Knot

PART VI - CONSTRUCTING THE FRAME

This is one of my favourite stages of any bespoke creation. Until this stage, the design has existed as sketches on paper and sterile 3D renders. After that, a collection of unconnected components waiting to be joined together and given meaning. Its also one of the most stressful times in the creation process - the amount of work, care and skill that has been imbued to each part grows throughout time - one wrong step at this point can cause a huge amount of trouble whether remaking parts or fixing damage.

Once fully shaped, each pedestal needed to be levelled so it sits stably on the floor, and the tabletop is fully supported once in place. My low angle jack plane doesn’t get a huge amount of use, but here it is perfect for providing the perfect finish on end grain oak, given the low angle of attach. Chamfering the edges first and skewing the blade provide protection against any tear out at the edges.

The under frame for the table is a simple H shape, but the strength of the connections are vital. At nearly 3m long, the tabletop needs to be fully supported without flexing, and the pedestals need to be held tight to prevent any racking of the frame. The frame was constructed using one of the strongest joints around - a shouldered cross halving joint. Simple halving joints substantially weaken each component and are often unsightly if not perfectly cut. They also provide no resistance to twisting of an individual component. The housed joint increases the joint strength exponentially.

NEXT UP - Creating the Surface

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PART V - PROFILING

Once the full pedestal base had been glued up, it was time to apply the edge detailing to each outside edge. As these were milled up identically to the inside staves, I needed to transform a sharply angled surface into a smooth roundover. As the thickness of the timber increases from top to bottom of the design, the simplest way to manage this is to mark the desired profile onto the end grain at the top and the bottom, and take to the hand tools.

Once marked out, I added a series of tangential lines that represent the 45 degree chamfers that can easily be removed without ruining the profile. Once this is complete I repeated the process to add lines at 22.5 and 67.5 degrees and flattened these. Once complete, I was left with a tapering octagonal shape. Removing the high points left me with a roughed out fully round shape. From here, the form is refined mostly by touch and removing small ridges where the hand feels them. Finally, a long strip of sandpaper can be used to ensure a perfectly smooth transition.

For most of this operation a block plane was the best tool, as shown in the video. The adjustable mouth and fine blade adjustment meant that I could not only control the depth of cut but avoid any tearout. The were a few sections with concave profile that needed me to change to a curved spokeshave and some really tight corners at the very top of the pedestal that needed the fine touch of a Sloyd knife.

UP NEXT - Construction

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PART IV - SHAPING THE PEDESTAL

To create the desired ripple effect, each stave was CNCed on both sides. This presents challenges for work holding and indexing to ensure both carved faces meet as desired. From the CAD model I created for the initial design for the client, we CNC machined some mating jigs out of MDF. Once the first side was carved, the carving blanks could be flipped onto their mating MDF jig. MDF being quite air porous, the vacuum table of the CNC can hold the part firmly down without the need for screws, meaning that the whole surface can be carved without obstruction.

Once fully carved, the staves were glued up in pairs to make the process manageable. The initial pairs were relatively simple as the centre of the glue line coincided with the outer edges where clamping pressure could be applied. Each subsequent glue became more and more complicated as the centre of the glued faces moved further and further away from the centre line of the overall shape where clamping pressure could be applied.

CNC machines are fantastic for fast and accurate milling of timber. However, they have two significant shortcomings when it comes to machining components for high-end bespoke furniture. First, the machines have no concept of the grain of timber. The machines were initially created to machine homogenous materials - steel, aluminium, polymers. Timber is quite different in that the direction of machining (for example across the grain or along the grain) will have a large impact on the quality of finish achieved. Secondly, when machining rolling curves like the components shown here, the stepover of the cutter head leaves small ridges in the finished surface that need to be removed. For these parts it’s not practical to get a sander into all the nooks and crannies, so a well tuned card scraper (actually, several in different shapes) is perfect for the job.

Next up - Edge Profiling

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PART III - CREATING THE PEDESTAL

Each table base is made up of 6 identical (save the profiling of the outside edges) tapering trapezoid profiles. Due to the scale of the table being made, the staves are laminated up from 2” boards giving a total thickness of over 90mm - maximising the saw blade height of our huge Altendorf saw in the workshop.

