Posts Tagged ‘hot hide glue’

Progress Report: Post #2

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Five-String Fiddle Coming Along Fine!

A day off from work means a long day on Lutherie!

I got up at 5:45 AM (usually I get up at 3:45, so this was luxury), had breakfast, watered some fruit trees, checked e-mail, and got to work. I knew the outbuilding shop where my power tools are was going to get hot very rapidly today (99 deg. F predicted, I think), so I did all I could do out there while it was still cool, then worked in the basement shop for the rest of the day.

  1. I took those rough-sawn ribs and thinned them to 1mm all over, using a fixture I made for my oscillating spindle sander (one of the few power tools I use), and cut out the neck block using my small bandsaw. I have a large bandsaw for cutting up large pieces of wood, etc. That is what I used to divide the back block into the two pieces to be joined at the back center seam (next.)
  2. I then cut out the back and front plate pieces, and joined them, book-matched, so that the grain is nearly symmetrical bilaterally, both front and back. It wasn’t easy this time. I don’t know why. I use a small hand-plane to flatten the edges until they fit nearly air-tight– definitely light-tight. I have a larger plane but this wood was so wild it required a very low-angle plane, set very light, or it tears out at all the curly grain.
  3. I glued the two halves of the front plate together using hot hide glue, and, while it was drying, I cut the ribs to the correct widths and lengths for each of the six pieces, planning as best I could to get the grain to line up appropriately at all junctions.
  4. Once the front plate was dry enough to remove the clamps, I glued up the back plate, in the same manner. Some people get a great center-join using a rubbed-joint method. I have done it that way, but I am more comfortable if I add three clamps after I do the rub.
  5. While the back dried, I planed the front plate to get it more or less level across the inner face.
  6. I took the neck blank and laid out all the measurements on it, and began shaping it a little while I was waiting for other things.

About 11:00 AM I decided I was hungry, so I had a salad and some coffee, and took a picture of the work as it stood:

All the wood in progress.

All the wood in progress.

Back to Work!

  1. I drilled 1/8″ pilot-holes in the scroll block for the pegs. When I drill them early like this I can use the drill press and get the holes perpendicular to the center line. My teacher does not do them this way– he says it risks sags in the varnish, and advocates drilling after all varnishing is complete. (He is probably right, but I can never seem to drill the holes correctly by hand, so I will risk the varnish issues.) I was right about working early in the outside shop– it is really getting hot out there now.
  2. I used the small bandsaw to cut the side cheek excess wood off the pegbox, and trued up the heel where it was too long. From here on out the scroll will all be hand-work.
  3. I used the electric bending iron to bend all six ribs, as well as the front linings. I will have to make some more lining stock– this was all I had for the moment. Fortunately they are easy to make. The linings add strength to the edges of those 1mm ribs, which are otherwise extremely fragile. They also triple the gluing surface of the rib edges, so the joint between the ribs and plates are much more secure. I try to get as much done as I can while the iron is hot, and then turn it off; for one thing, it takes about 20 minutes to heat up: but also, if you forget and leave it on, and then forget it is hot, you can get a bad burn. I keep mine at about 400 degrees F.
  4. I installed the C-bout (center) ribs, and glued them in place with hot hide glue, using wine-cork clamping cauls (donated by a friend) for the small-radius upper corners and broom-handle cauls for the lower corners. (This is really going to be a pretty instrument. The wood is gorgeous. I hope it plays well.) The upper and lower surfaces are an even larger radius, so they will be clamped using a section of large wooden closet rod. Sorry I didn’t take photos of these steps. Wasn’t thinking about pictures…I was just working.

More Pictures

Violin in beginning stages

Ribs and linings bent; Center ribs installed; Upper and lower corner surfaces shaped; Scroll begun.

As you can see, the ribs sprang back quite a bit after being bent. I should have thought ahead and prepared a block to which to clamp them while they were waiting to be glued in place. I have such a block–I just didn’t expect the springback to be so severe.

Close-up photo of the Scroll start

Close-up photo of the Scroll…pretty rough-looking, at this point, but that is how they start out…at least when I carve them.

Scroll layout lines

In this photo, you can see some of the layout lines of the pegbox. The wood is so dark that the pencil lines are hard to see.

