When I first began making instruments, I laid out the scroll with a pencil and simply started carving. That was extremely labor intensive and not very accurate, either. It was very easy for me to lose track of where I was going, and ruin a scroll by carving away wood I really needed. (That is a “bitter pill to swallow,” having to scrap a scroll and start over.)
Learning from a Better Maker
So, what has changed? I observed how a viola maker in Brazil (Luis Manfio, of Sao Paulo) carves his scrolls, on a photo-essay he once posted. He used a fine saw to cut “tangents” to the scroll pattern, and then used the same saw to follow the side surfaces of the scroll and remove the scrap wood. It was a much better way than I had been attempting, so, ever since then, I have followed that path.
Five String Scroll blank, laid out for carving.Volute and pegbox layout.Cutting tangents to the scroll curves.Cutting the volute lines, to remove the scrap wood.The resulting scroll blank still needs more tangents cut.This is how the final tangents look. (Notice, too, an “error” pilot hole. It will be plugged befor the real peg holes are drilled.)
Then I carefully cut away the waste wood from the center area of the scroll, using small gouges.
Using a small gouige to remove the rough wood from around the scroll “eye.”Undercutting the turns of the scroll, using a small curved gouge.Rough carved pegbox and scroll, front view.Rough-carved scroll and pegbox from side and back.Closer view of rough-carved back of scroll.Treble-side view of rough-carved scroll. (Notice that the “error” hole has been plugged.)Bass side of rough-carved scroll.
Installing the Fingerboard
Once the scroll is close enough to correct that it will not be changing much, I trim off the excess wood from the sides of the “handle-portion” of the neck, and temporarily install the fingerboard.
Fingerboard temporarily installed and being shaped along with the neck.Shaping the fingerboard and neck, and perfecting the scroll.
The next step is to install the neck into the neck-block on the instrument.
A customer ordered a new, custom-made Five String Fiddle, and it is on the way! He chose heavily spalted, heavily-flamed, Oregon Big Leaf Maple for the back plate, the sides, the neck and scroll. My wife’s parents gave me the wood from this maple tree.
Ann used to play under and climb on this tree as a child, and we hated to see the tree cut down. Her parents still live there, less than four miles from our house, but they had to remove the tree because it was dying. I have salvaged wood for a few instruments from that tree and they all look and sound wonderful!
Given a choice between Spruce and Douglas Fir, the customer chose the Douglas Fir, for his front plate. This tree was also cut a just few miles from my home. (A famous violin and viola maker, Otto Erdescz (1917-2000) used to make violins and violas with Douglas Fir soundboards. Some of them are still being played professionally, today. But very few luthiers use Douglas Fir. I didn’t either, until a few years ago!)
Not my usuaI Choice in times past
For many years, I refused to try such a thing. But a friend gave me a load of very straight grained Douglas Fir firewood, a few years ago. As I was splitting it, I heard the split-off piece hit the ground, and it rang like a bell! I had never seen such straight-grained, clear Douglas Fir, with zero runout!
Unfortunately, that particular piece was too short for a fiddle. I had to search through the pile for a piece that was long enouigh for a violin plate.
Since then, I have made several such instruments, and they all sound great. (I find that the Spruce is definitely easier to work with, though, and, for classical, orchestral instruments, I still use only European maple and spruce.)
Customer Preferences:
This man showed up at my shop and he played all the five string instruments I had. (He really had not been used to 5-string instruments before, and he laughed for joy, hearing the rich deep C-string on each one. After a short while, he declared, “OK, I’m addicted!”) He played the full range of all of them, and finally settled on my earliest unsold 5-string (#3 on the “Chronology” page) as being exactly what he wanted.
But not to buy that instrument. No! He wanted a commissioned instrument “just like that one!” He had thought things over, and he wanted one that was built especially for him! (Sure! We can do that!)
And, as it turned out, that was a good thing: A week later, thenext customer who came to try out all my instruments also loved that fiddle, but she bought it that day, and drove away! So it is gone!
Which Mold?
I knew which of my molds was the source of that fiddle: I have made at least four off of that specific mold. All of them have sold, now, so, for the moment, there are none available. (This instrument will “solve that problem” momentarily, but it will be gone immediately after completion.)
The commissioning customer also wanted localwood, so that he could say, “My violin was made from a tree on that hill!” So…choosing the wood was the first step.
Choosing the Wood
The model I would use had already been chosen, so that was not an issue. I also knew what the wood source would be: I still have a little of the maple my wife’s parents had given me. And, with the customer’s approval, I chose a clear piece of Douglas Fir, salvaged from the firtewood I mentioned earlier. He loved both pieces.
