Once the soundboards are joined the first act is to install the oval trim and cut the sound hole.
That is done with a router following the edge of this 1/4 inch thick acrylic jig.
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Now that the oval slots are cut it is time to bend the 'rope' purpling. Note that the heat of the hot pipe has separated one of the edges. that's a good thing, makes it easier to bend into the slot.
Carefully bend it around and tap it into the slot
And here is the result, three nice soundboards ready to be thinned down to playing thickness on the sander.