A Tale of Two Tables: 6. Spit and Polish

Here begins the final post in the table saga. It has been a long time coming - the project has taken 18 months from conception to completion but it is done. The observant amongst you will notice that these photos are all of the large table - the small table was finished in the gloom of the evenings. Enough waffle, onto the details! 

We liberally applied a belt sander to take out the slight ridges left after biscuit jointing the top. In a heatwave this was warm work. My hands were turned black with a combination of oak dust and sweat! To get a super smooth finish on the top we then ran over it all with a random orbital sander and 180 then 240 grit paper. 

One smooth, dusty table top.

To get the finish we wanted required several finished, all of which could have been used in their own right. The frame was also a slightly different finish from the top - just to keep things complicated (actually for different wear characteristics but I shall come to that). For the top and frame we applied two coats of Danish oil to bring out the grain somewhat and accelerate the ageing. It should continue to age and mellow further but we are impatient and didn't want to wait 30 years.

Coat two of Danish oil goes on.

The Danish oil will protect the wood to a certain extent but we wanted a very durable surface for the top, one that will stand up to the abuses of many years. There will be many who will gasp when I say what we did next but it should allow us to use and love the table rather than handle it with kid gloves. We basted the top in waterproof gloss varnish. Heinous crime as that is, it provides the waterproof barrier to allow us to not worry when someone spills a glass of wine over it. But it isn't a nice finish. In order to take a final finish of beeswax (which we also applied to the frame) we used wire wool to take the top down to a matt finish. This should allow us to know when we need to add more beeswax as the table will become matt. There is something rather odd about sanding down a layer of finish!

Wire wool applied with the mounds of dust to clean.

The beeswax layer came next to bring it up to its full shine. This was a most rewarding layer to add!

Jenny applies the finishing touches to the polish.

One finished top.

For those of you who didn't see it earlier - this is what the finish does to spilt water. Nicely repellent.

Water pooling on the table top.

With the top and frame finished the final job of joining the two remained. This is an important stage to plan - as I mentioned in the first table post the wood will keep moving, for many years to come. If the top is simply screwed to the frame it will probably warp and crack. It needs to be able to expand and contract, notably across the grain (the width of our table). There are many methods of attaching a top to allow this, primarily falling either into a category of a widened screw hole or a lip / grove combination on the fitting. 

I decided to take a simplified approach to the traditional tongued block and groove on the frame by using a half glued biscuit joint. I glued the biscuit into blocks and put matching groves in the frame. In the middle of the width a block is screwed to the frame and attached to the top with a single screw to provide a center for expansion / contraction. 

Everything was piloted and countersunk at this point as driving screws into oak is not an easy thing to do. This is exacerbated by the fact I have used brass screws to prevent it reacting with the oak over time. These are not as strong as steel screws and are also slot heads rather than plus or posi, giving a poorer grip and greater liability to get graunched. Steel and oak react over time, producing a black iron oxide. This then gets worse with atmospheric sulphur by producing sulphuric acid! Not great in a table that I would like to outlive me. Hence brass screws.

Cutting the blocks.

Block sat beside its groove awaiting fitting.

Blocks being fitted. Note the smaller screw block in the center.

 And finally, a finished table!

Finished table.

Christening the table.

Previously: 5. It's got legs

Or read the whole series from the beginning: 1. Grand Designs

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A Tale of Two Tables: 5. It's Got Legs

A solid base is key to the functionality of any table. A lovely top will be ruined by an uneven, twisted base or one with legs in the wrong place. For our small table we went for four legs in a square, 20" apart leaving an 8" overhang outside the frame. Traditionally the cross pieces would be mortice and tenon joined into the legs. This is a fiddly process but if done right is immensely strong. We do not poses the skill of years of practice at mortice and tenon joints so ours would neither be accurate nor straight! I am very grateful however for the research of John D Wagner who showed that biscuit joints can be stronger than mortice and tenon or other methods. Although the research was limited it provides some armour to fight those traditionalists who think biscuits are no use in structural elements.

Enough design - onto the doing. As we were biscuit jointing all we needed were square legs and straight ends to the cross pieces. As the legs were already square that left us with cutting the cross pieces to length in a square manner. This was another job for the router to try and get the ends square and allow millimetre precision. If you had a decent table saw you may be able to use it instead but there are only a few power tools in our garage!

Having cut the ends we then used a curved bit for the router to round the underside of the bar. The biscuit jointer then came out again to put the slot in for the biscuits. We aligned this slightly off centre to ensure the biscuit didn't show at the bottom (I am sure this probably sacrifices a little strength but it only came out the top a fraction).

With the frame cut, rounded and slotted the attention shifted to the legs. We needed to choose the outside faces, check for any cracks or deformities where the biscuits would need to sit and mark which end to remove the waste from (in a straight manner). Lacking a power saw this was a time for hand tools. The router would not have the depth to cut this one. I used a tenon saw for better control of the cut, the 2 1/2" legs just fitting on the blade. 

To ensure the legs were all absolutely even we strapped them all together with a large quantity of elastic bands (many of which we snapped in the process) and sanded the ends flush. Two slots per leg later we were ready to sand all the parts of the frame and glue it.

