how do i make this in a box?

how big is the cube, and is it just that face or is the curve go all the way to the other side?

the curve should go all the way through the other side…
doesent matter how big it is…it could be big or small…

-- hrvoje

You form those corners with a drill.
You round it out with a spindle sander.
You trim those corners with a router.

Just 3 ways.

:ee

-- No piece is cut too short. It was meant for a smaller project.

This is just my wild thought.
There are 2 possible ways; 1) Prepare the 4 box sides oversize the final thickness. Using the Dish Cutter router bit remove the stock on the face the board to get the final thickness leaving the 2 sides of the board uncut. Rip it on the TS with the blade tillts 45 degree. Of course it’s not easy.

2) Prepare the 4 sides of the box undersize of the final width of the box. Prepare 4 sticks from the same wood species. If your final box side is 3/4”, then you need at least 1” thick stick to be used to joint the four corners of the box. Profile one corner of these sticks using the appropriate radius of Core Box router bit and and dry fit.

It could be easier to understand if I could use some drawings or Sketchup.

Core Box router bit – http://www.mlcswoodworking.com/shopsite_sc/store/html/smarthtml/pages/bt_core.html
Dish Cutter router bit -
http://www.mlcswoodworking.com/shopsite_sc/store/html/smarthtml/pages/bt_sign.html

-- masrol, kuala lumpur, MY.

Of course, the most obvious answer would be that you usually see this kind of corner on a bandsawn box, where you would be starting with a solid block of wood and cutting out the interior.

-- Charlie M. "Woodworking - patience = firewood"

yes but if i want a shelf which is deep about 20-30 cm i wouldnt be able to bandsaw that!?

-- hrvoje