We are well please with the stand, so here we go with the drum itself… To begin with I spent a good long time umming and arring about the dimensions I wanted, and researching how the different proportions would likely affect the sound. I ended up designing it to be half way between the one used by the York capoeira group (thanks for the measurements Magrao), and some other ones I had seen on the net. Once I had prepared and thicknessed a bunch of suitable ash, and after working the maths, I carefully measured and marked out the staves ready for cutting to shape. The bandsaw table was setup with a 9 degree slope and I actually surprised myself by not cutting a single piece with the wrongly opposite angle.

To work out the correct angle you can use the formula: (360/number of staves)/2. So for example, to make this drum I used 20 individual staves, so I get (360/20)/2 = 9 degrees. If I was doing it again I would consider going for more staves, while this means more of the wood ends up as sawdust and shavings when you are actually cutting out the staves, when the drum shell is complete, it is more round and need less sanding and plaining to take the edges off.

As with the stand, we can roll the shape up easily by arranging the staves thus, and using gaffer tape to hold them together. After a dry run to check everything works, we can add a waterproof glue (I used titebond 3) to the touching edges, roll back up, and use a few band clamps or similar (ratchet straps work ok), to hold it in place.

Once the glue is dry we are left with a nice ash flower.

With half the drum together, we now need to bend in those ‘petals’ to complete the shell of the drum. Before we go ahead and do that, we need to strengthen up the bits we have joined (wood glue doesn’t really like steam) with some metal hoops. I had salvaged some very old strips of flexible steel (which I think came from a long gone bed). With these in hand and my dad’s cheap old arc welder, it was time to get some first hand welding experience.

Not too bad for my first proper weld.

Well ok, so I had a few practice goes on some other scraps. I must say, it wasn’t easy. The metal was relatively thin, so joining them without melting through was a challenge. As you can see, I overlapped them and welded along the top and bottom edges. I think people tend to rivet these hoops, which would probably be easier, but I wanted more welding experience.

Here is the metal hoop in position. As you can see the weld has been ground down a bit to tidy it up.

I really like the way the hoops turned out: as well as being made from reclaimed steel, their bumpy joins and general aged blackness adds a nice bit of authentic ‘handmadeness’ to the drum.

Here it is, hoops hammered on. That done it is ready for steaming.

Drum shell is going into the steam bag. The glue joints are taped to try and help protect them from the steam.

The drum shell is sealed up and the steamer is attached and going. Now we wait... Also, at this point we need to make sure that the bag does not cling tightly to the outside surface of the drum wood. If it does the steam will be unevenly exposed - in the worst cases only one side of a wooden stave will become saturated. This can lead to big problems with warping later on.

It's bending time! Before we get the drum out of the steamer we need everything ready. This is where things can get a bit frenzied because time is ticking as soon as the wood is out of the steamer - it doesn't remain bendy for long. Here we quickly apply a ratchet strap to get the ball rolling.

This stage is not easy and it definitely helps to have a friend at the ready.

Here we are doing are at the final stages of tightening up the drum and bending it. As you can see, lots of different ways of doing it (we tried most of them (mouse over for more).

And then disaster!!!!

The heart sinks as one of the ash staves makes a horrible cracking noise during the last bit of bending.

Mild mannered curiosity at this startling turn of events led to close inspection, which then led me to believe that this slat, dispite being one of my favourite ones for its nice grain pattern and colouring, was a poor choice for bending. It had a very pronounced sloping grain across its thickness. Lesson learned.

Later, when the steam had settled, so to speak, to deal with the crack I welded up another steel hoop and hammered it down over the cracked slat. Here's a close up, with a load of glue piled in there to help secure it in place. As it was the only slat to fail, there wasn't really any structural problems, and afterwards it was possible to make up and apply some wood filler, and sand it all nice and smooth so that it was hardly visible.

In retrospect better technique for the bending, would be to hammer on quite a few rings while tightening ratchets. Particularly round the bend area this would help support the wood. Another thing I would like to experiment with, is curving the original profile of the staves, to decrease the sharpness of the bend when the wood is then bent.

The good news is that the crack didn't go through to the inside, so it should not really affect the sound of the drum.

After all that stressful bending we can treat the drum to a nice relaxing nap with an occasional damp towel down to keep it from drying out too fast on the outside face (compared to the inside) - we don't want uneven drying...

After hand planing the edges off to make the shell more round, and a final fine sand down, we can finish the ash with the same eco-friendly polyx oil stuff we used on the stand.

The drum head is going on. The moment we have been waiting for. We have made four mahogany wedges that are securing a 10mm cross section steel hoop, which in turn tensions up the rope, and the skin.

For the ‘skin’ we are using some more of that reclaimed leather (remember the stuff we used to make the bike grips). It seems to work a treat and goes with the reuse theme of the drum. The rope is 12mm thick, natural Manila.

All the wedges are in, and it is playable!

Here it is with some added rope jazz. Not sure if I am going to keep this yet - I guess it helps protect the shell from knocks and bumps, but don't know about the way it looks.

So that is the drum. At some point I will have to get some clips up of it being used in a roda. Our group was without one before, so it really has added a heartbeat to our capoeira play. Even at home, the drum has an irresistible ‘play-me’ quality, whenever we walk past, it simply has to makes some noise.  Like I mentioned, there are a good number of things I would like to do better next time round – now I just need someone to commission me to make a new one of these beauties…

Posted: 02|14|11 at 12:14 pm. Categorically squeezed into: Woodplay.
Tags: ash wood, atabaque making, Capoeira Atabaque UK, capoeira drum, handmade drum, steam bending, woodwork
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