“Fiddle in the rough!”
Here is a closer picture of the maple:
Heavily Spalted and Heavily Flamed Maple
I book-matched the spruce, by cutting a single billet in two equal halves and gluing them together to make the front plate.
Douglas Fir, cut and ready to joint and glue the Center seam
I laid out the neck outline on the billet I had chosen for the neck, and I drilled the pilot holes for the tuning pegs. Then I cut out the side profile on a bandsaw.
Scroll profile cut out, and pilot holes drilled.
Mold Preparation
Meanwhile, I got the blocks glued into the mold. Then I traced their shapes from my template, so the whole job could begin. I also planed away the rough surfaces of the maple to ascertain that it actually would serve well as the back plate of a new five-string fiddle. And, I found that it was just a little too narrow in the lower bouts.
So, I “transplanted” a small piece of wood from the area above the upper bout on each side and grafted them in on the lower bouts. (This practice is not at all uncommon: It will be every bit as strong as the center seams on two-piece backs. And, once the double purfling is installed, the joints will be nearly invisible, under the varnish.)
Back plate in progress, blocks in the mold, and the shapes traced from the template.
Preparing the Ribs
I had chosen wood for the ribs, as well, and I sawed them to a thickness of a little over 2 mm. I thinned them, using a wooden fixture I made, clamped to my oscillating spindle-sander. The fixture allows me to gradually reduce the thickness to 1 mm.
Here are the ribs:
Rib-stock, sawn and thinned: ready to be cut to size and bent.
Installing the Ribs
Next, I cut the ribs to the correct length and width. I carefully considered which grain from one side would “mirror” which grain on the otherside. I had already been tinkering on the neck, as you can see in this photo, but I will explain that process later. (It isn’t always possible to do everything in a precise order. While I am waiting for glue to dry on one section, for example, I may jump ahead on another piece.) You can see the bookmatched front plate, too.
Bookmatched top plate, neck and back billets in progress, and rib samples, cut to size.
I cut all six ribs, and marked them as to inside, outside, upper and lower ends, etc, as well as which side of the fiddle they would call their home…treble or bass side.
Then I bent the ribs using a hot “bending iron” (actually made of aluminum, but, in the old days, they wereiron.)
(I forgot to take photos of the shaped blocks: Sorry.)
I had cut and shaped the corner and end blocks, already, so I applied a generous coat of hot hide glue to one block at a time. then, I clamped the rib into the block surfaces, making certain that everything fit correctly before tightening the clamps.
First, I installed the center bout ribs, and when the glue had dried, I used the spindle-sander to trim the ends of those ribs to match the curvature of the outer faces of the corner block, so I could install the upper and lower ribs. Here are the upper ribs, glued and clamped:
Center and Upper bout ribs installed, using hot hide glue and clamps.
The lower end of the bass-side center bout rib was not fully tight, so I reglued it and reclamped it. (left lower side of photo.)
Then, when that glue was dry, I installed the lower ribs, by turning the mold upside down in the vise, so I could see clearly. It also meant that both hands were free to adjust the rib position, and apply clamps.
All the ribs are installed, but still need to be trimmed, before installing the linings.
Linings bent and installed
I also did not take photos of bending and installing the linings. (Sorry.) Here are two photos of the result, still in clamps.
Front view of linings clamped in place.Side view of lining clamps and rib garland.
Tracing the plates
Once the linings were installed and the ribs thus strengthened, I could trace the shape of the plates, and begin cutting things out.
Garland and Front plate billet cut to shape.And, that is the progress, so far!
Thanks for looking! I will try to keep everyone posted as to progress.
Last post included the sealer, which, to be honest, looks awfully nice…but it isn’t varnish: it was just a resin dissolved in turpentine, used to lock in the mineral ground and seal the pores against excessive varnish saturation (which could dampen the tone.) It looked like this:
Back view of 5-string fiddle with sealer.
So, from that point forward, the varnishing began:
Early Varnish
The first coats of varnish I use are pretty intensely yellow, as that golden glow will shine through the other colors, wherever there is any wear, or deliberately thin spots in the color coats. Then I begin selectively darkening certain areas, corners, etc. to enhance the overall look and feel, visually.
So here are the front and back after the early coats of varnish: pretty much all from the first day or two of varnishing:
Front view, with early coats of varnish.
Back view with early varnish coats.
Later Varnish
After the early varnish is well-cured, I scrape or sand back any sags, drips, or brush-marks, remove any brush-hairs that might have been overlooked earlier, and then lightly sand over the entire instrument, to produce a smooth surface upon which to deposit subsequent coats of varnish (usually about eight overall, by the time I am done varnishing.)
