# Creating half-cylinder walls in a mesh

I am new to blender and am having trouble inserting "inward beveling" the walls of my mesh. I am using 2.91 of Blender.

I have the walls defined - below:

I am using cylinders as templates to create the arc I want in the primary cube. I want to now "cut out" the cylinders and create new walls aligned to the edge of the cylinders where they intersect and bevel inward on the primary cube. Then I need to add some thickness to those walls.

Here are images from the top of the primary cube and bottom so you can see the vertex.

I have tried the boolean modifier but it does not create the inner wall - it just removes from the faces that the cylinder intersects with on the primary cube. And I am having some issue there where it's not delete anything from the top face (the one without the extrusion). It might be I need to add a grid fill to create more faces.

Any help is appreciated.

• Please consider seeing a tutorial on Proportional Edit. With a well populated mesh you can edit with a spherical form. There are also Boolean operations that can cut subtract one mesh with another. – atomicbezierslinger Dec 28 '20 at 23:32

I'm not sure this is what you want but here is a try, you can use a Boolean with a closed shape (put the Boolean above the Mirror modifier, choose Solver > Fast):

Then apply the modifiers, delete the bottom face (you'll probably need to clean the topology if you plan to add bevels or use a Subdivision Surface, etc), use a Solidify modifier to give thickness to your walls (enable the modifier's Even Thickness option):

Another solution using vertex bevel.

1. Add an edge top and bottom (for now you can F a temporary face for your object, it will be deleted later)

2. Select the vertices that define the edges and press Ctrl + Shift + B followed by P to change the profile.

1. Hide everything except the bevel you just created with H

2. Alt + Shift select and use Bridge Edge Loops to complete the shape on each side

• Oh, this is pretty cool :). Always wondered what's the use of vertex bevel... – Jachym Michal Dec 29 '20 at 9:07
• with vertex bevels you can create round holes, or round corners, etc – moonboots Dec 29 '20 at 14:34
• Wow - I never would have figured that one out. I ended up using Moonboots approach -but will try this one as well. – seahawk2000 Dec 29 '20 at 16:16
• Bevel has alot of possibilities using the profile tools (especially new custom profiles). You should accept @moonboots answer if that answer was the best one for your problem. – Timaroberts Dec 29 '20 at 16:29

As someone who tries to avoid booleans, as they result in irregular topology most of the time, I would do this operation with Proportional Editing

Create a few loop cuts, select the edges in the middle, enable proportional editing in Sphere Falloff mode. Then scale on one axis only (in this case, to scale only on the $$Y$$ axis, press S+Y) and move the mouse. To control the influence of proportional editing (and thus the radius) use the scroll wheel on the mouse.