Tag: 5-string double bass

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Beginning the Plates

Beginning the Plates

Bookmatching the Plates

When I last posted, I had the garland pretty much complete, and the materials were prepared for the neck and the front and back plates.  I had cut the back plate roughly to shape, in order to use as much of the “fall-off” material from the back plates, as possible, from which to make the neck.

I went ahead with the neck and scroll, just because I find it encouraging to have some of the “pretty” work done, as it makes me feel that I am making progress. You can see the neck progress, here.

But at some point, one has to go ahead with the task of bookmatching the plates and getting them ready to carve.

Sitka Spruce front plate halves for the five-string double bass.
Sitka Spruce front plate halves for the five-string double bass.
Rough shape of five-string double bass back plate, and template for the neck.
Rough shape of the five-string double bass back plate, with the template for the neck. The neck was cut out of the scrap from the back.

 

So, for the front and back plates, the next thing on the agenda was to plane the center-joints absolutely flat and straight and then glue them together. It took two tries on each of them, as it turned out that while they were technically “straight”, and if I put a try-square at any given point, they seemed to be square…in reality, there was a longitudinal twist to the surface I had planed, and the fit was not acceptable. (sigh…) No big deal… I just had to saw the joint back apart, and try again.

Finally, I got everything lined up correctly; then I glued and clamped the plate halves together, and produced the plate banks, ready to trace the actual shapes.

Sitka spruce front plate for five-string double bass, bookmatched and ready to glue.
Sitka spruce front plate for five-string double bass, bookmatched, and ready to glue.

 

Front and back plates for five-string double bass, bookmatched and ready to trace shapes.
Front and back plates, bookmatched, and ready to trace shapes.

Tracing the plates

Sitka spruce front plate for five-string double bass, ready to trace the shape.
Sitka spruce front plate, ready to trace the shape.

 

Ready to trace the shape of the front plate of the five-string double bass.
Ready to trace the shape of the garland onto the front plate.

 

Using a pipe spacer to trace the shape of the five-string double bass front plate.
Using a pipe spacer to trace the shape of the garland onto the Front plate.

 

Tracing the plate out with a pipe spacer like that enables me to establish a very even overhang of about 4.5 mm. The problem is, it also makes round corners, which I did not want. So I had to correct, the corners, using a long straightedge to “point” the corners toward the center of the plate at the far end, and then use circle templates to extend the curvature of the plate edge above and below the corner to meet the straight lines. (Incidentally, the reason I have stopped using a washer for a spacer, is that any washer small enough to have the right distance from outside to inside also is so thin that if there is the smallest change in the fit between the plate and the garland, the washer will slide under the garland, changing the overhang distance to zero. The thin slice of PVC pipe never does that.)

Cutting out the Front Plate

I used an old Craftsman “Auto-scroller” saber-saw (Hand-held jigsaw) to cut out the perimeter of the front plate. Ann, my beloved wife, bought me that saw 36 years ago, when we had been married for only about three years. That little saw has a lot of miles on it!

Cutting out the completed shape of the front plate for the five-string double bass.
Cutting out the completed shape of the front plate. I am not attempting to cut exactly to the lines. I will correct to the lines, after the arching has been completed.

 

Cutting is complete: the front plate for the five-string double bass is ready for arching.
Inside view: the cutting is complete: the front plate is ready for arching.

 

Outside view of the front plate for the 5-string double bass.
Outside view of the front plate.

Arching is Next:

Before I could begin arching, I needed to mark the intended plate thickness: I used a marking tool to scribe a line all the way around the plate at 6 mm. Before the plate is done, this will be reduced to 5 mm in most areas. I used a ballpoint pen to highlight the groove so that I could more easily see it when I am working, and not accidentally go past it.

Edge-thickness scribed into front plate for the 5-string double bass.
Edge-thickness scribed into front plate.

 

Then I secured the plate in a cradle especially made to fit this design, and secured it in place by affixing small squares of 1/4″ plywood around the perimeter so that the plate will not shift laterally, while I am working on it. The reason the little stop-blocks are so thin is that I do not want them to be in the way when I am planing the edges.