I add the deeper color coats, still striving to produce the shading that would go along with the old instruments that everyone finds so attractive. (I have numerous excellent photos of “old-master” instruments to study, from which to gain ideas as to what is “normal” wear.) So, here are photos of the front and back of the same instrument after further layers of varnish have been applied:
Front view of same 5-string fiddle with later layers of varnish.
Back view with later varnish layers. I like that back, of Oregon Big Leaf Maple!
Future plans:
I anticipate about two or three more coats of amber varnish to deepen the shine and improve the clarity. There will be some re-touching done as needed, of course, especially after I re-install the fingerboard and fit the pegs, to begin set-up. But this is looking pretty much the way it will when it is finished, in terms of overall color. the red will probably look a little less intense, but it will still be there.
I hope to have it playing next week sometime.
This is the “sister instrument” to a five-string fiddle made last year. Each was built from wood salvaged from the scraps after I built a five-string Double Bass last Summer.
I just began a new website for teaching-related articles, photographs, and videos. The Layman’s Institute will be at http://laymansinstitute.com and will have lots of teaching articles: whether math lessons, violin-making, or anything else.
No content is there, just yet: I will begin adding content in the next few days, I hope.
Fit and install the End Pin. (Already done on this instrument.)
Fit and install the Saddle. (Already done on this instrument)
Fit and install the Tuners (in the case of a double bass, that means “tuning machines.” Already done on this instrument.)
Fit and install the Soundpost. (already done on this instrument.)
Fit and install the Nut, file the string slots to the correct depth in the correct places.
Establish the correct length for the Tail-gut (or tail-wire in this case) and install it.
Fit and install the Bridge, filing the string-slots once the height is correct.
Install the Strings.
Play for sound adjustment, string clearance adjustment, etc.
End-Pin
On violins and violas, the end-pin (usually called the end-button) only serves as an anchor-point for the tail-gut. But, in cellos and double basses, it also must serve as a height-adjustment, so that the instrument will rest at the correct height for the particular player. In this case, I had chosen an Indian Rosewood plug with a tubular steel end-pin fully adjustable and locked by a thumb-screw on the bass side. I installed it earlier, so here it is, without details about shaping the plug or reaming the hole:
Endpin assembly installed.
Saddle
I cut my saddles with a large radius on each of the upper corners, where the saddle is cut into the front plate. There is a strong likelihood, historically, that cracks will eventually develop, emanating from the corners of the saddle. They are so common that they have a name: “saddle-cracks.” There are two ways to try to avoid such cracks:
The first is to make the mortise for the saddle (the part cut out of the front plate) a little wider than the actual saddle, by maybe a millimeter or so, so that, when (not if) the front plate shrinks during dry weather, it will not find itself up against the unmoveable saddle, and be forced to crack, to allow for the shrinkage. This is a good practice, and I try to follow it.
The second is to make the saddle with sound corners so that there is no “notch” in the plate at the “corners” of the mortise, but rather a smooth rounded curve, which eliminates the stress-riser and minimizes the chance of a saddle crack in the first place. (Round discontinuities essentially do not cause stress risers, hence, do not cause cracks.) I always do this, (since about my sixth instrument) and will continue to do so.
I already explained all this, including the purpose of the saddle, in a previous post. Suffice it to say that this part is already completed.
Saddle with round corners, to prevent saddle cracks.
Tuning Machines
There is a wide variety of choices for tuning machines for a double bass. Some are better than others, some fairly plain, but fully functional and reliable, others beautifully engraved or ornate in some other way, and understandably far more costly. Someone had to spend the time and money to do all that “pretty stuff,” so, if you want that, you gotta pay. I chose plain but functional. (They are pretty, too, but not fancy.)
Rubner tuning machine (one of five.)
At any rate, they are already installed on this instrument, as of my last post:
Tuning machines installed on five-string double bass.
Soundpost
The soundpost is a “dowel,” usually of fine-grained spruce, that spans the gap between the inside of the front plate and the inside of the back plate, just south of the treble bridge-foot. My understanding is that it transfers the vibration from the front plate to the back plate, and “couples” the two plates so that they work together to make the sound from the vibrations created at the strings (whether by bowing or plucking.)
There may be (probably is) more to this function: It is an important enough part of the set-up that in some languages, the soundpost is referred to as the “soul” of the instrument, and it is definitely one of the most important adjustments that can be made. It is held in place simply by the compressive force transferred through the bridge by the tensile stress on the strings. Adjusting the position of the soundpost has a profound effect on the character of the sound the instrument can produce.
I already installed the soundpost, but I fully anticipate that I will continue to adjust it as the instrument settles in, in an attempt to produce the best tone, volume and balance that I can achieve in the sound of the instrument.
