topic Sheet metal part with different bend radiuses in Fusion Design, Validate & Document Forum

Sheet metal part with different bend radiuses

rburnett — Mon, 13 Feb 2023 16:55:02 GMT

I am fabricating a part that has 3 bends done by v dies, and 3 bends have to have an apprx. 1" bend radius.

The developed blank size of the part is 10.865 x 36.127 out of 11ga mild steel.

The different bend radiuses have different k factors, and I cannot get the flat pattern in fusion correct.

What I need to make it correct is a k factor of .485 for the v die bends and .4 for the bigger 1" bend radiuses.

Is there a way to use separate sheet metal rules for the differing bend radiuses?

What would be the correct way to model this in fusion 360? I have not found any tutorials that were helpful for this situation.

Thanks,

Ryan

Re: Sheet metal part with different bend radiuses

jhackney1972 — Mon, 13 Feb 2023 19:40:04 GMT

You can have a different bend radius for any and all you Flanges and Bends. If you truly need a different K-Factor for different bends, that is where you are out of luck. The sheet metal body is one homogeneous piece of metal so it carries the same physical properties throughout the body so you can only have one K-Factor value per sheet metal body. Maybe an average value will get you by?

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Re: Sheet metal part with different bend radiuses

rburnett — Tue, 14 Feb 2023 13:11:36 GMT

Thanks for the help John that was very informative!

Upon further inspection of our sample, I realized I had the v die bend radiuses too big.

Once I fixed that, I manipulated the bigger radiuses until the flat size came out correct.

Thanks for the help!

Re: Sheet metal part with different bend radiuses

TheCADWhisperer — Tue, 14 Feb 2023 13:24:18 GMT

@rburnett wrote:
Is there a way to use separate sheet metal rules for the differing bend radiuses?

@rburnett

I am kind of surprised that I could not find a way to do this in Fusion 360.

However it looks like you sorted your issue.

In Autodesk Inventor Professional you can create as many rules as you need and then edit the k-factor bend-by-bend.

(You do have to model in such a way that bends of certain size/k-factor separate features.)

In the image I have a Bend with Default k-factor and two Bends with named k-factor "Large Radius".

It is quite valid to have different bend allowances for different radii in the same part.

The bend allowance is dependent on

1. Material Thickness

2. Bend Radius (inside)

3. Bend Angle

4. ~~(I have forgotten this one at the moment)~~. Material (Aluminum, steel, and grades of...)

and perhaps

5. Grain direction and other parameters.