Thursday, October 04, 2007


My doubts about whether or not to add the sides to the neck first continues. However, yesterday I took yet another step towards doing just that by trimming the sides for the domed back, ready for the kerfed linings to be glued on.

Earlier I had fabricated some small shims that was to function as spacers to raise the sides equal to the thickness of the soundboard,
about 2.2mm around the neck area, and attached them to the solera with double sided stickytape. Well, actually they were a little more than that including the stickytape, but when I squeezed my calipers a little they went down to 2.20mm. Then I put the sides back in the solera and marked the sides at the neck to 78.5mm, measuring from the bottom of the solera, roughly 2mm less than the final height, allowing for the thickness of the back. The same was done at the tail, though here to 84mm, roughly 1.5mm less than the final height. The reason for this was that the soundboard is about 0.5mm thinner around the lower bout than at the neck and the shims were at consistent thickness.

Next, the 15' radius disc was laid upon the whole assemble. In order to have the disc resting at an equal height above the marks at the neck and tail, two shims were added, one to each side around the bottom of the lower bout. I made a little
'marking device' from some scrap walnut by drilling a hole 21mm down from the top, matching the distance from the bottom of the radius disc to the marks on the sides.

I butted the little marker device up against the radiused disc, stuck a white pencil through the hole and traced a line all around the sides creating an undulating line following the radiused dome of the disc. Unfortunately the support blocks on the solera were so high that they got in the way, interrupting the line whenever I bumped into one. However, once the initial marking was done I took
the sides out of the solera and finished the segmented line by using a piece of card as a ruler.

A couple of weeks ago I also made a clamping jig for the sides as an aid for gluing on the kerfed linings. This jig proved to be a very handy asset when it came to trimming the sides to final height. I first tried to plane them without clamping them to anything but it was virtually impossible to control, the jig however, provided a very nice and sturdy support. The sides were planed with my block plane using long even strokes, mostly starting from the waist area, the peak of the dome, and outwards following the bends of the bouts in order to plane with the grain. The plane was first set to a coarse setting but gradually adjusted to fine setting as I got closer to the marked line.







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