Preliminary Carving Top
Marking Back Outline
The pins used to index the top to the rib assembly are seen here as well as the variety of tools I used to shape the top outline accurately. I scribed the exact outline of the ribs and also made use of a spacer to create an outline about 3 mm beyond the margin of the ribs to mark the saw cut.
After the initial carving was completed I formed a flat ledge prior to routing a channel to accept the purlfing inlay
Purfling Ledge
Purfling Channel
I should have mentioned at the outset that my primary resource for building guidance is the lovely book by Chris Johnson and Roy Courtnall, “The Art of Violin Making”. I do however have a library of reference materials about 2 feet long on my book shelf thanks to my dad’s collecting efforts. I managed to work my way through all of it prior to embarking on this endeavor!
With the channel completed, the purfling itself was bent, fitted, and glued into place.
Bent Purfling
Inlaid Purfling
Purfling Closeup
Next comes the final carving of the outside accomplished first with chisel, then small arched finger plane, and finally a thin, very flexible scraper. I prepared a template of the f-hole and located that on the top once the carving was finalized.
Finger Plane
Scraper and F-hole Template
Now for carving the inside. The thickness of the top is not uniform and is described by something like a topographic map into zones of various thickness. Once these areas are outlined I used a drilling method with the drill press to indicate proper depth. A wedge is graduated with appropriate thicknesses marked on it; the board with the vertical peg is mounted on the drill press and then the depth stop is set using the wedge as required. The top rests on the peg and is drilled as needed to mark the thicknesses. After the top is drilled hand carving begins
Drilling Fixture
Drilled Top
Carving Top Inside
Carving Inside Top Complete
Here’s the f-holes in progress
Bass F-hole
F-holes Completed
The bass-bar is now fitted, glued, and carved. I took a novel approach to locating it that some builders may find useful. The notched walnut blocks are temporarily attached with double-stick tape. The notches in the blocks are a slip-fit for the width of the bass-bar and allow a small amount of movement forward and back for accurate rub-fitting of the bass-bar to the top. After gluing, the blocks were released by placing a few drops of acetone at their edges.
Bass-bar
The procedures for the back are nearly identical. It’s getting close to time to glue up the body!
Finished Back
Until next time!
df
Impressive! I like your drill technique for marking the depths of the violin top.
Thank you Robert, but I get no glory for this one. It’s straight out of the book “The Art of Violin Making” by Johnson and Courtnal. I have seen references to similar methods of gauging/marking thickness all the way back to Stradivari (and no doubt earlier) using a needle prick rather than a drill and a somewhat simpler device than a drill press, but the same idea.
Did you use a “cradle” to hold the plates, while carving the inside of the top and bottom?
As shown in one picture the top is screwed to a board while carving the outside (the board is then dogged to my workbench). For the inside I placed the carpet sample on my lap and did the work in-hand — fine for the spruce, a little slow for the maple back. I’m on number 11 now and the last few I have used a cradle and toggle clamps to secure top and back for carving and scraping. Speeds the process up a bit!
I found that a very simple and effective cradle to hold the plates while working on the inside is to use a plastic bag FULL of seeds (rice, lentils, lupin, bird etc) which moulds perfectly to the shape and provides firm support. I got the idea from another website. Cheap and effective. You can tape a couple of bags together to get the size required if using smaller ready packed bags.
Hello Maestro; how did you make that fine flat Purfling ledge? Is there a machine for that?
My current method is to carve it fairly close, rather quickly, with a gouge. Then I mount the plate to a flat surface with screws and use a router mounted to a board to accurately size the ledge. The cut is made free-hand and I stay away from the corners and button, which I generally want to be thicker than the rest of the ledge.