The violin making manual

Depending on your judgement and the violin you are copying decide what the actual width of the saddle will be. Usually, its width is between 32-35 mm.
Take a compass, measure a half of that width and make marks on both sides of the centerline as in Fig. 1.
Make two incisions a and b, see Fig. 1. Using a straightedge make a line c at right angle to the centerline connecting them. The same as with the neck mortice.
Remove the material in the same way as in the neck mortice, down to the ribstock.

For illustration, in Fig. 2, you can see the diagram of a finished saddle. View a / front, b / side, c / top.

Prepare a block of ebony, about 8 x 7 x 35 mm.
Choose what will become the back of the saddle in contact with the mortice in the plate and make those two sides at right angles to each other, the 8 mm side going up.
Cut the ebony block to the correct length so that it fits the mortice easily. Remember that later on, as the top plate shrinks in dry weather, this block of ebony shrinks much less in extreme cases causing the top plate to split. So the fit must not be too tight, the saddle should fall out if you hold the body upside down.
Put the block in the mortice, make sure everything fits perfectly. If it does, run a marker around its front and sides to mark the level of the top plate, see the dashed line in Fig. 3.
Plane the front side of the saddle down to the marked level at the angle of about 60 degrees. See the side view of the saddle in Fig. 3.
On the top of the saddle, mark the center c and from it, using a compass, mark two lines a and b, 9 mm from the center on both sides. See Fig. 4.
From those two marks, down to the lines scribed in 4, create on both sides shallow slopes as in Fig. 5 using a knife.
Put the saddle back in the mortice and make sure the front and sides run down smoothly to the plate`s level.
Glue in this position using medium hide glue.

When dry, using a file, on the back of the saddle, recreate the outline of the plate. Make the bottom of the back of the saddle round so that it naturally continues the overhang.
Decide on the height of the saddle. Normally its about 3 mm but with higher arches it can be slightly more.
File the top down to the chosen height.
Connect the newly defined top with the back with a rounded slope, see Fig. 6.
Finish the surfaces using fine abrasive paper. Do not at the same time loose much of the the crispness.

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