As you can see above, after the glue was dry on the center ribs, I worked the final shape on the upper and lower surfaces of the corner blocks to ready them for the upper and lower ribs. Then:

  1. I installed the upper ribs, and, while the glue was drying on those ribs,
  2. I worked some more on the scroll. At this point the simplest way to begin removing excess wood is by cutting from the sides in to very near the layout lines for the scroll volute (the back of the scroll.) I do this by clamping the neck to a work-surface (in this case a lap-board.) and carefully starting the cuts, one at a time, spiraling up the scroll from each side. Usually I can then remove the waste wood with a knife or a flat wood-carving chisel, but the grain in this wood is too wild, so I had to try to follow the cuts around the scroll with the saw, then do the final cutting with sharp gouges and small planes.
Pull-saw and clamp

Pull-saw and clamp.

Wood Removal

Wood Removal.

Meanwhile, the glue was dry enough that I could remove the clamps from the upper ribs and install the lower ribs. When the lower rib glue was dry, I installed the front linings. These little spring clamps are really handy. I got them on a sale once, at Home Depot, for about 37 cents apiece, if I remember correctly. They are just right for this sort of work, and I bought over 100 of them…cleaned ’em out at Home Depot.

Lining clamps

Ribs and linings all installed…waiting for glue to dry.

I had been working on the scroll between other tasks, so it is coming along, too, but I am getting pretty tired, so this is about as far as I expect to get tonight. Here are a few more photos:

Side view of lining clamps.

Side view of lining clamps holding the linings while the glue dries.

Linings

The glue is dry enough to hold, so I am removing the clamps. Here you can see the linings contrasted against the dark wood of the ribs.

Front linings

All front linings visible, here. They will still need to be shaped (tapered and scraped smooth) before the violin is closed up.

Difficult wood.

This is difficult wood to work, but the scroll is progressing in satisfactory manner.

Treble side of unfinished scroll.

Other side (Treble side.)

Back of unfinished scroll.

And, the back; barely begun, but you can see the Volute beginning.

And that is it for today! Too tired…gonna call it a night. It is 11:45 PM

Thanks for looking.

Chet

 

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Latest Violin Repair

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Repairs to Irene’s Violin

(Completed 5/27/14)

This was only intended to be a functional repair, not a full “restoration”. It turned out to be quite extensive, though, and somewhat intimidating at times. The owner is very happy with her “resurrected” violin, so all is well.

Before:

The violin came to me after a mishap involving a water-heater failure, which had resulted in a heavy steaming of an already fragile, old violin.​

Open seams and broken button

The violin had several open seams, obvious from the outside, and numerous older repairs. Some of the repairs were done in a workmanlike manner—some were not. (I am not pointing fingers; just stating a fact…it is a very old violin, and has had encounters with a variety of repairmen.)

Bass side scroll cracks

I could see that the pegbox had sustained some pretty severe damage, but did not immediately detect the cause: as it turned out, the scroll had been grafted (guessing around 1850, just because so many were done about that time, and this fiddle is old enough to have been around for that), and it was/is the poorest job of a scroll-graft that I have personally ever seen. Someone tried to correct it with some patches, but it was in pretty sad shape. I wasn’t sure I could do much to help it.

Treble side scroll--more cracks and worn-out peg holes

The peg-holes were so badly worn that they absolutely required bushing and re-drilling, reaming, and installing new pegs. (As it happened, the old pegs were in fair condition, so I simply shaved them to the correct size after all the pegbox repairs were completed, and so maintained some small sense of continuity.)

When I opened the body (by removing the top/front) I found that there were nearly 50 cleats inside, each to help reinforce the various cracks that had been repaired over the life of the instrument. The entire area around the neck block simply fell off. Some of the old cracks had re-opened because of the steam-bath, but most were holding, it seemed. The whole area under the soundpost area had (and still has) a patch about a millimeter thick, and 35mm by 50mm. Missing wood had been replaced haphazardly in many places, including the entire edge of the plate all the way around.

old inside repairs and relaced wood-- and lots of glue.

Same on the back plate, though not quite so severe:

back plate repairs--old, but mostly sound.

