Tuesday, 22 June 2010


For many years I've wanted an upright bass, even back when I was a lowly drummer (aren't they all?). Now I finally get to build one using plans, tutorials and ideas sourced from the Internet, together with a pile of free wood and some sweat & swearing. it will be a solid bodied, electric upright bass, with a dual piezo bridge and a 'proper' looking headstock. I work to a tight budget (i.e. almost £0) and will hopefully only need to buy tuners and strings, possibly an end-pin if I can't fabricate a good enough one. "Enough talk, where's the damn pictures?", I hear you cry. They're coming soon, I promise ... Nazzy.


I built this scroll & pegbox separately from the neck. This makes it a lot easier to handle and it saves a lot of wasted wood. Also, the scroll & pegbox assembly can be made from a single block of wood, but I used two pieces, one for each half when viewed from the front, as this was the timber I had available. The base of this scroll is deliberately left 'too long' until the end, purely so I can hold it in a vice without risking damage to the carving.

Pinprick transfer of the sketched scroll onto the wood. Yeah it's boring and traditional, but it's completely foolproof. Possibly even damn-fool proof.
Join the tiny dots ... et voilĂ  (or viola, if that's what you're building).
Most of the waste cut away with a hand-saw.
Using a coping-saw to cut around the scroll outline ... (if you have a bandsaw, you'd obviously use it here).
... and you get the 'rough' shape of youir finished scroll.
Another shot of the roughed-out scroll.
Coffee-break brain-training exercise.
Front of the pegbox marked out (using the pinprick method again) and the excess wood cut off.
Using the scrap piece I just cut, under the opposite side of the scroll, to ensure the pilot holes for the tuners are perpendicular to the surface. (I'll be using machined tuners on this build. If you were using tuning 'pegs' the angle of the holes isn't as important).
One side cut to shape, simply mirror the process for the other side.
Front view of the two halves. (I acquired this light/dark wood already glued together, it might result in a nice effect when finished).
Two halves of the scroll & pegbox glued and clamped.
A montage of pictures showing the process of cutting out the scroll. This was done using a Nokogiri (Japanese pull-saw) and a rasp.
To carve the scroll further, some gouges had to be improvised. The blade on this one 'was' a small box-spanner. Another, smaller gouge, was made by grinding an old screwdriver to the shape required.
Some carving done with the gouges and a little sanding.
Outside is channelled using a rasp. The pegbox is cut out too. It's looking almost useable now.
Back view of the scroll.
That's all the rough work done, now it needs a LOT of fine sanding. The bottom will also be trimmed to length and shaped to meet the volute on the neck.

Neck pieces cut out. There is a (possibly unnecessary) 15mm dia. steel rod going inside this relatively short neck. It's over-engineering at its best, but I'm taking no chances with this one.
This is how the neck pieces go together with the monster truss-rod. I will leave the rod sticking out of the neck slightly, to locate and strengthen the joint with the scroll & pegbox.
Taped together neck mock-up.
Neck pieces glued and clamped. Truss rod laid in temporarily, this will be epoxied into the neck later.
Truss rod epoxied into the neck and the truss-rod cover piece (?) glued in ... Initial rough shaping of the neck done.
Clampenstein's Monster: sticking the scroll to the neck ... Mental note: acquire longer clamps.
Unclamped ... pegbox is shaped to meet the neck on the sides & back. Lots of sanding to do now ...

A router jig was made to create the 5½ inch radius for the fingerboard. It consists of a 6'' square, 4' long box with a centre-board that pivots on hinges. A simple 'sled' was made for the router and that slides nicely along the top of the box. The blank fingerboard is cut 'too long' and screwed onto the centre-board at either end. The blank fingerboard can then be moved back & forth under the router-cutter whilst moving the router-sled along the top of the box. This is a ''hands outside the box'' design and ensures you walk away with the same number of digits that you started with.

First run with a 'test-piece' and it seems to work very well.
First run with a 'test-piece', note the wooden dowel handle in the end of the box to swivel the centre-board.
Cut the scrap end off the first test-piece, the radius looks good.
Full length fingerboard blank screwed to the centre board, ready for profiling. I masked the ends where it screws down and coloured them red to enable me to see where NOT to run the router bit, don't want to be hitting a screw with something spinning at those speeds. You'll see the dowel handle has been replaced. It was too wobbly for long-term use and was replaced with an old screwdriver, which doesn't rotate but is much easier to use (proving that simpler is sometimes better).
The jig collects 99.9% (ymmv) of the dust and woodchips from the profiling process. This saves a lot of clean-up time.

A short video-clip of the fingerboard radiusing jig in action.

Fingerboard stained black (1st coat), the ends will be removed later, they are left on to protect the corners of the fingerboard.
The body shape I'm using for this build is copied closely from the Clevinger design with some Photoshop trickery involving pictures of rulers and the Edit>Scale function :-) ... It will consist of 5 pieces: a left/right on the front which are 1'' thick and the same for the back to make a 2'' thick solid body. There will be a 1/2'' wide by 2'' thick 'spine' of lighter wood down the centre of the body, as decoration and to strengthen the joint between left & right sides slightly. This 'spine' will also prove to be an invaluable aid to clamping the body parts successfully.

First two body pieces roughly cut out with a coping saw, I have a template made, awaiting the proper router-bit to ease the process somewhat. This wood is Iroko, a hardwood from tropical Africa that is sometimes called African Teak. It was used as part of the txalaparta, so it should be suitable as a 'tone wood'. lol
'Spine' glued to first piece of the body.
Previous problems solved by clamping the first body piece & spine (red) in the vice with a block against the front of the spine (yellow), and two blocks screwed onto the back of the spine ends (blue). This means I can apply lots of clamping pressure to the second body piece without it sliding around like Torville & Dean on butter.
Third quarter of the body is glued and clamped.
Last quarter of the body is glued and clamped.man, that's been a long time coming.

Back of the body all glued.
Router bits arrived today, let's make some noise.
Front of the body routered to size.
Body fully shaped and rounded-over. This thing weighs a ton.

Neck-pocket template ready for action.
Neck pocket almost finished, just need to square off the corners with a chisel.

First mock-up just so get a proper idea of the size of this beastie.
... to be continued.

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