Front plate for the 5-string double bass secured in a work cradle.
Front plate secured in a work cradle.

 

Tools for arching the five-string double bass.
Tools for arching: cradle, gouges and planes.

 

Sculpting the front plate arch for a five-string double bass.
Sculpting the front plate arch.

 

five string double bass arching in progress.
Front plate arching in progress!

 

Planing the arching surface smooth on a 5-string double bass.
Planing the arching surface smooth.

 

Planes used to shape the 5-string double bass.
Some of the planes used to shape the bass.

 

Shadow line defining the longitudinal arching shape of the 5-string double bass.
Shadow line defining the longitudinal arching shape.

 

Transverse arching shape of the 5-string double bass.
Transverse arching shape.

 

Arching for the 5-string double bass nearing completion.
Arching nearing completion.

 

Arching and outline completed for the 5-string double bass.
Arching and outline completed.

 

Time to lay out the F-holes!

F-holes laid out for 5-string double bass.
F-holes laid out, incised, and inked.

When I build the smaller instruments, I inside the f-hole perimeters quite deeply, knowing that, without exception, I end up needing to correct the arching, using the f-hole side-profile as a guide. I want the “stem” portion of the f-holes to be essentially parallel to the plane of the garland-plate joint when viewed from the side. On the violins and violas I have built, I have universally found that, in spite of my best intentions, I have left too much “puffiness” in the area of the lower wings of the f-holes and I need to plane away more wood. If I have incised them deeply enough, I don’t lose the marks when I remove the wood.

I was quite pleased to find that, on this instrument, the side profile was exactly what I had hoped for, as soon as I laid it out.  So I incised them, but not very deeply, and then inked them with a ball-point pen, so that I could easily see them while perfecting the arching later, using a scraper.

So– the next step will be to complete the “graduation” of the plate– carving away the majority of the wood thickness from the inside of the plate, so that the plate is the correct thickness all over…ranging from 9mm at the center, all the way down to 5mm in the flanks.

Ready to carve the front plate graduations of the five-string double bass.
Ready to carve the front plate graduations.

But…I will leave that post for another day.

Thanks for looking.

 

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Back to the Bass!

New Project? Nope! Not really!

Picking up where I left off:

This is not really a new project, but rather one that was “tabled,” for lack of better term…work was suspended until a better set of circumstances emerged.

I built the mold for this bass in 2015, began bending ribs in 2017, with a woefully inadequate bending iron, and a great deal of frustration.

A commission came in, so I set aside the bass, to work on the cello, and never came back to it…so it sat in the corner of my workshop silently sneering at me every time I looked that way.

But! Since I was laid off from my job, where I had worked for 33-1/3 years, in January, I am catching up with some projects and able to face others with new eyes.

Here is the five-string 16-1/2″ viola I am just finishing up, balanced on top of the bass mold:

Large viola with five-string double bass mold.
Large viola with double bass mold.

Once I had the bass mold up on my bench again, it was easier to confront the problems, rather than avoiding them.

 

The New Bending Iron

The first thing I needed was a new bending iron. A fellow I met online, John Koehler, a fellow bass maker, told me how he built his bending iron. So I followed his lead, and built a new bending iron:

Homemade bending iron, enabling me to bend the ribs for the 5-string double bass.
My homemade bending iron.

 

It is a section of exhaust tube, welded to a piece of angle iron, so that I could clamp the apparatus in a vise. Heat is supplied by a 550-W electric charcoal briquette lighter, controlled by a 600-W dimmer switch. It took a little trial and error to get it set up correctly and to calibrate it, but it turned out to work very well! (What a relief!)

Bending the ribs

Bending the remaining two Big Leaf Maple ribs was nearly effortless, and took about ten minutes, tops, not counting waiting for the tube to heat up.

Lower ribs bent to approximate the mold shape of the 5-string double bass.
Lower ribs bent to approximate the mold shape.