The neck was set incorrectly, with an extremely high overstand (10mm), and low projection, as well as being quite crooked. The ebony crown on the heel of the neck was broken, and simply crumbled, necessitating making a new one.

high overstand and low projection angle

crooked neck and cracked ebony crown

crooked neck

I am not sure what the rationale was with the insert up the back center seam, nor why it had been relocated so far off center. I wonder whether the instrument was originally something larger and was cut down to be what we see today, especially because the f-holes are so far apart.

The button was broken off at the purfling line, which seriously weakened the neck, so, after complete repair of the front plate, I removed the back plate and patched the button by removing a section of wood across the break and replacing it with a perfectly fitted patch, restoring strength to the joint. (Explained later)

The Repair Process: 

(Forgot to take pictures of the actual process…wasn’t in “Photography Mode”… sorry.)

First, I re-glued the section around the neck block which had dropped out—there were several patches from previous repairs that had come loose, but I glued them all back in just as they had been originally, and the joint now seemed secure. There were also some missing sections of spruce, so I replaced them, gluing in new wood. That also seemed to stiffen the area a good bit.

The cleats along the longest cracks were still holding, though the cracks had opened, so I cleaned the cracks with water, then worked hide-glue through the cracks and clamped the plate flat, so that the cleats forced the cracks shut, squeezing out the excess glue. I cleaned off the excess with a warm damp rag, and let it all dry.

Then I could tap the plate and listen for buzzes. There were lots of them! I would tap and listen, tap and listen, and then use a thin blade (palette knife) to pick at various things to find out what was moving. To begin with I found that many of the cleats were only barely holding, and were starting to come loose, so they were vibrating. I glued all the loose ones, one by one. Then I found cracks around the edges, and loose purfling, etc. and glued all of those sources. Finally I found enough of them that the buzzing stopped, and I glued the top back on the violin, after first removing the neck which I had determined to be crooked.

Once I had the body closed, I re-set the neck correctly and straight, ending with a 6mm overstand and a standard height (21mm) at the end of the fingerboard. The result is that I could not use the original bridge (not a surprise), so it got a new (taller) one. As I said, the ebony crown on the neck heel was very thin and cracked, so it simply crumbled off in pieces. I made a new one. It is also very thin, but not broken.  At some point in the violin’s lifetime, someone decided to move the neck (or the back plate?) off to one side…I can’t change that, but you can see the effect at the button—the center line seam is no longer in the center.

After setting the neck, I removed the back so that I could repair the broken button. I carved out a shallow curved scoop almost the full width of the button, and all the way through the neck-block gluing surface—about 1-1/4” long and almost ½” wide, by about 1/8” deep at the center. I used a curved scraper to perfect the shape, then chalk-fit the patch to match it perfectly, and glued it in place with hide-glue. After the glue was fully dry, I planed the patch down to be absolutely flush with the surrounding wood of the back plate. This patch restored the strength of the button, which (unknown to many) is the main strength of the neck joint. (Forgot to take a photo of this—too bad; I was very pleased with it.)

I reamed the peg-holes far enough to get into clean wood, then shaved down some tight-grained Eastern Red Maple into tapered pegs to plug the holes. Once they fit perfectly, I glued them in place with hide glue, and allowed them to dry. Then I cut them off inside and out, using a tiny saw, and shaved them flat with a small carving gouge. I stained the inside with dark brown spirit varnish to match the existing color, and matched the color of the outside of the box to the best of my ability, sanding between coats, and trying to make the patches as nearly unnoticeable as possible. (Bushed peg-holes are always visible, but they don’t have to look terrible. Many older violins have had the holes bushed more than once. This is a first for this fiddle.)

I re-drilled the peg-holes, shifting them a little, to establish a more normal location for each, then reamed them to a small size, and shaved the original pegs down to match the new holes.

I got looking at some of the gaping cracks in the pegbox, and decided I wanted to try to repair them, so I cleaned them out with a small knife and then shaved a small piece of red maple to fit and glued it into the crack. It worked surprisingly well, and I was pretty pleased with the results. Naturally, that required smoothing the patch down to be flush with the original surface, and retouching to match the varnish as best I could.

repaired scroll, bass side

repaired scroll Treble side

The original saddle and endpin were still useable, so they are in place—I think I probably could have used the original soundpost, but I made a new one before I thought of it, so, for the moment, it has a new soundpost. But I suspect that the original is nearly identical, though I used a very thick soundpost. Perhaps later a thinner one could be put in, if it seems too dampened by the thick post.