Soundpost installed, in preliminary position. Adjustments will be made from here.
Nut
The nut is the transverse piece of hardwood (usually Ebony, but in this case Ipé, ) across which all the strings are resting, directly above the fingerboard. It serves as a positive stop for all five strings, so that the strings are not in actual contact with the fingerboard when the player is not fingering a note, but are suspended about 0.5 mm above the surface of the fingerboard. the idea is that an easy touch from the player’s finger should put the string in contact with the fingerboard at the correct position for the desired note. The nut is glued to the neck and fingerboard, usually, but in reality, it is held in place by string tension, and the glue is “just a formality.” (I glue them so that they can’t fall off and get lost, during transport or a string change.)
I carefully laid out the string locations, so that they are spaced equidistant, center-to-center, and then cut the slots for the strings using first a small razor-saw, and then a round file of the appropriate diameter for the string in question.
Nut installed and slots filed for a 5-string Double Bass. The corners will be rounded later.
Tailpiece and Tail-wire
I chose to make the tailpiece of Ipé wood, to match the fingerboard, nut and saddle. The tailpiece fret (transverse bar forming a positive “stop” for all five strings) is also Ipé, and after being heated and bent, it resisted being glued. I eventually took it off entirely, scraped off all the failed glue-layers, washed it down with acetone to remove the oils in the wood, and reglued with epoxy. But this time, I anchored it with six small brass rivets. It is permanent, now! (Besides, I like the look of the shiny little brass rivets!)
I also attached the tail-wire; a 1/8″ diameter stainless-steel aircraft cable. I established the length so that the distance between the nut and bridge would be as close as possible to being in a 6:1 ratio with the distance between the bridge and the tailpiece fret.
Completed tailpiece assembly for a five-string double bass.
Bridge
I chose a bridge blank that was tall enough to serve with the projection angle I had already established, and wide enough to comfortably accommodate five strings.
I fitted the bridge feet to the surface of the bass front-plate, so that it would have an airtight fit when placed between the inner “notches” on the f-holes, and centered over the centerline of the plate.
Once the fit of the feet was established, I marked the bridge for the approximate height, hoping to achieve a string clearance of about 11 mm above the end of the fingerboard, but erring on the side of “too high.” (I can’t very well “put it back,” if I remove too much wood.) I then marked the locations of the strings, giving them 25mm from center to center. I filed the string slots, so that the strings would stay put when installed, and I went ahead and installed the strings.
Bridge for 5-string double bass.
As it happened, I ended up with about 14mm under the B-string, ranging to 12 mm under the G-string…way too high. No problem: I simply re-marked the bridge, this time having a better idea of where things would line up, re-cut the top of the bridge, re-filed the string slots, and tried again. This time I had 11mm under the B-string, and 6mm under the G-string, with the strings in the middle at about 8mm. That is acceptable, so I finished trimming excess wood from the bridge, tuned up the strings, and I was ready for the final adjustments for sound.
Five-string double bass set-up and ready for final adjustments.
It is quite a relief to me to finally have this instrument nearly complete. It was actually begun several years ago; but it was set aside for a variety of reasons, and only resurrected as a project, this Spring.
The sound, at first set-up, is satisfactory, but I hope to achieve a better balance, more volume, and better clarity as the instrument “settles in’ a bit, and with subsequent adjustments of the soundpost. But for now, I’m happy with it. It looks good and sounds good. For a brand-new instrument, that is a good start.
Completed 5-string double bass with cello in the background.
So, for now, that is it! There are a few “finishing touches” and re-touch of varnish, etc, as well as the aforementioned sound adjustments, but the bass is essentially complete!
I hope to make all the necessary adjustments, and then find a player or two to “test-drive” it for me, since I am not a player, and can’t do it justice.
I will post the “verdicts” from those players when they happen.
The color varnish, as you might imagine, gets the instrument looking the way we want, but the clear coats keep it that way…we hope.
So, after the color coats were mostly complete, I waited a few days for the varnish to cure a bit and then added two clear coats as a protection for the color coats, so that they will not experience undue wear.
Final clear coats of varnish on five-string double bass in sunlight.
Final clear coat; Back view in sunlight.
Final clear coats in the shade.
There is still a lot of work left to do at this point: There will be endless “re-touch” of spots in the varnish that I wasn’t quite satisfied with, but they can wait until after the set-up is under way.
Saddle
I usually wait until the varnish is complete, before installing the saddle. The saddle is the transverse piece of hardwood upon which the tail gut rests, as it crosses the edge of the front plate. (Ebony, frequently, but, as I had opted for an Ipé fingerboard, Ipé seemed the right choice for the saddle as well.)
