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This has been something I find really frustrating. What is the best way to make a concave carve. And to ensure that it transitions smoothly onto the "landing surface"?

CNC

Clay - that's convex - not concave.

Conor, I've used ballnose router bits, rat tailed files, sandpaper over round shapes, and even scrapers. It's a lot of work, and looks great if you are patient and careful.

_________________
"Act your age, not your shoe size" - Prince

Kutzall have a wide range of shapes and sizes.

Brent

Haha, thank you, that's helpful. Barring access to tools that require a large-ish investment, what's the best way to make a concave carve? Or to put it another way, how did people do it efficiently before the advent of the CNC machine?

Thanks, I thought about router bits, but I'm working with a finished body, and some different angles. While I could jig something up, doing it by hand seems simpler, and its a task that's come up several times lately and I've just not been happy with my methods.

Thanks Chris, I've never used ball nose router bits, but I've been working my way through your other suggestions. I don't mind a lot of work, and I have the patience, just wondering if I can refine my methods.

Conor, I am building a carved top archtop right now and have been using a little Ibex finger plane for all the inside of the top and the recurve. I did the trick of drilling contour lines as described in Bob Benedetto's book and use the little plane to connect the dots



My plane might be a little small for archtop guitars but I think it is perfect for a mandolin or maybe a violin.

You're already almost all the way there. Get your chisel super sharp so you can take ultra-fine shavings and just do it.

As others have said, a router bit with the proper profile is the way to do it quickly and precisely. Before routers, I suspect people simply avoided such features, or accepted the imperfect surfaces of hand carving.

Another potential approach would be to craft the object as two pieces and then glue together. That way the round-over could be done with files, and the bottom of the pocket would be part of the planed surface of the other piece.

https://www.eagleamerica.com/product/vp ... r-bit-sets

one of those with the top bearing could be used with a pattern/template to pull that off...3/16" is the smallest radius though

I want that inverted though. I don't like the rounded thing in this case, I'd rather the curve was concave. I feel like it willmake the transition flow better.

How did I forget about gouges? Used a lot on lathe work, but they would be fine for what you're doing, Conor. Many widths and radii available.

_________________
"Act your age, not your shoe size" - Prince

https://www.toolstoday.com/v-7995-160-70.html

something like that then...