The nut, however, was very poorly made, and cut so deeply at the E-string that the string rested on the fingerboard. It broke when I tried to re-shape it, so I simply made a new one.

I was able to use the original fingerboard, though it had been coming off, and required some re-work to get it to fit well. I had to do extensive re-shaping and dressing of the surface, too, as it had a very round contour close to the neck, though normal at the wide end. Whoever originally put that fingerboard on did the violin a real disservice: there is a deep gouge of wood missing from the neck itself, all the way up the middle, and a similar deep gouge out of the inside of the fingerboard, so only about the outer third on each side has any contact. This wasn’t something I could change, so I cleaned it up and glued it back together. I assume they thought they were making the instrument lighter. (Not Good.)

Finally, I retouched the varnish anywhere it had been damaged, and tried to give it a good (gentle) polishing all over. I think it looks pretty good, but I never saw it in its “glory days” so I have no idea how that would compare.

finished front

finished side

finished back

The Result:

The owner has a playable violin again. It still has many repairs, some dating before any of us were born, some more recent. I have no idea of its market value, and, in my opinion, that is not important. Its value is primarily that it is cherished by the owner because of who she is and from whom she got it. As long as it is well cared-for, it should still give many years of service.

I uased the original fittings except for the bridge and soundpost, so it looks essentially unchanged from before the damage, except for the peg-hole bushings and repaired pegbox cracks, which she assured me were there when she got the violin originally, nearly 50 years ago.

I never heard the instrument before the damage, so I can’t compare that, either: all I can do is adjust it to what seems optimal now, and trust that, as the owner plays it, it will settle in to sound as good as she remembers it to have sounded. To me, it sounds pretty good, and well balanced.

(Later footnote: The owner contacted me and is thrilled with her violin. She swears it sounds better (and brighter) than she remembers it ever sounding before it was damaged, and she is again playing it in her local orchestra. That is nice to hear…)

Completed violin

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Final assembly of a Davidov model cello

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How to complete the assembly of the cello

Remove the mold and clean up the interior of the corpus.

In my case, since the mold is collapsible and comes apart in several pieces, it is pretty convenient to get the mold out. I use a small electric screwdriver to remove eight drywall screws, and back off twelve more, and the thing just comes right out…no fuss. The twelve that were just backed out are the ones securing the corner blocks and neck and end blocks in the mold. So, here is the corpus, fresh off the mold, with all the blocks still square and rough, and the linings only roughly trimmed, not scraped.

Rough cello interior

Cello interior immediately after removing the mold. All the blocks are still rough and square. Linings still need final scraping.

Rough cello end block

This is the end block. You can see the rounded part that I shaped before installing the front plate, so that I would not risk damaging the front plate while shaping it. The rest of the block was out of reach in the mold. Now it is time to shape all the blocks.

Rough cello corner block and linings.

Here’s what the corner blocks and linings looked like. The linings had been trimmed with a knife, but not scraped.

So– the next hour or so was spent chiseling, planing and scraping all those blocks to their final shape, and scraping the linings as smooth as I could get them. Here is what it looked like afterward:

Cleaned cello interior, just before closing.

I tend to make my neck and end blocks a little oversize. I have seen blocks split and break, because they were too small…it seems an easy way to insure against that sort of thing. All the blocks are now the size and shape I want them, and scraped smooth.

Install the Back Plate

So, the next step is to get the back plate in place. I aligned it carefully, checking all the margins to see that the overhang was fairly even all around, then clamped it in place, dry, using spool clamps. After I was satisfied that the overhangs were correct AND the elevation of the fingerboard was correct (an easy thing to mess up, as the corpus is quite floppy at this point), then I clamped everything solidly, and began removing a few clamps at a time, and inserting hot hide glue, using a palette knife. I washed off the excess glue with hot water, and re-tightened all the clamps.

