Violin Making Workbook
Link to Terry Borman's presentation at the VSA Convention in 2014 on "Rogue Neck Setting"
In selecting a fingerboard, your primary consideration should always be, "How much more black could it be?" The answer you're hoping for is, "None. None more black."
The gluing surface of the fingerboard is planed glass-plate flat. 138mm down from the nut end of the FB (the point at which the FB is no longer in contact with the neck) on the gluing surface, a .5mm lift is planed into the board.
The sides of the FB are now planed so that the nut end of the FB is 24mm wide, the bridge end is 42mm wide and the mid-point (138mm down from the nut) is 31.5mm wide. When viewed from the front (anterior) or when sighting down the side, there will be a noticeable scoop in the FB's profile. Take care to make this scoop even on both sides of the FB.
The front, or playing surface of the FB is now planed to height. When held in a FB cradle, use a ruler to measure the height at the nut and bridge ends of the FB. The height at the nut end will be 7.5mm. The height at the bridge end will be 11mm. Take care to make these cuts parallel with the gluing surface of the board so that the thickness of the board is constant across its width. Additionally, make sure that the playing surface of the board is flat (or slightly concave-no more than .5mm at the mid point) between these two reference points.
Position the FB on the neck with the apical (nut) end on the line marking the inferior surface of the nut (5.5mm "down" from the pegbox). Use one straight edge on either side of the FB to visualize the FB line-up on the neck in relation to the pegbox and scroll. Clamp in place with two F-clamps, and scribe the lateral sides of the FB onto the neck with a knife. Scribe lightly and lean slightly away from the FB to keep from cutting too deeply into the neck and complicating neck carving as the work progresses.
Bandsaw to the scribe line. Transition out of the cut in the space left for the nut. Leave plenty of room here for blending-in later.
With a divider, lay out a center line on the neck. Measure down 138mm (that's a neck length of 131mm and an inset of 7mm) from the nut/FB junction, and mark a line perpendicular to the center line of the neck. Use an angle gauge and mark a 87.5 degree angle on the lateral sides of the neck (if the neck were a perfect rectangle, the posterior aspect would be shorter by the amount equal to 2.5 degrees). Now mark across the posterior aspect of the neck, connecting the two angles you just marked on the sides. Bandsaw to within 1mm of this line, and bevel down to the line with a knife or a chisel (the bevel on the posterior aspect can go beyond the line, as this will be the direction of your cuts, and will thus minimize any splitting-out of the neck foot).
Soften the end grain with water, and use a broad bladed chisel to waste-off the excess down to the line. Trim and smooth with a block plane. Set the neck foot on a flat plate, and check for any wobble. Make any cuts with the block plane necessary to even out the inferior surface of the neck foot. With an acrylic drafting square resting on the flat plate, check the alignment of the neck foot with the center line drawn on the neck and the center of the scroll. Make necessary adjustments.
Spot glue the FB to the neck with 2-3 drops of yellow glue. Check alignment with straight edges as above, before clamping in place.
Layout the height of the neck foot on the inferior surface by marking down fron the FB 7.25mm for the overstand, 4mm (or whatever is appropriate for your instrument) for the thickness of the top edge, and 30mm (again, whatever is appropriate for the instrument you're building) for the rib height.
Glue size the neck foot with hide glue and allow to dry. Scrape the sizing off, down to the level of the wood. You should have a smooth, glassy surface when you're finished.
Find Your Center (mantra-less)
Find the center of the back of the instrument by measuring the widest points of the upper, lower and C-bouts, dividing these in half and marking those points, lightly, in pencil, on the back of the instrument. Visually line these points up with a straight edge, and lightly mark this line on the button. If God loves you, the center line on the button will correspond to the center seam on your two-piece back.
Find the center of the top of the instrument by measuring the widest point of the upper and lower bouts, the distance between the proximal border of the upper lobes of the ffs, and the distance between the proximal borders of the connecting bars of the ffs, just above the notches. As above, divide these each in half, and lightly mark the points in pencil on the top. If you've done everything right and kept your alcohol consumption to a moderate level throughout the construction process up to this point in time, chances are still pretty good that all four of these points aren't going to line up anyway. The two most important references are the mid points between the upper lobes, and the notches. Connect these points with a straight edge, and mark the resultant center at the top edge of the instrument. This point will always correspond perfectly with the center of the back.
With the center of the button established, you can use a pair of dividers to lay out the button.
Use a knife to carve the button to within 1mm of its finished dimensions.
Use a divider to find the center of the neck foot just below the FB. Extend this down the neck foot with a square, and use the divider to lay out the width of the button at the bottom (posterior aspect) of the neck foot. Allow an extra 1mm on each side for the time being. Use a straight edge and draw a line connecting the points representing the lateral margins of the button with the sides of the FB.
The wood on the lateral sides of the neck foot now needs to be hogged off. This can be best accomplished with an in-canal gouge, broad chisel, or an idiot chisel. Use the lines just marked on the inferior of the neck foot for a guide. Also use the lateral edges of the FB when viewed from the front to guide your cuts. Switch to a block plane when you're within 2mm of the finished dimension. The sides of the neck foot need to be perfectly flat. Check frequently with a straight edge to see that they are. Not only do they need to be flat, but they also have to be parallel to the lateral edges of the FB (when viewed from the anterior aspect of the instrument). By leaving the posterior angle 1-2mm wide of the layout lines at this point, you can buy yourself some "wiggle room" when fitting the neck foot to the mortice later on.
Set-up of the instrument really begins with the layout of the neck, and it's one of two areas (the other being fitting of the bass bar) where Terry devotes a great deal of time and attention to detail. Having said this, we concede that it's really easy to screw up. Keep the following in mind:
Under ideal circumstances, all points on the center lines of the top and back will line up perfectly.
These ideal circumstances will never occur.
When establishing the location of the neck mortice in the body of the instrument, the center line of the top (between both upper lobes and connecting bars of ffs) is more important for the layout than the center line of the back. On a one piece back this doesn't matter because there is no visual center line caused by the center seam of the back. On a two piece back however, if the line-up of the neck set deviates from the center seam of the back, it is glaringly obvious. In cases where this occurs, it is possible to adjust the angles on the layout of the neck foot so that the center of the FB aligns with the center of the top, and the center seam of the back still appears to be the center of the neck foot.
If you thought all of that was complicated, just wait. When transferring the width of the neck foot to the corpus of the instrument, we are going to deviate .5mm from the center line of the top toward the treble side of the instrument. This eases play by slightly displacing the FB toward the player's hand.
Before going any farther with the neck set, some profiling of the neck needs to be done. With a fine-cut rasp, bring the thickness of the neck (ant-post) down to 20.5mm at the neck foot and 19mm at the nut. Blend these dimensions in at each end (neck foot and pegbox) and carry the blending up the sides into the lower third (posterior third) of the FB.
A word of WARNING: You're going to be working with the corpus of the instrument, holding it up at an angle against the top surface of your bench. Do not at any time let the button of the instrument bear against the edge of the bench. Keep the button well above the bench surface, and pad the front of the bench with a scrap of carpet or thick leather. Take heed, lest you become one of those instrument makers familiar with the time consuming button graft.