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When free building (moldless) what is the technique used to get the radius on the kerf linings after gluing ?

J

For the top, dentellones. Sand an angle into the tops of them individually. The perimeter itself is flat, but the dentellones still help support the dome. More angle on the ones around the waist where the top's arch has to stretch down the most to reach the flat plane, and less around the tail block and wide part of the lower bout. Above the waist, especially right as you approach the head block, it depends on how much the top of the block is angled to match the neck angle.

For the back, kerfed linings and a finger plane. I glue the sides on at constant width, then taper them from tail block to head block by saw/block plane/whatever, and work it until the rim is all in the same plane (lays flay on the workbench with minimal gaps anywhere around the edge), but also about 1/8" above the blocks. Mark a reference line all the way around the sides about 1/8" down from the edge, and finger plane the approximate contours of a domed perimeter (lowest at the blocks and outer limits of the lower bout, highest at the waist). Then glue kerfed linings, and more finger plane work to angle their tops to the dome shape. Then it's on to final voicing of the top, now that its perimeter is constrained so you can really hear it

I glue the back on with spool clamps, so it conforms to any imperfections in the perimeter shape. Also interesting to clamp on the back and then tap on the plates to tune the top/back coupling effect (long echo when tapped). Although I haven't figured out if this actually helps anything, since the effect comes and goes throughout the rest of the build process. For one thing, the tap tone is way lower pitched than it is after gluing the back and removing the clamps, because the clamps are so heavy (mass loaded sides ). For another, the bridge isn't glued on yet and that drops the top quite a bit. Bindings might change it too.