Here the cello is in all its spool clamps, with one bar clamp to secure the button to the heel of the neck.

Callo back installed with hot hide glue and spool clamps.

The cello back is fully installed, with hot hide glue and spool clamps. The bar clamp secures the back button to the neck heel.

Cello glue drying by woodstove.

The house was pretty cold this morning, so I decided that the cello would dry faster in a warm room. Close to the woodstove (but not too close) is the best place I could find.

Final edge-work, scraping, preparation for varnish

After the glue was thoroughly dry, I removed all the clamps and began trimming edges, and perfecting the scroll and heel. The heel was almost a half inch high (which I expected…we leave extra, so that the heel and button are trimmed and shaped together, and match perfectly when we are done.) The scroll was still quite rough. I spent the rest of the day and late into the evening, scraping and planing, and trying to get the cello ready for finishing. Finally ran out of steam about nine PM, but it is nearly complete. Here is what it looks like tonight:

Cello in the white from front side.

Cello in the white, from the front. A little more edge-work to do, tomorrow morning, and I can begin the finish work.

Cello back in the white.

And there is that one-piece back…it has come a long way since that big slab we started with, hasn’t it? I still have some final smoothing of edges, etc. to do, then it is time for varnish.

Actually, I typically use a very weak water-base stain first, which will make the spruce a tan color, instead of cream-colored. Then I will sand it lightly with fine micromesh, seal it, and start applying varnish. (On the home-stretch, now!)

For those wondering about the pegs, saddle, nut, etc.; I wait until the varnish is complete before adding those fittings.

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Cello Neck-set

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Here’s how I set the neck of a Cello

I’m quite sure it is virtually identical to how other makers do it, with one possible exception: I set the neck while the corpus is still on the mold, with only the front plate installed.

Cello corpus on the mold; front plate installed;

Lay out the mortise outline.

I lay out the center of the neck block, and perform the remaining layout from that centerline. The heel is to be 30mm wide, and the front of the neck where it joins the corpus is 42mm wide. So I mark 15mm to each side of the centerline at the heel, and 21mm to each side at the front plate. Double-check everything. It is a real pain trying to put wood back.

I check my measurements, and mark the location on each side of the neck where the front plat should sit when all is complete– 280mm from the top of the fingerboard, and 20mm down from the top of the neck at the front.

Then begin cutting.

I have five measurements in mind, which I check constantly:

  1. I want the neck centered, obviously, but in terms of simple location, I accomplished that by careful layout– I want it centered, in that the fingerboard will be centered on the corpus, and the centerline of the scroll will be in line with the centerline of the front plate, as well.
  2. I want the neck straight, in the sense that it is not rolled to one side or the other. I can check this by sighting across the “ears” of the scroll at the edge of the front plate. If they seem parallel, I am satisfied.
  3. I want the neck the proper length. That 280mm mark I put on each side of the neck will let me know when I am getting close.
  4. I want the front of the neck the right height off the front plate. That was the 20mm mark I put on each side of the neck.
  5. Finally, I want the neck angle to be such that the bridge will be an appropriate height. I aimed for 65mm at the end of the bridge, so as to arrive at an 82mm projection at the bridge– the bridge, then would be roughly 90mm tall at center. There is some flexibility on this one, but not a great deal. In reality, all five of these measurements simply have to be within tolerance, or the instrument will not work right.

So, with all of that in mind, I measure from the 280mm mark to the end of the neck, to see aproximately how deep the neck mortise must be at the front, then use a Japanese pull-saw to slice along my layout lines to nearly that depth. I stay inside all my layout lines, as I want to leave a little room for adjustment.

 

Cello neck-set 1 of 6

I begin by removing the section of front plate affected by the neck mortise, then use a chisel to remove the waste wood from the mortise itself.

The blue lines you can see in the above photo remain from my initial layout when I bent the ribs. I wanted to make sure they were long enough. (It was close!)

Cello neck-set 2 of 6

I try to get the mortise nearly right on the first try, but deliberately leave some room for adjustment.

Cello neck-set 3 of 6

You can tell from the location of my layout marks that I still am far from done– but the neck fits fairly well, and I will be removing paper-thin shavings from here on, and checking every step of the way.

