Maple is a lot tougher to carve than Spruce is, and European Maple is tougher than the domestic maples. But it has to be done, so, we get going on it. I chose to carve the back plate for the Titian model violin, first.
Beginning Planing, using a toothed plane.
Later, as I came nearer to having the plate correctly shaped, I switched to a smooth, curved-sole finger plane. I have two main toothed planes, to which I have affixed wooden handles, so as to distribute the force across my palm, instead of concentrating it on my fingers and thumb. I don’t need the handles as much, using the smooth planes, because I am usually making shallower cuts.
Checking relative curvature with a straight bar.
The arching is still pretty rough, but it is beginning to take shape.
After the shape is nearly complete, I switch to scrapers, and try to accurately match my arching templates. Finally, I use a flexible scraper with which to smooth all transitions, and leave a finished surface.
Arching is nearly finished.
Completed Titian back plate with Plowden plate just begun. (Using a smaller toothed plane.)
It is interesting to see the different wood colors. I bought both from the same source, but they are certainly not from the same tree. That is OK. Both are good European Maple, and will work very well.
Both plates nearly complete–the Plowden plate still needs work.
I was getting too tired to go further this evening. My hands were beginning to hurt, so it was time to call it a day. After I finish the scraping and shaping of the Plowden back plate, it will be time to begin the interior arching (graduation). Also, I ordered a different pair of neck blocks, because I realized that the pair of neck blocks I had were actually Viola neck blocks, and I hated to waste them. So, when the new blocks arrive, I will also lay out and begin carving the two necks and scrolls.
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As I work by myself, I frequently fail to take pictures. I did take a few, though. (If you are impatient, you can scroll down and peek at them.)
F-holes Cut Out
I used a special tool to begin the cutting out progress: It is called an “f-hole drill”, but all it really amounts to is a specialized twin-blade hole-cutter. My children bought it for me, one year, and it has been a wonderful tool. In the first place, obviously, it is a time saver, but the biggest difference is that I can now make the upper and lower eyes of my f-holes perfectly round, to begin with, and work any special shaping in, starting from the already round holes.
I remove the waste wood from the uprights of my f-holes with a small sharp knife—many makers use a saw, and I have done so as well, but I eventually reverted to the knife. Just personal preference, I suppose.
Bass Bar
Once the f-holes are cut out and close to perfect (always allowing for later nit-picking), I install the bass bar. The bass bar is a gently-arched brace supporting the bass-side foot of the bridge. Guitars have a whole collection of similar bracing, supporting what amounts to a nearly flat (and very thin) plate. The violin family instruments depend primarily upon the compound curves of the arching to supply strength, and only need the one brace to support the bass-side bridge-foot. The other side of the bridge is supported by the soundpost, which, while it is not directly under the treble-side bridge-foot, it is very close to it, and is in a location on the treble side matching the lateral position of the bass-bar on the bass side.
I lay out the position of the bass-bar, and then use a compass to transfer the shape of the inside of the front plate to the bass-bar blank. Then I use a knife to remove most of the waste-wood, and begin checking the results against the inside curve of the front plate. When the fit is getting close to correct…close enough that it is becoming difficult to see what needs to change…I apply a strip of paper-gauze adhesive tape (available in pharmacies) to the inside of the plate, covering the bass-bar position, and I rub blue chalk into the tape. I happen to use a product sold as “sidewalk chalk;” they are big sticks of chalk, and supposedly are easy to wash off of sidewalks. But they work well for me, and the blue is high-enough contrast that I can see it easily.
I press the nearly correctly-shaped bass-bar into the chalked tape, and check to see where the chalk transferred. I cut, plane or scrape just the chalked places from the bass-bar, repeating until, finally, when I press the bar into the tape, the whole thing comes up lightly coated with chalk. Then I remove the tape, clean off any remaining chalk from both pieces of wood, and install the bass-bar, using hot hide glue and clamps. I have a specialized set of wooden clamps made for this task.
When the bass bar glue is completely dry, I remove the clamps and trim the bar to the desired shape. I make my bars a little higher than most luthiers do, in the center, but tapering to about 5-6mm high for the last few centimeters of both ends. (I will take some pictures after I remove the inside mold, so you can see the final shape.)
Edge Preparation
It is much easier to do the inside edge-work if I do it before I install the plate on the garland. So, I use a tiny finger-plane, along with round and flat files, to round the inner edge of the plate, all the way around the perimeter. I may have to do a little correction later, but I want it as close to perfect as is possible, before gluing the plate to the garland.