I make my saddles with radiused ends, to avoid saddle-cracks. To some extent, saddle cracks are caused by the shrinking and swelling of the spruce plate against an essentially unmoveable ebony (or Ipé) saddle. However, the other factor (possibly more important) is that, for hundreds of years, luthiers have cut the saddle with sharp-cornered, square ends, requiring a sharp-cornered square-ended mortise in the spruce…which inevitably inclined itself toward eventual cracks. Sharp corners are extreme stress risers.
Round discontinuities (holes, for example) do not cause stress risers, and are far less likely to cause cracks. I try to leave the ends just a little loose, as do most luthiers, but the fact is, the sharp notch is the primary cause of the cracks. So I make round corners.
Saddle with round-cornered ends.
Tuning Machines
The next task was the tuning machines. There are many possibilities to choose from: I chose these tuning machines partly based on looks, partly on cost, but primarily because, with the curvy pegbox, I wasn’t completely sure that any other style could be made to work. (There are some multi-piece tuning machines, which, I would imagine, could be made to fit nearly any configuration, but I have no experience with those, so I opted for something I knew about.)
Anyway, I knew that this type of tuning machine has a tapered spindle, which is not designed to go all the way through the pegbox, so I designed and built a small reamer, all wood, except for the blade, which is spring steel (just because that is what I had available.) It works well, but I have to be gentle with it, and stop periodically to clean the chips from the reamer.
Handmade reamer for fitting double bass tuning machines.
I made a template, laying out the hole locations with the hope that I could avoid the strings from the G and D tuners rubbing on the tuners below them in the pegbox. I used the template to lay out the holes on the pegbox, then drilled to appropriate depths and used the reamer to taper the holes to match the spindles of the tuning machines.
Finally, I installed the machines and secured them with screws.
Tuning machines installed on five-string double bass.
It was amazing to see how much weight the tuning machines added. The bass no longer easily balances on the two bouts: it wants to rock down and put its head on the floor!
Ready for set-up!
I installed the nut at this point, as well, so the bass was really complete.
Five-string Double Bass, ready for set-up!
If you have sharp eyes, you will probably notice the hole above the tuning machines on the bass side. The pegbox was narrow enough there, that I actually went through the second side by accident, and was forced to create a plug for the hole, from some leftover rib material. I cut it to exactly fit the hole, and glued it in place, pressing it home, so that it was nearly exactly flush, then scraped the wood of the plug to exactly match the wood of the pegbox, and was ready to begin varnishing to complete the repair.
Repairs in progress for pegbox damage. When complete, the repair will be virtually invisible.
Anyway… that is as far as I wanted to go today. Some of you may have known from other forums’ content, that I had also had trouble getting the tailpiece fret to “stay glued” in its slot. So I eventually gave up, removed the fret, scraped all the layers of glue down to clean wood, and washed the Ipé with acetone. Then I reglued with epoxy, but this time I drilled and anchored the fret with six brass rivets! (It’s permanent, this time!)
Completed tailpiece.
Next time, I hope to complete the set-up of the bass and have it ready to play!
When I last posted, I showed the garland with the Sitka Spruce front plate installed, and the completed Oregon Big Leaf maple back plate sitting on it (because I wanted to see it that way) with the neck block (also Oregon Big Leaf Maple) beside it. You can see in that photo that I had already installed carbon fiber reinforcement rods, bedded in epoxy, to stiffen the neck. But I didn’t say how they got there.
See the reinforcements in the neck?
The problem with maple is that it is fairly flexible. Usually, that is not a concern, because the instrument necks also have a fingerboard added on (usually of ebony) which is very stiff, so that the flexibility of the maple is not much of an issue. But, when the fingerboards become thin, after years of being used, re-surfaced, and used again, the frequent “re-dressing” of the fingerboards thins them to the point they are no longer stiff enough to bear the stress of the string tension, and the neck begins to bow forward, under string tension.
Carbon fiber is very light and extremely stiff, so it makes an ideal material for reinforcement. Carbon fiber rods are available in a variety of shapes and sizes. I chose 1/8″ x 1/2″, and they arrived in two-foot lengths from the “Dragonplate” company.
I do not have a router table, nor even a table saw, so I used my hand-held circular cut-off saw (commonly called a “skill-saw” as “Skilsaw” was an early brand of this sort of tool.) I set the blade on the saw to 5/8″ deep, and, having already drawn the lines where the cuts should go, I clamped the neck block in the vise, with a block beside it to guide the saw, and simply sawed slots into which to fit the carbon rods. The slots did not fit well, as the blade was not wide enough, so I attempted to use a hand-held router to widen the slots, but I did not have the correct bit for the router, and they were very expensive at the local hardware store, so I carved out the remaining wood, using my knife and a small chisel.