Cello neck-set 4 of 6

Now you can see that the layout lines are very close to what I wanted. In fact, I had deliberately marked my height at 21 mm, to give room for adjustment… and it is at 20 mm now, which is fine. The 280 mm mark is dead on target.

Notice that the heel is overhanging the back of the block by nearly 5 mm. That is fine– I will remove that excess wood when I flatten the back of the garland, and the back plate will be the last major component installed.

Cello neck-set 5 of 6

Here is a closer look– the length from the top of the fingerboard to the edge of the front plate is pretty critical. a good player will notice any variation. the overstand (height above the front plate) is less critical.

Cello neck-set 6 of 6

I checked and double- and triple-checked until everything was perfect, then slathered the hot hide-glue into the mortise and onto the neck, then rammed the neck home and clamped it tightly. I checked once more with the clamps in place, to see that the measurements were still OK. (Thankfully, they were!) Cleaned up with hot water and a brush. Now it just has to dry.

That clamping block in the photo above was just a scrap of wood– I cut it to the correct angle, then hollowed out a curved opening to fit the cello neck-heel. I glued a pad of 1/8″ cork into the cup, and it works very well.

And that is pretty much all I got done today. Cooked a roast… fed the cat, brought in the newspaper…that’s about it. Pretty tired.

Later tonight, if I still feel like it, I will remove the mold, and begin the final cleanup of the interior of the corpus. On the home stretch, now… well,  almost! 🙂

(Edit: I did go back and remove the mold, but that was all for that night. 🙂 )

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How I carve a Scroll

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Cello Scroll Carving Made Simple 🙂

There is nothing special about the way I carve scrolls. As far as I know, this is how everyone else does it, too, more or less. I am only sharing how I do it.

Start by tracing and sawing out the profile of the whole neck.

I don’t have a photo of the scroll as a simple profile, but I begin with the billet (About 6″ x 3″ x 20″), and trace my template onto it, then use a bandsaw to cut the shape of the profile. I use a oscillating spindle sander to remove the saw marks, and perfect the profile right to the line. While the profiled block is still “square”–that is, while the sides are still parallel, I lay out the peg hole locations and use a drill press to make 1/8″ diameter pilot holes where each peg will be. I drill all the way through, so that the holes are clearly marked, and are perpendicular to the center plane of the neck.

Next cut out the pegbox and at least a few inches of the neck

I hollow out the pegbox before carving the scroll proper. Some people use a drill to get started. I have done it this way, but it seems a little risky, unless you put some sort of limiter on the drill, to avoid going too deep– and even then it is easy to go out of bounds. I use a narrow chisel to remove most of the rough wood, then a wider chisel to smooth the inside cheeks of the pegbox. I also saw off the excess wood on the outside of the pegbox, and plane those faces flat.

Then draw the shape of the scroll itself.

Usually we use a template for this, as well. Some people plot out each scroll with a straight-edge and compass. I have neither the time nor the inclination. In this case, my templates came from a poster of the 1712  “Davidov” Stradivarius cello, now being played by Yo Yo Ma. Some information was lacking, and I filled that in from Henry Strobel’s book on cello making.

And begin cutting:

Once the scroll is drawn out, I clamp the neck to my workbench and, using a Japanese-style pull-saw, I begin cutting slots nearly to the layout lines of the volute. I rotate my position a few degrees, and make another cut. I have to be careful to avoid cutting too deeply, but this method allows me to chip away the waste wood rapidly, and the scroll begins looking like a scroll rather quickly.

Beginning the scroll, proper.

Pegbox is complete, volute partially carved. The cut lines are visible on the portion of the volute that has already been carved. Now we will carve the scroll, proper.

Cutting more kerfs to remove wood.

Care must be taken to avoid drifting across the line into the turns of the volute.

Cutting a series of kerfs for wood removal in carving a scroll.

You can see the direction this is going…I will continue to slice down nearly to the line, rotating a little each time, until I have gone all the way around.

Using a gouge to outline the eye of the scroll.

Once the kerfs are all in place, and to the correct depths, I use a gouge to outline the eye of the scroll, so as not to damage it with the saw.

Kerfs in place, and eye of scroll deeply incised. Carving can begin.