Installing the Front Plate
I line up the plate on the garland as accurately as I can, matching the center-line of the plate to the centerline of the garland, and then use spool-clamps to hold it in place. I was originally taught to use tiny pins to assure good placement, but eventually discontinued the practice. We know for a fact that the old masters did this, as we can see the remnants of those wooden pins in their violins, still today. Perhaps I will eventually resume using pins. For now, I do not.
Once I have the plate perfectly aligned and securely clamped, using a very thin palette knife, I slip hot hide-glue into the joint between plate and garland, and then add more spool clamps to draw the joint closed. This is a very “stress-free” way to glue plates in place. I used to experience near-panic every time I installed a plate, racing to clamp the joint before the glue gelled, but now it is a very easy and relaxed task.
Purfling
As you may remember, I have not yet installed the purfling. I wait until the plate is on the garland before purfling nowadays, because the purfling “locks-in” the location of the plate edge, and I have had problems in the past with the rib garland changing shape a little, between my tracing the plate and trying to install it. so, after gluing the plate to the garland, the first step is to double check my over-hangs, to see that they are all pretty close to the same. If I need to change them, I do so: I am free to adjust the shape of the plate to match the garland again. When the overhangs are all acceptable, I begin purfling.
Purfling is fairly simple-sounding:
mark the groove location
cut the groove,
fit the purfling,
glue the purfling,
mark the edge crest, and
cut the channel.
It sounds easy, but I still find it a hard job to do perfectly. I want my miters perfect, my bee-stings clean and sharp, and all my borders parallel. This is my 30th instrument from scratch, and I am still finding it to be challenging. Guess I am a slow learner. 🙂
Cutting the Channel
Before I begin cutting the channel I use a compass to mark a line all the way around the instrument, 1.6 mm in from the outer edge. Then, using a sharp, curved gouge, I cut my channel to that edge crest line, trying to cut the whole channel to intersect the surface of the purfling and that pencil line.
Fairing in the Channel to the Arching
Once I have the purfling completed and the channel cut, I still have to fair-in the surface of the rest of the plate to match the curvature of the channel. I do not want there to be any sudden changes; humps and hollows catch the eye of the person looking, and call into question the skill of the maker. (Besides, I think they are ugly….) I use a very sharp finger-plane to begin shaping the surface of the plate and approximating the final curves I want. Finally I use sharp scrapers to bring the curvature of the whole plate to its final shape. I use a low-angle light to cast shadows from any humps or hollows, so that I can spot them and scrape them away. At this point, the scraper has to be sharp, and I have to use a gentle touch. The changes I am making are frequently much thinner than a piece of paper.
Outer Edgework
After the whole plate is the shape I want, the last task is to shape the outer edge. I begin by using a tiny finger-plane to take the outer corners down at a 45 degree angle, then use half-round files to shape the edge all the way around, bringing the curve of the outer edge up to just intersect the edge-crest line I established earlier. I get it as smooth and even as I can, using a file, but I know when I stain the wood with coffee, it will raise the grain terribly along these edges, so I will eventually re-smooth all of them, using abrasive paper of some sort. In this particular case, I did the outer edgework after setting the neck. No special reason…that is just what I did.
Neck Set
I measure carefully, and cut the tapered mortise using a razor-saw, then use a sharp chisel to remove the waste wood of the mortise. If I do the job correctly, it works very well. I check the sides and bottom to the mortise to see that they are flat and straight, then begin attempting to fit the neck. I have already joined the fingerboard to the neck and have shaped the heel where it will join the neck-block. So, from this point forward, all the shaping and adjustment will be done to the mortise, not the neck. When I am satisfied that the fit is correct, the neck will have to be centered. straight with the centerline of the front plate, straight with the centerline of the end block (not twisted at all), and at the correct angle to place the end of the fingerboard at the right height. Also, of course, the neck has to be set so that the distance from the nut to the edge of the front plate is correct. I check and re-check, until everything works correctly. Since I set the neck before installing the back plate, I want the heel of the neck to protrude past the back end of the neck-block. I will plane it flush after the glue is dry.
Here is the completed mortise, cut for the neck. The outer edgework has yet to be completed. You can see the edge-crest marks.
The mortise is complete, and I am ready to set the neck.
There is the dry-fit neck set. Notice the overhang of the heel of the neck beyond the neck-block. That will be planed off after the glue is dry.
So there is the dry-fit assembly. It is starting to look like a viola!
