tool for in situ arris removal is the Stanley #90 bullnose plane. I straddle the plane with my hand and let the fingers and thumb centre the plane at its tilt on the corner, tracing my fingers and thumb on the adjacent surfaces. One or two strokes will remove the corners flawlessly and the bullnose stops about half an inch from the corner where no one touches or sees anyway.
So what are the reasons for, as the Americans say, breaking the edge? Well, there are many, so here we go!
As an apprentice of just 15, George said, “Knock the arrises off, Paul!” and I did what you might have just done and said, “What?”
He took his Woden #4 1/2 and took down the corner in a single swipe and said, “Less likely to get a splinter now.”
Whereas that alone is a good enough reason, we have several reasons for doing this. Furniture is rarely left square-cornered right into a sharp arris. Mass-made furniture is almost always rounded to a greater or lesser degree — usually greater. They also use moulds to take down the corners by using moulded stock so generally, they use anything from a simple side bead to a more classic mould including astragals, ogee and a massive range of others from the classical Roman era of design. It’s also common to use any combination of shapes and indeed adapt them by using only a portion of the machine cutter be that a power router, shaper or spindle moulder. Adding decoration of this type is still fairly popular but used less in some European countries than say in the USA. I put this down to the ubiquitous use and availability of the power router. If we amateur woodworkers had to mould their stock by hand then moulding wood would disappear overnight.
Handmaking is very different than machine making: throughout our process of hand-making a project like furniture it is our common practice to plane our flat faces true and then take a single swipe along the corner with a bench plane to take the arise off all four corners there and then. This minimises the possibility of splinters, takes away the hard corners that can damage other aspects of our work by a slipped piece and prepares the work for sanding where when the corners are left on, as in machining, sanding often results in splinters.
Another key reason for arris removal is one less known and less obvious. A hard corner in almost all woods is a weak corner. Because the corner is unsupported when created, any knock by bumping or dropping something against the corner or a corner against a something will almost always break. When we are in making mode we are constantly shifting the pieces from benchtop to vise, across the benchtop to leave it there while we work on another piece and also to work it into our piece. I just made two drawers for my two cabinets and I am sure I picked up the pieces for the drawer a hundred times each over the two days it took for me to mill the wood from rough stock to the finishing and fitting of the drawers. These sharp corners times four would be 2,000 times handled and remember I made two, so, 4,000 all told.
A corner of a drawer or a dovetail in its recess, a panel sliding into a groove and a dozen more such situation is indeed another ‘sticking point’. In some more resinous woods the two surfaces stick as a sort of continuous friction. Removing the arris really helps here too.
And then there is the reality that paints and varnishes when applied shrink and stretch in a single continuous movement until cured. That results in the ‘skin’ of finish being stretched to its thinnest point. If the arris is still in full form the weakened corner will not hold up to water, atmospheric humidity and spillage of liquids, damp dishcloths and such. Within a short period, the thinned corner separates and pulls in from the corner to expose the wood. A single stroke to remove the arris means a 45º and a continuous skin of equal thickness to maximise protection. Now I know some of you might say just sand off the corner and that is fine, but it is far less efficient, you create dust and the work itself is covered in unnecessary dust too. better the plane, I think! These are small and ordinary things and yet they are big and extraordinary things that make our work different.
As a closing reason, though there are many more I know of that I might add later as I sometimes do to flesh out my blog posts, I became very aware of something when I began to sell my work as a designer-maker back in the 70s. I am trying not to be sexist here but when people come into a sales area where handmade pieces are being sold, would-be buyers run their hands and fingers over the work. Half of those visitors went more meticulously by running their fingers and hands under the rims of tables, along the aprons, places like that, the under-edge corners of chairs and along the insides of door corners too.
And if those hands or fingers snagged on anything they might consider even slightly splintery or rough they never bought the pieces. Now in our work, we are concerned about the physical appearance differently than a fully machined product from the factory. Everything gets rounded over like an American two-by-four. There is little to consider crisp and precise. Huge gaps surround the doors whether recessed or overlaid and overlaid doors are inevitably made with a quarter-inch radius to a corner round over as are tabletops, the tops of sideboards, bedside tables and so on. there is a place for that but, hmm, not too much! In a kitchen where sweeping and mopping is a common occurrence, a big radius or wider bevel works great.