All the kerfs are complete, and the eye is deeply incised with the gouge–I am ready to start carving.

Use a flat chisel to remove the waste wood, and the scroll begins to emerge.

I use a flat chisel to remove the waste wood, and the scroll begins to emerge.

Once the waste wood is completely gone the

Once the waste wood is completely gone the “undercut” carving can begin.

Bi-lateral symmetry

I try to make sure the two sides match symmetrically, before beginning undercut. I do the outside fluting last, to avoid damaging it while carving other parts of the scroll.

Bass side of cello scroll, nearly complete.

Here is the bass side of the scroll, nearly complete.

Treble side of cello scroll, nearly complete.

And, here is the treble side.

Cello neck and scroll, nearly complete.

The neck and scroll are nearly complete. I will continue to fine-tune and scrape the scroll, perfecting it as best I can, right up to the day I begin varnishing.

Fingerboard installed on Cello neck, with hide glue and clamps.

I have prepared the fingerboard, and now I have installed it, using hot hide glue and clamps.

So– that was entirely enough for today. Tomorrow I will continue to refine the scroll and neck, and try to get the neck set. If I succeed, then I can remove the mold and install the back plate.

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Front Plate Installed

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Cello Front Plate Installed

Spool Clamps and Hot Hide Glue

I used to be terribly stressed, whenever installing plates– even violin plates. Now I clamp the dry plate in place with spool clamps, then, beginning with the corner blocks and C-bout ribs, I remove a few clamps and use a palette knife to insert glue before brushing the outside of the joint clean with hot water, and replacing the spool clamps. In this way, I can get the whole job done very quickly, and with no fuss.

Outside view of installed front cello plate

Outside view of installed front cello plate.

 

Error!

The fact is, as you see it, it looks as if everything is fine. The next photo shows what I did wrong, though.  If you look closely, you can see that I forgot to remove the front plate of the mold before installing the front plate of the Cello.

Forgot to remove front mold-plate before installing front cello plate.  🙁

So…it is a good thing I now install plates in such a stress-free way. Sure, it was disgusting to have forgotten such an important step. But it only required a few minutes with a heat gun to remove the front cello plate, as the glue was quite fresh when I realized my error. And, after using my handy electric screwdriver to remove all the screws, I slipped the mold-plate halves out and set them aside, and immediately re-installed the front cello plate.

So, what’s next?

I need to finish the scroll, now, and install the fingerboard. I like to set the neck while the cello corpus is still on the mold, so that, once everything is correct, and the neck is glued in place, I can simply plane the heel flush with the back side of the ribs, and install the back plate.  (Yes, I will remember to remove the rest of the mold first! … and clean up the interior, etc….) 🙂

 

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Bass Bar installed and trimmed–F-holes refined. Edge-work begun.

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The Bass Bar is in place and trimmed. The F-holes have been refined, somewhat, and the edge-work is begun.

Bass-bar was #1 on the list!

I installed the bass-bar first thing this morning (chalk-fit to the inside of the plate in the exact location it was to be glued, then glued with hot hide glue).

Then, while the glue was drying, I went and did other things. Swept up the shop, changed the tires on my car (snow tires have to be off this weekend), and designed some display stands for the upcoming show at Marylhurst University. I had intended to begin the graduations on the one-piece cello back plate today, but after I did the tires, I was pretty worn-out, and hurting, so I decided it was time for a break, and, since the glue was dry, time to trim the bar.

Bass Bar in the rough

Here’s what the bass-bar looked like in the rough, when I took the clamps off:

Cello Bass-bar in the rough, viewed from the top.

Bass-bar in the rough, viewed from the top

Cello Bass-bar in the rough, viewed from the side.

Cello Bass-bar in the rough, viewed from the side.

Bass Bar Trimmed and finished:

And here is what it looked like after planing it to the shape I wanted it to be:

Finished cello bass-bar from front

Finished cello bass-bar from front

Finished Cello Bass-bar from side

Finished Cello Bass-bar from side

Edge-work and final prep for finishing

Although you probably really can’t tell in the photos, I have also scraped the entire plate, inside and out, under low-angle light, to get every dip and hump as smooth as can be.

