Making a box with a design

[WillAdams (William Adams (Carbide 3D))]

Another option would be to use a suitable corner roundover tool:

Using unsupported tooling in Carbide Create: Roundover / Cove / Radius bits

These are usually used in routers for decorative effects in wood: https://www.whitesiderouterbits.com/products/1570 but they are potentially useful for joinery: They are also useful for rounding off parts to allow rotary motion as for a hinged lid. Unfortunately, Carbide Create does not support this endmill geometry — but using the new support for previewing a V endmill when used in a No Offset Contour toolpath, it should be possible to preview them w/ confidence by stacking a series o…

it would still require a bit of filing, or machining a void.