Peter Coombe Mandolins and Guitars
Carving the top
This is how it all starts out, two wedges of Spruce. In this case it is wedges of European Spruce from Switzerland.
The thick edge of the wedges are first planed perfectly flat.
The wood surfaces are warmed with a heat gun.
Hot hide glue.
Hot hide glue is brushed on one surface.
The wedges are rubbed together until the glue takes hold and then left to dry at least 24 hours.
The back of the glued Spruce wedges are planed flat.
The outline of the mandolin top is drawn on the back using a template.
The outline of the top is cut out on the bandsaw.
Here is the top cut out to shape.
The edge is marked to 5mm..
The position of the fingerboard is marked.
Now is ready for carving.
The top is rough carved with the rotary chisel.
Here it is after finishing the rough carving. This only takes about 15 minutes. Cleaning up the mess usually takes longer.
The top is then shaped with finger planes.
Here it is after being shaped with the finger planes. It is now ready for sanding.
The marks of the finger planes are smoothed out with a sanding disk in a power drill.
Final shape is checked with a template.
Final shaping and smoothing is done by hand with sandpaper.
Feel for lumps and correct if there are any lumps or ridges.
Also check that the bridge will fit easily.
Make sure there is a smooth arch.
Everything is OK, so give the top a light coat of blonde shellac. The shellac will protect the top from greasy finger marks and glue marks.
We are ready to rough carve the inside of the top, but first mark around the edge where the ribs and linings will glue to the top. This must area must not be carved.
Now we need to drill some holes in the underside of the top to indicate how deep to carve. First set the drill press up.
Drill the depth holes.
Now the depth holes have been drilled, we can rough carve the underside of the top with the rotary chisel.
Carving with the rotary chisel is a really messy business.
Rough carving finished. Only took 10 minutes. The cleanup took longer than the carving
Now the inside of the top is shaped with finger planes.
Here it is after being shaped with the finger planes.
Now mark the soundhole.
Over to the drillpress and drill a pilot hole.
Cut out the soundhole on the fretsaw.
Here the soundhole has just been cut out. Note that it is not quite a smooth oval shape just yet.
Smooth out the soundhole with the Dremel fitted with a sanding drum.
Oval hole mandolins have the fingerboard glued to the top, so we need to plane an angle equal to the angle of the neck into the top.
I use a small template cut to the neck angle (4.5deg) and a spirit level to check that the angle is correct. The bench is also checked that it is level beforehand.
The angle also needs to be level horizontally.
The bridge height also needs to be right. This will give a final bridge height of around 19 or 20 mm, which is about right.
Now that all the angles are correct - 4.5 deg slope, horizontal, and correct bridge height, the excess wood is removed around the fingerboard with fingerplanes.
The final step is to hand sand around the fingerboard area.
Now finished. Ready for the next step, installing the soundhole trim.