Also, I began the edge-work; I first planed a small (3mm) bevel all the way around the inside edge, then rounded it with a file, to establish the inside curve of the edge. The outside will be treated the same way, after the plate is installed on the garland. It is much easier to manipulate the plate by itself, instead of the whole cello, so I want to do as much as I can before it is assembled.

I also spent time refining the f-holes; smoothing the inner edges, matching bass to treble shape, etc. That, too, is much easier before the plate is assembled with the garland.

Tomorrow I will try to graduate the back plate.

Gotta do taxes, too, though.  (Hooray for Turbotax!)

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Cello top purfled– ready for final arching

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Cello Top Purfled and ready for Final Arching

Fresh Purfling

Here is the cello top, freshly purfled, hot hide-glue still wet. Tomorrow night I will try to complete the final arching and lay out the f-hole perimeters.

I had some distractions tonight, but that is life. Life is what happens while you are trying to complete your projects and plans. Embrace it or fight it, that is simply how it is.

This spruce has very pronounced winter grains, which were hard to cut smoothly for the purfling slot, but the plate rings like a big bell if you tap on it. I think it will probably be a very good cello.

Freshly Purfled Cello Top

Freshly Purfled Top

Anyway, tomorrow evening when the glue is dry, I will cut the channel and begin finalizing the arching. If I get it close, I will try to get the f-holes laid out and outlined. After that it will be time for graduation of the plate (carving the inside arching).

Press on!

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Cello Back freshly purfled

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One-piece Cello back purfling complete.

Narrow (violin-style) purfling, like the original

Today I completed the back plate purfling. Though this is a cello, I purfled it with violin-style purfling, as it was pointed out to me by Jacobus van Soelen that the original instrument (1712 Davidov Stradivarius) had narrow purfling, like a violin, not the wide purfling I used on my first cello (and which I actually like to use on violins and violas, as well.) I just like the eye-catching appeal of the larger purfling as a rule. In this particular case, I must concede that the wood is so beautiful that it really does not need additional “eye-candy”.

The job starts with layout and measuring

Last night I laid out the corners, and marked the whole purfling channel using a purfling marker (sometimes called a purfling cutter— but I only use it for marking– I use a knife to actually cut out the slot for the purfling).

Then cutting and fitting

This morning I incised the whole purfling slot, using a small, home-made knife, and then cleaned the waste wood out of it with a purfling pick.

While I fitted purfling into the slot, and carefully fitted the corner miters, the glue-pot was heating up.

Gluing the purfling

When all the purfling seemed to fit correctly, I tipped each center-bout purfling strip up out of its respective slot, so that it pivoted up and out on the two corner miters, but left the ends in the slots, unmoved. I slipped hot hide-glue (quite thin) into the slot, using a palette knife, brushed hot water to flow the glue, and pressed the purfling strip back into the slot, forcing it deep into the groove with a special tool. (Sometimes I use my purfling pick for that job. Today I remembered that I have a plastic wheel on a sturdy handle,  actually designed for forcing the rubber trim into screen window frames. It worked perfectly. :-)) Then I repeated the above process for the upper and lower bouts.

If I start toward the middle of a section of purfling, and work toward the ends, the glue is forced along under the purfling, and squirts out along the edges and, finally, out the ends, and the miters. The result is that all of the piece has adequate glue, even if some spots had been a little skimpy. Then I brushed more hot water to re-flow the glue, and wiped off the excess with a rag.

So– here is the completed back, ready for final arching, and for having the edge channel cut, etc. It will look pretty rough until the gouge slices along the channel, and trims that excess glue and damaged fibers off the top of the purfling strip. Then it will look very nice. (Purfling isn’t only for looks, by the way, on violins– it also helps stop a split from the edge from moving up into the plate…supposedly.) Anyway, this is how it looks for now:

Completed purfling on one-piece cello back, before carving the channel.

The channel still needs to be cut, but the purfling is complete.

Lower treble cello-back corner, freshly purfled

Lower treble corner, freshly purfled

The next step will be to mark an edge margin all the way around, locating the crest of the finished edges, after which I can use a gouge to carve the channel, and begin the final arching.

But, for today, I have a bow to re-hair, so this is as far as I am going with the cello.

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