Once the slots were satisfactory, I mixed my epoxy, filled the slots, and pressed home the carbon rods. The epoxy I chose to use was advertised as “15-minute” epoxy, but all it meant was that I would have 15 minutes of working time, in which to get the rods in place, the epoxy smoothed over the tops of them, where it had squeezed out, and be done tinkering with it. It turned out to achieve full cure in about 24-hours… by the next day, in other words. No problem: I had plenty of other work to do while I waited.
Neck block with carbon fiber rods bedded in epoxy, waiting to be trimmed.
So, I scraped all the excess epoxy off of the neck joint face, where it would be glued to the fingerboard, and waited until the epoxy had fully cured, before sawing off the excess carbon fiber rods, using a hacksaw.
Neck block with carbon fiber reinforcement rods trimmed to length.
The result is a five-string double bass neck that will never become bowed or warped.
Ipé Fingerboard and Tailpiece
I chose to use Ipé instead of ebony for my fingerboard and other fittings, as it is more readily available, it is not a threatened species, and I like the finished color (dark brown.)
Ipé is an extremely hard, dense, South American hardwood, similar to Ebony, in terms of hardness and durability. It is difficult to work, as are all the extremely hard, dense, tropical woods, but I like the finished product. Here is a fingerboard on a five-string cello I made some time ago:
Ipe fingerboard on five-string violoncello piccolo.
So, I decided on the shape and size of the fingerboard and tailpiece, and then cut them out on my bandsaw. Then I used gouges and planes to shape them appropriately.
Fingerboard underside being carved of Ipe wood.
The dust from sawing, planing, scraping or sanding Ipé wood is a bright yellow color, and it fills the pores of the wood, giving the wood a greenish-yellow look while it is being worked. But that color disappears entirely when the wood is finished, and the Ipé becomes a dark brown color.
I glued the fingerboard to the neck block when it was nearly complete, and then completed the shaping of the fingerboard with the neck as a unit. The tailpiece, too, is only partially completed.
Fingerboard and tailpiece waiting to be completed. Fingerboard is glued and clamped to the neck.
My wife was a little perplexed about the odd color of the Ipé wood, so, after completing the preliminary dressing of the fingerboard, I used a paper towel, and rubbed the fingerboard down with turpentine, to show the color as it will look when finished. I also rubbed a small portion of the tailpiece, to show the stark contrast between the color of the Ipé when freshly worked, and when finished. (The turpentine is not the finish, obviously, but the color will be very similar, as a light coat of linseed oil rubbed into the wood probably will constitute the finish.)
Fingerboard and tailpiece with turpentine to show the true wood color.
I went ahead and began the shaping of the neck at the same time, so it is beginning to look the way it will be when completed. When the neck shape is correct, I can begin the neck-set procedure. This is the first time I have attempted a removable neck, so I am a little apprehensive about it. All I can do is press on, and see how it works.
Here is how it all looks right now:
Neck and tailpiece for five-string double bass. Notice the “fret” bent and clamped to the tailpiece.
When completed, the tailpiece will accommodate five strings, and have a “fret” inlaid across the upper end, to provide a hard “stop” for all the strings at the same point. The “Fret” is made of Ipé wood, too, bent to shape with heat and pressure, then clamped to the tailpiece to cool in that shape. Next, I will cut the slot in the tailpiece to allow the fret to be inlaid into the tailpiece, and drill the holes for the string-slots and the tailgut wire.
As I was ready to begin the inside carving of the front plate, I realized that the little caliper I use for graduating violins and violas was simply not going to serve. I had a much larger caliper I had built 13 or 14 years ago, when I built my first bass, but it had been hanging in my workshop untouched for all those years and I was afraid that the battery might have corroded and ruined the digital indicator.
I had purchased the electronic tool from Harbor Freight, back in 2006 for about $10 (If I remember correctly,) and built the caliper out of hardware from a local outlet and a scrap of 1″ plywood decking. It was pretty crude, but it worked and was quite accurate.
Bass caliper, hanging amongst molds and templates.
I took out the little “battery-tray” thing, to see if my fears were justified, and it seemed as though the battery had not leaked, but was simply dead. So I went and bought a new battery, inserted it, and “Hey! It works!”
Bass Caliper with large display.
One of the things I like about the tool is that I can actually read the display. My small caliper has such a tiny display that I have difficulty reading it. Notice that it is reading .03 mm when it is not in use. The plywood flexes that much, under the weight of the lower jaw, so I hold the instrument upright and level, and press the “zero” function. Then it reads “zero” when it is held upright, and .03 mm when it is lying flat on its side.