To assemble we glued the legs into pairs, let that dry enough to hold itself, and then brought the whole frame together. A webbing clamp held it all together and we used the sash clamp on the diagonal to apply very slight pressure to pull it all square.

Previously: 4. Starting at the Top
Next: 6. Spit and Polish

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A Tale of Two Tables: 4. Starting at the Top

Constructing the table top is a simple theory. Stick several wide planks together. Our table top is based on seven 6" planks, being cut to a square once joined. Rather than just butt the planks up against each other we wanted to join them with a stronger joint. To get a stronger joint you need a larger surface area of the planks in contact with each other. Traditionally that would mean tongue and grove, dovetail or something similar but these methods all require careful joinery with expensive router bits. With 24' of join to make I didn't fancy attempting dovetails! Conveniently there is a modern alternative that provides a reliable joint almost as strong as a well made traditional joint - a biscuit joint.

A biscuit joint is made with a pointed oval biscuit of compressed beech that fits into a cut slot on either side. This reinforces the joint be adding glued surfaces deeper into the join. A biscuit jointer cuts a 4mm high curved slot and is precise, repeatable and fast. A specialist bit of kit but very handy for all manner of things (as you will discover as the project progresses).

Before we even started cutting we laid out all our planks and clamped them to allow us to mark up the square, align the planks and position the biscuits. The outside two planks had alternate double biscuits to add extra strength where it overhangs the frame. all the others had single biscuits.

Having cut all the joints we did a dry run, slotting it all together with biscuits. Fortunately the biscuits resolved the slight bowing that a few of the planks were showing. When clamped it all fitted together well (clamps on alternate sides to prevent curving the top). From here it was time to glue. We took care to glue all the surfaces that would be in contact, including the biscuits. The glueing was also done in stages, few planks at a time and then letting it dry for a while. This was because even with three of us gluing we wouldn't manage to get everything glued and together before it had started to set - the weather was against us!

 To try and ensure a good pressure across the length of the table we used a ratchet strap to hold the centre of the table once it had been clamped, allowing us to move the clamps nearer the end. Note all the blocks of scrap wood to prevent the clamps damaging the surface.

Once dried we then clamped up the ends for cutting. A stress relief cut was made with the router to a depth of 8mm on the reverse, 1cm behind the final edge. This was to ensure the waste wood didn't splinter off with the table top. When cut from the top to a depth of 18-20mm from the top surface the ends gently cracked off, allowing easy trimming of the remaining waste wood. A block of scrap wood was clamped to the outside to try and prevent the edge being splintered by the router. Once cut it was ready for finishing but that is for another post!

Previously: 3. A Twist in the Tale

Next: 5. It's Got Legs.

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A Tale of Two Tables: 3. A Twist in the Tale

Wood is a living thing. Even after it has been felled, dried, and cut it will continue to move. It will expand and contract, crack and generally warp. This is particularly noticeable across the grain on wider planks. Subsequently the attachment of the table top is designed to allow the whole sheet to expand and contract. All the best laid plans however can be thrown by the timber.

Many of our planks have knots in them. The dark swirls add interest to the pattern of the grain and can be a delightful feature of the wood. They are however a pain to work as they are tougher than the surrounding wood.

We got our planks planed and thicknessed by the timber yard as the equipment to do so is beyond the means of most amateur wood workers. When we started to try and clamp the table top together we discovered that one plank was not square. It appeared to have hit a knot when having the edges planed and twisted slightly (you can see the gap between the square and the wood in the top photograph). This wasn't the wood moving for the top remained flat. We therefore had to re-straighten the edges. Without the proper machinery the most accurate we could do was use a router to re-cut the 90 degree edge. Several sessions of carefully measuring, clamping a guide, cutting into the edge of the wood millimetre at a time and remeasuring later we had a square plank again.

Previously: 2. The Hills are Alive with the Sound of Chainsaws

Next: 4. Starting at the Top

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A Tale of Two Tables: 2. The Hills Are Alive With the Sound of Chainsaws

I like wood. It may be strange to some, but those who have worked with it will understand. It is a tactile, sensory thing. Some woods assault the nasal passages with their rich oils whilst others caress the skin with their smooth planed surfaces. Some give to the slightest cut whilst others are strong as steel. They can be as pale as snow or brightly coloured like an autumn sky. Grain can provide majestically sweeping flow to surfaces or interrupt the eye like bright stars in the sky. All in all the choice of wood for the table was going to be pretty important for me.

Aesthetics aside I wanted a native wood, one that wasn't costing the earth but was supporting proper forestry. Practically I wanted something tough enough to survive the abuses of family life and come out with character not flaws. Realistically this limited my options a little! To get the durability I desired I would need to look at hardwood species. This narrowed me down to perhaps a dozen options, which I then narrowed down further based on the strength of the wood. There are lots of papers and books discussing and comparing the toughness but I shall leave those for you to find.

