Dissable Automatic Reliefs When Converting to Sheet Metal

[MikeOBrien]

Hello fellow users,


I am trying to create flat profiles for some swept boxed rails that we use to create frame rails for custom tailored cars. We do not mandrel bent existing box tubing, but cut out all four sections with a CNC plasma and tig weld them together. This allows us to be extreemly creative and produce profiles that are strong and very visually pleasing to the higher market customers we serve. (No wrinkles and smooth transitions)


I have been using sweeps mainly to assure that I have a gaussian surface to use for creating a sheet metal part. I extrude a profile as such:

I then convert it to a sheet metal part so that I can flatten the part to create the templeate we need to cut from our plasma. The problem is that when I do, I cannot seem to avoid the relief cuts that solidworks automatically produces in each sweep:

Here are four pieces assembled for a visual reference:

I have been getting by simply by filling the reliefs with material before I export them to our plasma tech, but this process is time wasted and slows down our fork flow on complex models. (The example I am showing here is very simple)

My main question is this: How can I dissable or get around the automated relief cuts in SolidWorks sheet metal? Is there another process that would be less time consuming and produce the same results. Remember, I don't really care to reassemble the parts bent into an assembly, I simply want to deconstruct a profile into it's flattened profile so we can then cut it out very accurately. This is the end goal:

Thanks for any help or suggestions,

-Mike



Mike O'Brien

Mechanical Engineer

The Roadster Shop,

http://www.roadstershop.com

 

[hititfaster]

It's a punt, and I haven't re-created the issue myself, but I think SW creates a relief only when under flange position, you pick the option of material inside, or material outside. If you pick bend outside, you don't get a relief.

That's got to be too simple to be right, but maybe worth a check!

 

[TheTick]

I hate auto relief. I usually set it to "tear" and then cut my own reliefs.

 

[MikeOBrien]

Thanks for the tip, but it did not work for me. I did however change my process which has had very favorable results on a majority of the simpler models I work with. I had been "creating" my profiles into sheet metal parts by following the sequence of Insert>Sheet Metal>Convert to Sheet Metal... This process left some of the larger reliefs in the simple geometry shown above. Playing with some other settings, I decided to try and simply bend the material by applying Insert>Sheet Metal>Bends to a planar face, and modifying no other settings. I can then un-suppress the "Process-Bends1" feature in my feature tree, and I get a flat profile of the bent component with no reliefs!

New operation looks as so in my feature tree:

The new "sheet metal" part with no reliefs:

Assembled:

Flattened:

I do still however still have issues with the reliefs on more complicated structures. Here is a quick example of a sweep that is offset in both the x and y axis, and the profile does not stay constant through the curve.

Note how there are still some smaller reliefs. I used my new process with general better results than before, but the reliefs are still in some complex parts. Her is the top rail piece flattened and a close up of the relief that is annoyingly automatically added.

If anyone has any other suggestions I am all ears. Is there any way to disable this automatic feature by adjusting a macro?

Thanks,
-Mike


Mike O'Brien

Mechanical Engineer

The Roadster Shop,

http://www.roadstershop.com

 

[CorBlimeyLimey]

Have you tried extruding the profiles as sheet metal parts, instead of converting them?