So that was the first tool I was concerned about. The next concern was that I really did not want to gouge out the interior with mallet and gouges, as I had done the exterior. I was fearful of cutting too deep. So, in my mind, a “scrub-plane” with a curved sole was in order.
Curved-sole Scrub-plane
This also was one I began years ago, but did not complete soon enough to use it on the bass, nor even the cellos I made later, so the pieces languished in my toolbox drawer, waiting for me to finish the job.
I had made the body by welding together a slice of scrap stainless steel pipe, and some mild steel plate, along with a little section of angle iron and a 1/4″ pin. The cap iron was a shorter section of the same slice of stainless pipe, and the blade was (if I remember correctly) a piece of A1 tool steel. I had even gone so far as to cut sections of curly maple for handles, but had stopped there, and all the pieces were together in the toolbox. So– the time had come!
Pieces of the curved-sole scrub-plane.
Bottom view of Curved-sole Scrub-plane.
Partially assembled plane.
Completed Curved-Sole Scrub-Plane.
The completed plane, after a little adjusting, worked very well, and fit my hands comfortably, so the task of carving the inside of the bass front plate went very well.
Carving the inside of the Double Bass front plate using the Curved-sole Scrub-plane.
The only fault in the scrub-plane, because of the deeply curved sole, is that it tends to leave a rather un-smooth surface– like ruts in a dirt road. So, as I got closer to the desired thickness of the plate I was going to need a plane with a much less aggressive curved sole, and broader, as well, to produce a smooth surface.
Palm Plane
Fortunately, this one, I had built during my first bass-build, though it had not seen much use, as I never really got it adjusted right, and was busy enough that I just set it aside and completed the first bass using other tools. I got it back out and carefully sharpened the blade and adjusted the depth of the cut, and it turned out to work splendidly, though it took a little practice to get the angle in my grip just right.
Steel Palm Plane.
Steel Palm plane with a wooden finger plane.
All of the planes I have built work on the same principle: a blade is fixed at a given angle, and clamped in place by means of a cap-iron that slides under a transverse pin, and a screw that wedges the cap-iron between the pin and the blade. The principle is very old, and works well. It is used in many commercial planes, and predates all the companies that use it.
This little wooden plane was the first one I ever made. It is made of Padauk wood and is pretty crude, but it works well. (Ibex planes work better, but at the time I made it I had no money for an Ibex plane.)
Wooden plane disassembled. The thin end of the cap iron slides under the pin.
It is not a really tiny plane, but it fits my thumb and forefinger pretty comfortably. The blade was a section of scraper blade, and, while it works, I think I could improve it with a better choice of steel.
Wooden plane showing interior and relative size.
Assembled Padauk-wood plane.
Other Tools
The other tools (below) I had made years ago, and have been using regularly.
Homemade knives from an old sawzall blade.
Homemade gouges, forged from plow-steel or drill rod.
Many of my other tools are homemade, too– spool-clamps, scrapers, work cradles, templates and molds are all hand-made originals, as well as my workbench (which is usually buried in tools and materials…sorry).
So…that’s how I acquire tools! 🙂
Rationale
You might ask, “Why would you go to all that trouble when you can buy professional-level tools for reasonable prices?” The answer is two-fold:
In the first place, I really enjoy making tools! And then, there is a special joy in finding that the tools I make usually work very well, so I then have the pleasant experience of making musical instruments using the tools I made.
But the second reason is financial in nature: I simply did not have the extra money to buy every tool I needed when I began building instruments. But one does not haveto expend a great deal of cash, to get started in a craft, if one is willing to think, read, and learn the skills to make tools.
The time I spend building a tool is repaid many times over, by the pleasure I get in using the tool and the fact that all these tools will be used for many years to come, as I continue to build instruments. Are there sometimes failures? Once in a while an idea doesn’t work as well as I expected, but usually I find it very rewarding to make my own tools.
I had installed the European Spruce front plate on the garland, and showed the partially assembled corpus in spool-clamps. So, here is the partially completed corpus, out of the clamps and stacked with the rest of the parts:
Garland with top plate installed, back plate traced, and scroll begun.
Scroll Work
So, I took a break from working on the plates, and worked on the scroll. It is made of highly flamed European Maple.
I completed the carving of the turns of the volute, and cleared it up until it was nearly complete, including the chamfers around the edges. I used an assortment of small gouges to carve the undercuts, and completed the work using scrapers.
Scroll and pegbox essentially complete. Ready to temporarily attach the fingerboard.