This left me with a choice of oak or cherry. We decided on oak for the extra fraction of toughness (as lovely as cherry is). I managed to find a local timber yard who specialised in regionally sourced woods that were based in Wentwood Forest near our home. This forest is being actively managed and slowly turned back into traditional deciduous woodland. The oak isn't quite ready yet so ours came from Powis Castle, 90 miles away. Wentwood Timber were very helpful, cutting and planing all my planks for me. All the photos on this page were taken on their site one sunny April afternoon.

Finally: one car full of oak for the tables.

Previously: 1. Grand Designs

Next: 3. A Twist in the Tale

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A Tale of Two Tables: 1. Grand Designs

There has been a large rectangular hole in our home ever since we got married. Our first flat was unfurnished so we begged, borrowed and freecycled the furniture we needed. The table is the only piece of furniture left that is on loan. More than a year ago we decided to start planning and, several design iterations and a house move later, construction is now under way. The biggest challenge to be faced in the design was meeting our own requirements! We want something that will suit the two of us eating breakfast, and something that will sit all our immediate family for an extravagant Christmas dinner. That meant an expanding table.

I should warn you now this post is long and features lots of numbers and theory - just wait for the later ones if you would like pictures!

Both of us had come from family homes with tables that could expand to some extent or another. Jenny's parents table slid apart and clipped an extra leaf in. My parents had an unusual antique design that expanded / contracted with a threaded rod up the centre of the table (like this one). The threaded rod meant it could properly clamp down on the extra leaves and expand a large amount without sacrificing too much strength. This is important but I shall come back to it later.

The first thing to do was work out table sizes. Based on our design criteria we decided we needed to sit 6 comfortably, 10 expanded but should be able to squeeze 12. This is where it is time to crack out some maths. We assumed that we would sit one person at the head / tail of the table and the rest along the side. Assuming the table is somewhere between 3 and 4 feet ( ' = feet, " = inches for those new to old units) wide the lengths are relatively simple. Allow 12" from each end for the end sittings. Along the sides each place needs 24 - 30 " for a generous sitting. We measured and decided that 24" seemed ample for us - our dinner setting with room either side fitted easily. This meant we needed a 6' table that could expand to around 10'. The width was an easier matter of measuring how far we could comfortable reach to pick up a plate from over a table. We settled on 42" (3'6" - for some reason table widths are normally defined in inches) as being big enough to get plenty of dishes in the middle but small enough to clear both sides at once.

Asking a table to stretch that far requires some careful consideration of the physics. There are three main methods of expanding a table, all boiling down to the frame beneath.

1. Keep the legs in the same location and extend the overhang of the top.
2. Stretch the frame and keep the legs at the corners of the table (inset or otherwise).
3. Add extra legs to support an extended top.

These designs have some limitations for us. The first is typically limited to an extension of 24" or so (like this)- otherwise even with additional frame beneath you gain too large an overhang. This is a problem because people tend to lean on tables, even push against them when standing up. Imagine your largest friend (don't name them, just imagine them) pushing on a table top with a two foot overhang. Its going to need a lot of support! With normal table top thickness (3/4" to 1 1/2") an overhang of up to 12" is workable. This method isn't going to manage our 4' extension!

The second design allows a slightly larger extension than the first but still struggles with enough strength for large extensions. The frame needs to overlap sufficiently to still provide strength in the centre of the table when extended. This can be done - my parents table (mentioned earlier) manages it by using a threaded rod to clamp the two halves together. This keeps everything more rigid and stops it twisting, reducing the load on the centre of the frame when loaded. Still hard work on the wood and perhaps worth seating your largest friends nearer the legs (in the nicest possible way).

The third method does allow a large extension - almost any size imaginable but adds extra legs and is often done with drop leaf tables, blocking leg room when in the reduced size configuration.

Owing to the cumbersome nature of the drop leaves we decided to try and plan a table based on the second design. I found suppliers for a coarse threaded rod and worked out the combination of bolts to allow one end to rotate but not move and the other end to slide up and down the bar. Then we bought a house. This is the quickest way I have found yet to derail a project! By the time we got back round to the table it was winter and our loaned table was in the corner of the kitchen rather than the conservatory where it had been all summer. We had accepted this when we got the house and decided we would build our grand table in the conservatory and abandon it each winter for a second hand table that we would find for the kitchen. Then we realised we could kill two birds with one stone and settled upon our final plan - a variation of the add extra legs design.

We decided to build two tables. Both the same width, one 6' long and one square that when placed at the end of the other would extend it to our magical requirement of seating 10 people. A kitchen table and a dining table, which can be brought together to make a banqueting table.

The positioning of legs still required a little work - in order to be able to sit the full number comfortably when the two tables were together and not have someone banging their knees. We decided to make sure the two tables had a combined overhang at the head that when joined a person could sit exactly between the legs on the join. This would then leave two people between the legs on the larger table and one on the smaller (on one side, plus the head and tail of the table giving 10 total). From here on the design is relatively straight forwards. Build a top from planks joined together, make a box shaped frame underneath (with additional supports on the larger table) and join it all together in unison. Plan sorted! I will give the details at each stage of the build in later posts.

Next in the series 2.The hills are alive with the sound of chainsaws 

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