Thread: table top design - short lengths of wood

End to end joining is actually quite common. I have eaten at a table that was made from offcuts joined end to end and the food tasted OK

One way of doing it is with a finger joint - you see this a lot in timber building materials such as fascia board. It's recognisable by the zig zag profile of the join. You can get router bits to make this joint but they are a bit expensive and tricky to set up.

You could do it with some sort of scarf or splice joint.

If you make sure to stagger the joins, it will be OK.

You would have to be careful as the joining of so many boards across the grain & the affects of moisture your table might ''grow'' in length with a bit of humidity.
You might get away with using buttons on the sides only.

Hmm, I didn't read your post properly.

As far as I know, there is no reason you can't have the grain running the width instead of the length. My friends have a dining table made from American Oak with the grain running that way. The 'wider' the cross grain, the more seasonal movement you will get at the ends, so you can probably expect it to expand and contract a bit more than if oriented the other way. You'd need to make sure your top is allowed to 'float' on the frame by using slotted screw holes, buttons or some other flexible fixing arrangement.

You could go for a traditional Arts and Crafts style of table which has breadboard joints at the end and in the middle so that most of the grain is still running along the length of the table but you don't need end-to-end joints (see pic)? For tidyness this style needs long pieces for either side but the rest of the top can be made of quite short pieces.

Construction of this style of table is of necessity quite tricky due to having to allow for differential expansion of grains running at right angles - but there are heaps of plans for this kind of thing available so you shouldn't have to reinvent the wheel.

Steph

this is great - just what I needed. I'll start researching further on seasonal/humidity movement. Also on using buttons (I remember seeing them referenced somewhere) and whatever other ways to counteract the movement.

cheers

Mick

Steph,

thanks for that idea as well. Apart from it helping with movement, I like the design as well.

Mick

No idea where I saw it, but I saw a table with the top made out of 30x19 tas oak. The strips were going accross the table with the 19mm edge showing making the table top 30mm thick. Lots of glueing involved and as previously mentioned, seasonal movement is an issue but it created quite a dramatic effect with the subtle differences in the tone of the wood from strip to strip.

Corbs

Originally Posted by mick59wests

Hi,

every table top I've seen that joins lengths of wood together has the lengths of wood equal to the length of the table as opposed to the width eg: if a table is 1200 x 800, you use lengths of wood 1200 long and join enough of them to make it 800 wide.

Mick - you haven't looked at enough tables! There are zillions of tables with the boards running crosswise. This is always the case with tables made to take extra leaves, for example. There are no particular problems with this construction, just make sure the top is secured by buttons or other means which allow a bit of seasonal movement. In theory, the whole top should expand and contract evenly, but in practice, most of the movement occurs at the ends, so overall movement is not as great as you would calculate. However there WILL be more total movement with this method than if you had long boards running lengthwise.
Cheers,

We had a very nice table in our shop recently with the boards running across the table width rather than down the length. It was cedar and the boards were about 300mm wide and 900mm long, five boards in all. So the table was 1500x900. Very handsome table, lots of interest in it.

I'm never sure what to use for moisture content with these things, but this calculator, using initial moisture content of 8% and final moisture content of 15% has the table changing in length (tangential movement, assuming plainsawn boards) by about 25 mm.

Originally Posted by zenwood

I'm never sure what to use for moisture content with these things, but this calculator, using initial moisture content of 8% and final moisture content of 15% has the table changing in length (tangential movement, assuming plainsawn boards) by about 25 mm.

Yes Zen, as I said in my post, the theoretical movement is a bit horrifying, but in practice it doesn't seem to move anywhere near that much, certainly not on the several tables I've done with boards running crosswise. A large walnut table I made had fixed leaves more than 1500mm wide (long??) & moved hardly at all in the time it was in my possession, which was about 15 years and included some moves between pretty extreme climates in two countries. I was expecting to see at least 20mm or so movement taking it from a climate where heating for 5 months of the year was the norm, to a climate where 80% plus RH for half the year was the go, but any movement was barely perceptible on the fixed end, though there could have been more in the overhang ends. The wood was probably around 10% MC when the table was constructed.

But - still allow for movement!

Cheers,

I think it would also depend upon the finish used, yes?

Originally Posted by silentC

I think it would also depend upon the finish used, yes?

Silent - the finish will certainly slow down moisture exchange, but never stops it, according to all the good books, so over the course of a year any wood will go through a fair range of MC in a climate like Brisbane's, for e.g. (That's if it ever decides to rain like it uster, ever again! )
Cheers,

Our family room table has the grain running across. It is an extension table 1000x1800 opening out to 2400. Top is made up of pieces approx 90x35mm glued together. Looks OK and no problems with top but as it is in three parts (incl fold out extension) that probably helps.