Split Body command splits along an infinite plane even though "Extend Splitting Tools" is not selected

[mailV2KPH]

I'm trying to model a simple shelving unit with mitred (45 degrees) joints in the corners. 

I'm trying to achieve this by splitting the body into 4 parts using the Spilt Body command with construction planes as splitting tools. The construction planes are not drawn as extending very far past the intended split, and do not touch any other part of the body. I have unchecked "Extend  Splitting Tools" in the command dialogue. But the split keeps extending and cutting into another part of the body along the same plane. There must be some way of limiting the extent of the split. 

I've attached as screenshot which shows an unwanted split in the vertical part of the cabinet in the same plane as the intend split in the top right corner. It's not that easy to see, but it's the horizontal black line about 1/3 of the way up on the left.

Can anyone help?

Thanks!

[jhackney1972]

Please attach your model.  Maybe a Surface Split is the answer but will need model to test. 

If you do not know how to attach your Fusion 360 model follow these easy steps. Open the model in Fusion 360, select the File menu, then Export and save as a F3D or F3Z file to your hard drive. Then use the Attachments section, of a forum post, to attach it.

[jeff_strater · Accepted solution]

construction planes are always considered infinite, regardless of their display size.  The "Extend Splitting tools" only applies when a surface body is used.  Instead of a construction plane, create a sketch on that plane, and draw a rectangle of the exact size you want to use as a splitting tool.  Then, use Boundary Patch to create a surface body from that rectangle, and use that as the splitting tool in Split Body.

[TheCADWhisperer · Accepted solution]

@mailV2KPH 

You can probably use a simple 2D sketch as the splitting tool.

No work planes needed.

No work surfaces needed.

[davebYYPCU]

Sketch must create at least 2 parts as the result, select both cutters in one Split body command.

Might help….

[mailV2KPH · Accepted solution]

Thank you!

[mailV2KPH]

Thanks John, that's really kind of you. I wouldn't be surprised if I've made a few other mistakes! The model is attached. 

Best,

Adam