Building Bass no. 5

  This was really fun. Many thanks for help with the CNC to our friendly neighbours who design beautiful furniture. http://www.staffanholm.com/  There are spacers at all the blocks and bouts. They are attached securely with Rampa muffs.

Here are some pictures of the neck attachment. It's a little bit like the tightening mechanism on a bow. The neck will sit on top of the walnut and the brass piece where the bolt goes will be shorter. And of course the neck block will be shaped, losing a lot of the side material. I'm working parallel on fixing a C-extension at the moment so it's going a bit slow.

I planned out side view of the bass to look at the neck angle see how everything works together. You can see how nice and efficiently the C bouts make space for the bow when you compare the side view to the front plan. Also the point where the octave is on the strings is marked and it compares nicely to the curve of the ribs there, so the upper bouts shouldn't get in the way, rather provide a comfortable reference point for thumb position. Next I compared the size of the bass to other instruments. It's about as much smaller than the Amati bass as it is larger than the little Maggini Delmas. It is slightly smaller than the bass that I made for Magnus. I've also been working on neck fitting bits, but waiting for a better photo opportunity.

 I got the inner and outer templates cut today and the inner forms for the ribs. There are some more parts for which I'll have to wait until Wednesday. It was quite a thing to see the digital plans materialising in real life - 16th century design, 21st century technology. They came out really nicely. I will probably make another f-hole template by hand as I want to make some small adjustments. It's good to have the theoretical placement in the template. I also worked a bit more on the neck block and fitting.

Not a great deal to show today. Lots of thinking and preparations. I starting working on the neck fastening. It will bolt into the little piece of brass which will be able to be moved back and forth. There'll be carbon fibre reinforcements and all the metal will be able to be removed with a simple operation and more traditional neck fitted if one should want to do that in the future. I like that this neck will sit on top of the bass like the original necks of these old instruments. I'm going to cap the fitting with ebonised walnut. I think that will look nice.

 This scroll and pegbox is a really lovely shape. I had used the scroll before but with an elongated pegbox, to make more space. I didn't realise until now how elongating the pegbox disrupted the harmony of the lines.  When shaping the cheeks I pinched them in a bit at the top and then let them flare out slightly lower down. It's subtle but it gives a more dynamic, alive feel. The photo taken from the front shows this, but in an exaggerated way because of the camera angle. In real life it is quite pleasing.

Got a bit further on the pegbox. It's a rather thankless and time consuming job, so nice to get it out the way. I'm quite happy with lines and how clean it's looking so far. It's quite small and therefore extra important that there's enough space for the string to go around the top tuner.

 I'm doing a comparison of 4 different fingerboards with 3 different playing set-ups. It will be like an article and it is not finished yet. But I did discover something interesting.  When setting up a new bridge, I've noticed that even when everything is perfectly centred, When you look from the front, it's like the strings are more to the bass side. I assumed that this is because of the thickness of the strings, and I normally compensate for it by marking the string centres on the bridge slightly more to the treble side.  However, there is another reason, and this is because of the way the strings get progressively further from the fingerboard, while staying the same distance apart. It's like they are unfurling and that makes them stretch out towards the bass side as they "unfurl". It's kind of obvious when you think about it. I just hadn't thought about it in that way before.

 Here is how the bass bar is looking  And the inside of the pegbox, so far. Then we took newly baked hot cross buns to a picnic concert in the anemone woods down the road from the workshop. A very special portable acoustic piano. It was very lovely.

I bent and glued the last strips for the bass bar. I also started to hollow out the pegbox bit got called away before I could document. Will carry on tomorrow.  

Today I had to do some bow repairing but I still managed to do the center line on the scroll and bent the spruce strips for the bass bar and glued the first ones together. I used hide glue, one joint at a time which I have come to prefer over titebond or epoxy, for this job. I will glue the other two strips tomorrow.  

 Today I planed the neck square so that I could saw it out on the band saw. I did the final shaping by hand. I really like this pattern and hope that I can do it justice. It's taken from a 1695 Ruggieri.

 I spent a the weekend deep diving into the fingerboard geometry, and tried a variety of different things - different radiuses and how they would work for different sets of strings, to figure out what would be the best profile for the specifications: 1040mm string length, fingerboard width 40 - 90mm, strings 26mm apart. 5     5.75     6.5     7.25 string height from fingerboard at 92 cm which should give the notes G, G sharp and even F. When a ruler is placed across the middle two strings, there should be 9 mm distance from the ruler to the outer strings to give good clearance. In order to get this I dropped the outer two strings half a mm, keeping the distance of 26mm. Making the radius smaller did not help. Instead I flattened the profile out under the outer two strings which will make for a lighter fingerboard that should be possible to be made in one pressing instead of two. This is what the profile looks like. I haven't finished the surface modell...

 I spent the day finishing the wood for the blocks and sawing and planing the 6 strips each 4mm thick that will be used to make the "cosmic" bass bar.  It was a good work out. I won't be able to CNC the inner form until after easter, so next week I'll probably start work on the neck, pegbox and scroll. I'll do some more work on the fingerboard this weekend. I want to see how it works with the strings.

 I spent the morning working on a new CAD model for a lighter fingerboard. It will be a little narrower than the standard model, the radius flattens out underneath the outer strings, and it is less high. I would like there to be a bigger ratio of neck to fingerboard for a relatively thinner neck. Hopefully it will be able to be made with just one pressing rather than two layers glued together. It will also be extra long. And the afternoon preparing blocks and linings.

 First thing this morning I checked the back joint and it's looking very good. It's so pretty here where the grain turns inwards and meets in a point, it's a bit sad to have to cut it away. After this we went to Alingsås for a delicious morning 'fika' with the breakfast club at Peter's workshop. We admired the 18th century Scottish clock that Olof had restored and had a look at the latest projects in the woodwork shop. Peter had a magnificent piece of flamed ash that I ended up buying. It's big enough for an octobass or 2 or 3 flatbacks, if we can get it sawed right. It was incredibly heavy and difficult to manage so we cut it in two. The afternoon I spent working on the digital files for the bass form that I'm hoping to be able to CNC.    

 The grain of the flamed ash is very beautiful along the gluing line. It's a shame that it will be completely hidden in the end. When I check the flatness of the surface I use a 50cm hairline ruler. I walk it gently back and forth over the surface and where it wants to pivot, there is a high spot. The long sharp plane removes these high spots easily. I made the same rubbed glue joint with the ash. Tomorrow we will see how it went.

 The plane was very sharp, the work went quickly and I was very happy with the joint. I used fresh hide glue and a rubbing joint with just two light clamps. 

 All three ribs are now thinned to 2mm. At this point the stiffness disappears and they start to feel alive. It's more work to do them by hand but you do get a better feeling for the wood. We've had lovely sunny weather so I took them outside for the little photoshoot

  Another day of planing rib material. 2 down, one to go. We like to spray water on the plane shavings and watch them come alive.

One face and one long edge of each wood panel has been planed to 90 degrees. I trimmed some of the excess and let it rest for a while in case there was any hidden tension in the wood there. Today I started preparing rib material with my Stanley plane and a toothed plane blade. I managed to thin one of the 3 rib pieces from 4mm down to 2mm. One side, which will be the outside, I spend extra time scraping so that it has a good finish.