When every measurement is correct simultneously, and the fit is tight, I remove the neck one last time and slather hot hide glue into the neck mortise. Immediately I jam the neck into place, and quickly check all those measurements again. Bingo! They are all correct, and I can relax while the glue dries! Once the glue is dry, I plane off the neck heel overhang, flush with the neck-block.
The glue is dry, and the neck-heel overhang has been planed flush with the neck block. I am ready to remove the mold.
In this picture, I have filed the outer edge curvature already, and, though you can’t see it in this photo, I have also completed the graduations on the back plate, and have filed its inner edges, so it is ready to install. But; before I can do that, I have to remove the mold and add the back linings.
Ready to remove the mold.
Dreaming of the next step!
I am getting tired, though, and have some other things that need doing, so the viola will have to wait until another day to move any further toward completion.
Thanks for looking.
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We had just completed the graduation in the last post; Usually, by this point, I am beginning to see the interior of the f-holes, too, because, as you may recall, I had incised them pretty deeply. In this particular case, I could just barely see some portions. I guess they were not as deep as I thought they were.
Once the inside is complete, I finish cutting the f-holes. Many people use a jeweler’s saw, a fretsaw, or a coping saw to cut out the f-holes. I generally just use the knife, except that I do have a special tool for cutting the round upper and lower eyes. I didn’t take any photos of it this time…here is one from an earlier instrument:
F-hole drill being used to cut the lower eyes on a cello.F-hole drill with completed eyes and cut-out plugs.
F-holes Completed and Clean
Just getting the f-holes cut is only part of the job…they need to be clean, and smooth, and relatively symmetrical. I will keep touching them up and tweaking them until the day I begin the varnish, most likely, but here they are; close to being complete, if not completely done.
F-holes essentially complete.
By the way, you may have noticed that on this instrument (and the last one) I purfled after installing the plates. I was taught to purfle early, but I always had trouble getting my overhang even, and my purfling parallel to the ribs. So I tried purfling after closing…works fine and looks better. Diff’rent strokes, I guess….
Bass Bar
When the f-holes are complete, and clean, I can fit the bass-bar. The bass-bar is a spruce brace supporting the bass-side of the bridge, and providing for a good sound on the low strings.
I lay out the location of the bassbar, 1/14th of the width off center, at both upper and lower bouts. It usually ends up about 15 mm off center at the lower bout and 12 mm off center at the upper bout. (Those were the exact measurements this time: the upper bout was 168mm wide and the lower was 210 mm wide. So 1/14th of each was 12mm and 15mm respectively.) When I lay the bass-bar blank along that line, the side of the blank should just about “kiss” the upper eye on the bass side. I make slight adjustments as needed to make sure it does not obstruct the f-hole at all, then scribe the line in with a flexible steel ruler and a soft pencil. The line ends 40mm from each end of the plate, so the bassbar is just under 11″ long, (and about 7mm thick where it contacts the plate, tapering to 5mm along the free edge.)
Bass-bar layout lines complete.
Chalk-Fit Trick
Then I do something a little unusual: lots of luthiers chalk-fit bass-bars…in fact, probably most of them do. I have only known one or two who can successfully “eye-ball” the thing in. But I do not like the looks of chalk-residue mixed with hide-glue, either. I can’t see the white chalk clearly enough to use it, and the others leave an ugly residue– expecially the green or blue chalks.
So… what to do? Someone, years ago (can’t recall who…probably my friend Jake Jelley), pointed out that the paper gauze tape sold in pharmacies will stick securely, you can see the line through the tape, and it holds the chalk very well. The tape (3M Micropore) is so thin and fragile that you get a very good fit, but when you take the tape off after the fit is perfect, all the chalk comes off with it. (Careful! It can pull splinters off, too!) Hey, Presto! Clean wood, and you are ready to glue in the bass bar!
Pre-Fitting the Bar
I pre-fit the bass-bar by eye, using a compass to mark the contour from both sides, then trimming with knife and plane until the fit is close.
Bass-bar pre-fit by eye, using a knife and plane to trim the wood to a close fit. Chalk-fitting is next.
Then I apply the paper tape, darken the line on the tape as needed, and begin the chalk-fit process. It is important to learn to JUST plane or scrape away the portion of the bass bar with chalk on it, on each try. Don’t plane off whole sections…it is possible that only that one little place with the chalk was high.
There is the paper tape…you can still see my layout lines.Beginning chalk-fit.Chalk-fit complete, and tape removed. Notice the arrow on the upper end of the bar: that is to keep me from forgetting which end is which.