Back Plate Beginning
Then I decided I had better get the European Maple back plate caught up to everything else, so I cut out the traced shape on my small bandsaw, and cleaned and smoothed the perimeter on the oscillating spindle-sander. I began the outside arching, using a toothed-blade finger-plane, and then switching to a smooth-blade finger plane, stopping only because I was getting tired.
I will still have a great deal of careful shaping and scraping before the back arching is truly complete. But before I stopped for the evening, I temporarily glued and clamped the ebony fingerboard to the neck, knowing that I will remove it after setting the neck and before varnishing. So, here is where the instrument sits tonight:
Back arching nearly complete, neck and fingerboard joined.
You will notice that I also began shaping the “handle” portion of the neck. I shape it along with the fingerboard, dressing the fingerboard to get the curvature perfect, and shaping the “handle” part of the neck for optimum playability and feel.
But, when the arching is complete, I can sweep straight on into graduation, because, of course, the back plate has no f-holes, let alone a bass bar. (I do have to remember to install the label before I close the corpus. I don’t enjoy trying to install a label with tweezers, through an f-hole.)
Next Steps
The next things on my agenda will be to complete the arching, complete the graduation, and get going on purfling the front plate.
Many makers install the purfling before they begin graduation, but I always had a problem with the overhang being uneven when I did that, so I switched to purfling after the plate is installed on the garland, and the overhang has been satisfactorily established.
I also usually set the neck before removing the mold, so that, when I go to install the back plate, the neck heel is already perfectly flush with the back of the garland, and the back plate fits flush and tight, all the way around. Everyone has their preferences and idiosyncrasies, I guess.
My expectation is that I should have the neck installed by the end of the week…and maybe the back plate, too. But there are always other demands on my time, so it may be next week before either of those is complete.
The raw wood is quite porous, and would soak up varnish like a sponge…which would dampen the viola sound. So we don’t want that to happen! The solution to the problem seems to be to fill the pores of the wood with very fine particles of mineral of some sort. I don’t particularly want something that would form a concretion, as some makers have done, because I think that also changes the sound, but in a different way.
I used Gypsum, ground very fine in a mortar, then suspended in water, and daubed onto the surface; then vigorously rubbed into the pores. After rubbing the mineral into the entire surface (except the “handle” area of the neck) I used a damp cloth to rub all the excess gypsum back off. While it is wet, it just looks like wet wood, but as it dries, it turns chalk-white, assuring me that the surface is truly saturated with the particles.
Partially dry mineral ground, front side.
Partially dry mineral ground, back side.
Then, after the gypsum suspension is completely dry, I use fine sandpaper to remove any excess mineral from the surface, so that there are no thick patches of mineral.
Dry Mineral ground, rubbed clean.
Locking the mineral ground in the wood: Sealer
As you can see in the above photograph, the mineral isstill saturating the surface, and obscuring the grain. However, when I apply the sealer (in this case, a mixture of rosin, turpentine, and alcohol) the mineral ground will become completely transparent, and will permanently disappear. The varnish will then be free to show off the grain of the wood.
Front side with sealer.
Side with sealer.
Back with sealer.
Making it Shine: Beginning the varnish
It takes a while for the sealer to dry, because of the turpentine content, but as it dries, the alcohol evaporates first, then the turpentine, leaving the rosin in the wood (which is where rosin comes from in the first place, of course) locking the gypsum particles in place. and further sealing the wood against saturation with varnish.
Before proceeding to the varnish, I carefully sanded all over, to clean up any spots that still felt rough or sticky, then wiped the entire instrument down with alcohol to remove any rosin residue from the surface.
Then I applied a first coat of yellow varnish, as I have noticed that many of the old instruments seem to have something yellow under the darker red or brown varnish. You canespecially see it in the areas where the colored varnish has worn thin, or is completely gone. (Not all of them have this color, but I like it, so that is what I have chosen to do.)
So, here is the base coat of yellow varnish:
Base coat of yellow varnish on front side.
Base coat of yellow varnish on the side.
Base coat of yellow varnish on the back side. The grain of the spalted maple is showing better, again.
Base coat of yellow varnish on scroll and neck heel.
I do not apply varnish to the “handle” portion of the neck until everything else is completely done. After everything else is done, including set-up, I will rub down the handle area with 400-grit abrasive one last time, and then put about a dime-sized dot of shellac on a rag, on the end of my finger, and vigorously rub it into the wood of the handle area, until it is completely dry. This somewhat seals the wood against sweat and dirt, without leaving a heavy, “slick” coating that would cause drag on a player’s hand.
The rest of the varnish coats will be building color toward the final look of the instrument. I will include them in another post.
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