Can't create a proper shell from a body

[bluepr0]

Hello,

I'm trying to replicate this boxes here https://www.thingiverse.com/thing:4812321

I was able to replicate the 1x1 box correctly as you can see in the attached screenshot. However when trying to do the 1x2 box I'm having trouble with the Shell command.

This is what I'm doing (attaching an steps.zip with the images)

1. Create a new sketch with the dimensions of the box

2. Extrude that box to the desired height

3. Create another sketch on the bottom plane with both squares that will hold into the grid

4. Now extrude those new squares from the sketch to get the basic shape of the box

5. At this point if I add a shell command and do a cut into the box, the geometry is correct. BUT I need chamfer for the 3d printing

6. So when I add a 1.5mm chamfer at 45º the geometry at the bottom of the wall it creates it's not correct (should be like on the screenshot I attached)

7. Just another view of the cut of the box + chamfer

If I first create the chamfer and then try to apply the shell command, then I get an error in the input geometry and it doesn't work. I've been trying a few different ideas but I honestly don't know how to make it work. If anyone can provide some light would be much appreciated.

Thanks a lot in advance!

[g-andresen]

Hi,

Please share the file.

File > export > save as f3d on local device  > attach it to the next post.

günther

[bluepr0]

Sure! thanks 

[g-andresen]

Hi,

is that what you want to achieve?

Screencast

günther

[bluepr0]

Umm not exactly, attaching the source file for the 1x1 box which has exactly the geometry I want. You will see there's 2 chamfers, one in the main box and a small one at the bottom of the squares

[g-andresen]

Hi,

I think this way you have the least problems.

günther

[bluepr0]

Umm I'm quite new with Fusion360 but as I'm analyzing the geometry with a section, it's not generating the one I'm looking for, sadly.

 vs what I need

 

[g-andresen]

Hi,

I did not use outer contours on the large box because they are not necessary for illustrating the split body process.
I also did not pay attention to dimensions in this example. You should already do that yourself. But you can see that the box can also be filled incompletely without boxes slipping.

günther

[bluepr0]

Thanks a lot, I'm still very new to fusion360 so not entirely sure about this, but I will try to get my mind around it. 

[bluepr0 · Accepted solution]

I was able to finally make it, I had to create an offset of the box dimension, create a rectangle to cut the offset in the middle and then I can properly extrude + use shell command. Later I added the fillet to the missing corners.

I'm still wondering why the original construction is not working with the shell command, as that's cleaner.

If anyone knows a better way please let me know. Thanks!