Final Check and Installation
I check the fit by clamping the bar in place, dry.
Dry fit and clamped for final check. Seems to fit acceptably…
Then I remove the clamps, and slather on the hot hide glue–carefully. I quickly re-position the bar and clamp it securely, then clean up, using hot water and a brush. The small amount of watered-down glue soaking into the wood around the bar doesn’t seem to hurt anything, so I don’t worry about it.
Bass-bar glued, clamped and brushed down with hot water.
Shaping the Bass Bar
When the glue is completely dry, I remove the clamps and shape the bar…”just so”.
The glue is dry… see the sketched-in proposed shape of the finished bass-bar. The dark area beside the bar is just a shadow, not glue.
I do not have a “scheme”, here, and I do not measure it beyond occasionally checking the center height. I am just going by feel, by eye, and by experience. I know if the bass bar is too weak, it will affect the sound of the bass string…so I err on the side of a tall bar. I am certain that many will frown upon this. I am not telling you how you should cut a bass-bar; just sharing how I handle mine.
So; I use gouges and finger-planes initially, to shape the bar, finishing up with scrapers, files, and even sandpaper. (Yes, I know…but it’s OK, honest!)
And…there’s the plate, completed and ready to install! Well…sort of….
The glue was a little too thin on one end of the bar and it popped off for about a 2″ section. So it has been re-glued and is drying.
Bass-bar nearly complete. One end popped loose, and needed re-gluing.I will do a little final shaping before calling it done.
Besides, the inner edges of the plate will have to be rounded and smoothed before I can actually install it. But there are probably less than 30 minutes of work left before I can glue the front plate in place. So it’s almost done. I hope to install it tomorrow, but I have some other things to do, as well.
Some of you may wonder why I install the front plate first; I was actually taught to do the back plate first, and to install the neck last, but it finally occurred to me that I could fit the neck before installing the back plate, and before removing the mold, and get a perfect neck-set, then trim the back of the heel flush with the rib plane, and install the back last, after removing the mold and cleaning up the interior. It worked very well, so I have continued the practice. Again; different ways of doing things result from different skill-sets and different problem-solving methods. There is nothing wrong with either way. (I even knew of a fellow who set the neck before installing either plate…but I can’t see that one. On the other hand, that guy made over 1000 instruments before he died, and sold every one of them; he must have been doing something right.)
So, the next post will involve completeing the neck and fingerboard assembly, installing the front plate, and setting the neck. Could be a week away; I am going to be working a lot of overtime on my day-job, for the next several months it seems.
Later the same evening:
Bassbar is finally complete!Side view…lighting is difficult, but you can see the profile.
Thanks for looking.
Chet
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Graduation begins with measuring in the spots where it already feels a little thin, so as not to make a fatal mistake and carve right through the plate. (It happens!)
Once I know where I am free to carve, and where I need to take it easy, I begin by carving cross-grain with a medium-large gouge. I check periodically with a caliper. When it begins looking closer to the right shape inside, I measure again, and double check those special spots.
Beginning graduation, using a gouge.
Then I go after it with a toothed finger-plane. This is really just an Ibex 18 mm finger-plane with a toothed blade, and a wooden handle added to save my fingers. I originally added that handle to keep from blistering my forefinger and thumb, as I had done so on every single instrument up to that point. (That was my #16 instrument– a cello.) I was surprised to discover that it also gave me much more power and control so that I was able to set the blade deeper and carve much more aggressively, taking off much thicker shavings.
Using a Toothed Finger Plane to further the Graduation process.
Once it is smooth inside, and within a millimeter or so of completion, I switch to a smaller finger plane and cut more gingerly, until it is all within a few tenths of a millimeter of the goal thicknesses, and then I finish with scrapers. Here is how the plate looks at that point:
Graduation nearly completed– the skewers are only there to create shadows so that the contiour will show in the photograph.Another view, at a lower angle. There are still a few lumps to smooth out, but the graduation is essentially complete.
Usually, by that point, I am beginning to see the interior of the f-holes, too, because, as you may recall, I had incised them pretty deeply. Once the inside is complete, I finish cutting the f-holes. Many people use a jeweler’s saw, a fretsaw, or a coping saw to cut out the f-holes. I generally just use the knife, except that I do have a special tool for cutting the round upper and lower eyes.
And that is what I will show in the next post…which, hopefully will be sooner this time.
Thanks for looking,
Chet
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