Each piece tapers on a compound angle. In these circumstances it’s worth spending a little extra time to make sure the joinery can be perfect first time. Several jigs were made to hold each blank correctly - the skew of the jig accounted for the tapering across the length - the tilt of the saw blade cutting the bevel so that each blank mates perfectly to the next. The combination of a vice-tight jig and newly sharpened rip blade meant that the surfaces were good enough to glue straight off the saw - a massive relief as hand or machine planing at this stage would almost certainly introduce inaccuracies, and therefore compromise strength.

As both the inside and outside faces would receive a profiled face before glue up, I machined a shallow groove into each of the glue faces. This adds nothing to the strength of the joint, as one might often associate with timber splines on for example a mitre joint. The large amount of face grain to face grain contact in the joint means that no additional strength is required. Moreover, these grooves are used to locate one stave perfectly against its neighbour, meaning minimal cleanup is needed when the profiled components are glued together.

The resultant structure resembles a wigwam, wider at the bottom tapering to a near point at the top. Due to the nature of the design, the radii of the curves on the inside and outside of each profile change as you move along the length of the staves. In this situation, its impractical to carve these manually therefore the profiles were CNC machined to give perfect repetition of the design.

Next Up - Shaping the Pedestal

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PART II - COMPONENT LAYOUT

Laying out the individual timber components for a new commission is one of the most consequential processes in furniture making, yet it’s treated by some as an afterthought. Well executed, it’s unlikely that anyone will notice. But done poorly, it can undermine months of work and ruin the composition of the piece.

There are competing forces when laying out the components. Economy - how do I get the parts I need with as little wastage as possible, avoiding any knots, shakes, sapwood and other nasties that may show through in the final piece. But timber tone and grain often changes dramatically from one end or side of a board to another. Grain orientation plays a huge role in timber strength, appearance and dimensional stability. The parts also need to be chosen in a way that promotes balance and symmetry in the finished work, as well as ensuring the mechanical properties are maximised.

I think most clients would be astonished to know how long I spend laying out parts. For a 4-board tabletop, there are over 6000 permutations for arrangement of the timber! Some of these rule themselves out quickly (too much change in coloration at the join, too little considerations to cupping), but even once the ABCD order of the boards has been decided, we’re only down to 256 combinations. So here is where I spend a LOT of time. Spinning a board top for bottom, flipping bottom to top, rearrange, rinse, repeat. There’s no such thing as perfect, but I’m finally getting quite good at knowing when the music should stop and the boards have their position.

The same process is true across all types of furniture that I make, the legs of a table, the centre panels of a cabinet. There are always choices and tradeoffs. And if you as a client don’t notice - thats ok - it means i’ve done my job.

Next up - Joinery

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PART I - TIMBER SELECTION

For many craftspeople, a new project starts at the workbench or in the machine shop. For me, it all begins at the timber yard. I’ve never started a client commission without handpicking the timber boards myself and I’m not planning on changing this. A coherent design can be undermined through indiscriminate choice of timber, so it’s just not a risk worth taking.

If you’re buying veneered panels, it’s possible to get near identical colour, tone and pattern throughout an entire project. For solid timber it simply isn’t that straightforward. Solid timber can show huge variations between different boards from the same supplier, even from the same tree. One of the many reasons I don’t use imported timber is that it is often supplied in mixed packs - the timber may come graded to the same thickness, length and width, but the boards themselves can come from different trees, in different forests, in different countries…….

If I’m sourcing for a new commission, I’ll want to be certain that all of the boards come from the same tree. Often this will mean sequential boards as the log is milled, but sometimes I’ll be looking for different characteristics for various components in the build. I may want the components to be quarter sawn - this has both an impact on the dimensional stability of the timber, but also aesthetically (for example medullary rays showing in oak, or lacewood appearance in London plane).

On occasion I’ve taken clients with me to the timber yard - not only a good opportunity to show what the commission may look like at an early stage, but also to gain an insight into the timber that will be coming into their home - where the tree stood, how old it was, why it was felled.

Next up - Laying out Components

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