Compound radius - how's it done in larger factories?

[Anders]

I've seen both routing and sanding DIY jigs, but I'd like to know a couple of things:

1. How is it done at Jackson for example?

2. If done with a routing or a belt sanding jig, how is the sanding up through finer grits done to avoid messing up the radius?

3. Does anyone have a factory tour photo/video that shows a compound radius being done by any of the larger manufacturers?

[Aso]

Sully has a video talking about making a jig for creating compound radius (https://www.youtube.com/watch?v=hwEVJC78IRM). I would think in the Jackson custom shop it would similar process. The Custom shop isn't more than 5-6 luthiers I believe.

[sully]

You can CNC them pretty quickly, and there are also swings that hang over belt sanders. I've got one, but really need to set it up.

[Anders]

Thanks guys!

Sully - When fretboards are CNC'd that way, don't they need anymore sanding? Or perhaps they finish them off on the belt sanders? But what grit do they finish at? It feels like sanding belts aren't available in higher grits..?

[sully]

You definitely still need to sand the cutter marks out of the board. Depending on how fine they go, you can hand sand them out pretty quickly.

[Anders]

Thanks Sully! Is that done with sand paper "by hand" only? Or together with a flat sanding block following the "cone"?