 

Installing the ribs and linings

Then I glued the ribs into the fir blocks on the mold with hot hide glue, one at a time, and affixed the willow linings in the same manner before moving to the next rib.

Treble rib with linings installed on the 5-string double bass.
Treble rib with linings installed.

 

Once one rib was completely secure, trimmed and lined, I rolled the bass mold over and repeated the operation on the other side.

Bass side rib with linings installed on the 5-string double bass.
Bass side rib with linings installed.

 

I planed the linings flush with the ribs and blocks, and the garland was essentially complete. It will require careful leveling before fitting the plates, but not much other than that.

Completed rib garland for the 5-string double bass.
Completed rib garland.

In the coming weeks, I will complete the center-joins of front and back plates,  then complete the carving of the plates and the neck and scroll, and start putting this bass together!

Just as a teaser, this is the wood for the front, back and neck:

Sitka Spruce billet for the front plate of the 5-string double bass.
Sitka Spruce billet for the front plate.

 

Big Leaf Maple for back plate and neck of the 5-string double bass.
Big Leaf Maple for the back plate and neck.

(Notice that there is a fair chunk left over where the neck pattern does not use all the wood it is on: watch that space! )

Thanks for looking!

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Five String Instruments

Five-String Fiddles

I get a fair amount of demand for five-string fiddles; in my case, that means a five-string instrument with the same footprint and scale-length as a violin, but with the added C-string, so that it carries the full range of both a violin and a viola. I have mastered this genre to the point that the low end of my five-string fiddles sound like a good, small viola, and the high end sounds like a good violin…and the neck width is just barely wider than that of a violin (25 mm) so that it plays like a violin.

Teachers like them, because they can teach the viola part or the violin part, without having to change instruments.

Wood Selection

One of the beauties of a five-string fiddle is that, because it is non-traditional, I am not under the burden of using traditional woods, so I am free to experiment, and, as it turns out, there are other woods that work quite well: I have made them of domestic woods; Big Leaf Maple/Sitka Spruce (or Englemann Spruce), but I have also used Koa/Sitka Spruce, Myrtle/Port Orford Cedar, and all these combinations worked quite well. I will soon try a five-string fiddle of Bubinga and Sitka Spruce and am open to other experiments.
I will continue to build and sell five-string fiddles either on speculation or on commission, as the demand increases.

Five-String Violas

I am beginning to hear a call for Five-String Violas as well. These have the same range of pitch as a five-string fiddle, but the physical instruments are whatever size viola is preferred by the customer. Though I have already built several sizes, until I get an increased demand, these will likely remain as custom commissions, not just built on speculation, such as how I currently produce the five-string fiddles.
The practical difference, then, between a five-string fiddle and a five-string viola, is that the (usually larger) five-string viola will usually have deeper, richer, louder tone, just because it has a larger resonating body, both of air and wood. But not everyone can comfortably play a larger instrument, so this is a matter of personal choice.

Five-String Cellos

Five-string cellos are not a new thing. The cello-piccolo and the cello da spalla have been extant for centuries, and music has been specially written for both. I hope to see a rising demand for these instruments, but, for the moment, they are a rarity. I can build both, and hope to soon have some to display here, but, for the moment, I do not. I have had customers ask about them, but usually, it was just an idea they had, and they were not prepared to place an order.

Five-String Double Basses

Five-string double basses are increasingly common, as people want the freedom to reach for lower bass notes, and not have to have a “B-Extension” added to their bass (which can also be done, of course, but it does add length to the bass scroll, and an additional source of fragility.)
I build an occasional double bass, but they are a lot of work, and they completely monopolize my small workspace when they are a work in progress; so I am more likely to default to smaller instruments. There is a special thrill, however, in building a huge instrument, seeing the beauty of the beast, and feeling the floor shake when I draw out long bass notes with the bow. I can certainly understand why players fall in love with the double bass, and especially the five-string double bass, with the lowest-of-the-low B-string at their beck and call.