Marking the side profile.

Getting the side profile close to final before gluing in the kerfing makes the contour sanding much easier and more controlled.

To mark the sides I support the concave dish on three 1/2" dowels.

The rear dowels are exactly the same length and placed in line with tail of the guitar shape and about 5" on either side. They must be

absolutely symmetrical.

These dowels pass completely through the form and rest on the table top giving them the same reference plane as the guitar sides.

The third dowel hole is drilled on the center line joint near the neck joint area. This dowel must be adjustable up and down to account

for the difference in the height of the sides at the neck and tail. By unclamping the form by this dowel it can be adjusted then the

clamp is re closed to hold the setting.

Step 1: Mark the desired height at the head and tail on the guitar center line.

Step 2: Adjust the tracking pencil so that when it is held against the suspended form it will touch the same point marked on the tail end.

Step 3: Raise or lower the adjustable dowel until the pencil point matches the mark at the neck end.

Repeat Step 2 and Step 3 until the pencil exactly hits both marks.

Step 4: Holding the tracking pencil against the concave dish mark the sides all the way around.

Step 5: Mark the head and tail blocks on the inside of the guitar also as this will help hold the correct sawing angle when cutting these blocks.

Step 6: Saw the sides and blocks about .050" above the line this will leave room for sanding and correcting the radius.

( Or set the pencil to mark a second line .050" above the desired line. Use that for the cut line leaving the first line as a guide for sanding.)

Step 7: Glue in the kerfing and sand to match the contour of the dish.

The radius of curvature marked is slightly less than the radius of the form by an amount equal to the height setting of the Pencil.

That height was 2.5" on the example of a 15' or 180" radius dish so the error is 2.5 out of 180 or about 1.4%

By choosing shorter support dowels and pencil height settings this error is reduced proportionally.

The tracking pencil is adjustable and held by the tight fit of the dowel in the hole. The three feet are nickel upholstery tacks.

The lead holder is stolen from my drafting compass.

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