# How to 3d fillet to a point

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I have a cube that I need to fillet but the fillets must merge.

the left to centre edge/fillet is a constant curve. the same with the bottom to centre edge/fillet. but the edge from centre to the right starts at a radius and goes into a point at the corner.

What command or sequence of commands can create this? Note, the point where the 3 fillets meet must all curve gently.

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Consider creating a cone with a base radius equal to the full fillet radius and a height equal to the leg length minus the radius, union a sphere with at the base with radius equal to the fillet.

Now use this to "drill" into another solid that has had your original box subtracted from. Now you've got a solid that you can subtract from your cube.

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My feeble attempt yielded this result. Best I can do at the moment.

I used a different method than what is described in the above post.

I'd give it another try but I'm working today in an office where the AC unit died and it feels like I'm cadding in a rain forest. LOL

Edited by ReMark

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tmd_63: Did you ever solve your problem? If so, what method did you use?

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ReMark,

Your picture looks perfect. How did you create that?

I have been trying but I keep getting plane face errors. I want to use this method to make a fillet from 3 joining 3d walls.

The 3d walls have one wall which is a wedge shape and therefore needs to have the fillet changing from a 3mm in the corner to zero where the fillet meets the floor. SO my idea was to use this shape and 3d subtract from a 3d block to make the fillets.

I have not been having much luck with the revolve of the cone because the cone is not aligned to the normal XYZ axis. I dont have inventor to be able to quickly a variable fillet and I am seriously thinking of using Blender instead to create the shape I need instead of AutoCAD.

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Here is a depiction of the sequence I followed. I initially divided the 3D model into two parts. The front part was relatively simple as it only required the use of the fillet command. As for the back part the method I used basically relied on lofting one-quarter of a circle (at front corner) and a very, very small right angle (at the rear corner) to create a surface used to slice the edge of the box off. Understand?

2Dwireframe visual style. Isometric view.

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Use the FILLETEDGE command. It's specific to 3D, while FILLET does work, but is more specific to 2D. With FILLETEDGE, you can select multiple edges before you complete the command, as well as having Chain and Loop options. Just make sure your radius is logically possible and it'll work, especially on simple geometry like a box. Trying it on complex geometry, say, a guitar body, will make you pull your hair out. Trust me I know.

-TZ

*EDIT*

Demonstration video attached:

http://screencast.com/t/T8QY4I0UY3

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Hi Tannar,

Great video, but this does not complete the action required. One of the edges goes from a 3mm fillet at the rounded corner to a 0mm fillet at the other end. Basically it is a variable fillet that changes radii from one end to the other. It looks like a cone has been placed along the edge as ReMark has shown.

Hi ReMark,

I am still unclear as to how the lofting of the quarter circle worked?? What does the very very small right angle do?

You create an arc that is the same as the quarter circle, type loft, select the arc..... then what did you do? This is where I get lost.

Regards

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I did a loft between the quarter circle and the small right angle and used the resultant surface that was created to slice off the squared corner of the box. Very simple...very direct.

Someone here can possibly demo the technique and post a drawing. Unfortunately I can't do that at the moment from 30,000 feet in the air. My arms aren't long enough.