How do I align these sheet metal flanges?

SledDriver

I've watched the preview video, which nicely evades this problem with an angled front to the box which means the flange is still a 90deg bend.

But what when the flange isn't 90deg to mate to a side flange?

I can't see how to do that.

https://cad.onshape.com/documents/af64487f57f7a4bc05a0b93d/w/8b56670c75204f5904e8c384/e/08a1e760702d942e57c6a666

Front and side flange do not align, nor will it even let me fudge the issue by manually tying in an angle in the table.

Pahl

Here I created the second flange feature. I unchecked Automatic miter and set the Bend angle.
Is that what you are trying to do?

SledDriver

Aha! Thanks for taking the trouble to do that again.

Yes that technique works well! Excellent stuff.

Ben_Misegades

There are certain aspects of that block that you've modeled in part studio 2 that aren't friendly for sheet metal model creation.

Have a look at my copy of what you've modeled. You can convert a lot of the faces into flanges, but not all, else you will have collisions in the flat pattern. That's likely why you're having conversion issues, not because of non-perpendicular faces.

https://cad.onshape.com/documents/381c3d41d72a24d86a6976e9/w/957eafa5cbb43538a75cb946/e/e1aa545b39cca16144f21a48

SledDriver

Yup that works.

Thanks for your feedback on this. I was deliberately trying to find limits with this example, as this is often a good way to further understand how it works.

This has been very helpful.

Cheers,

Pahl

Hi,

How about if you do each flange as a separate feature and then adjust the bend angles to what you want.

Pahl

Here I created the second flange feature. I unchecked Automatic miter and set the Bend angle.
Is that what you are trying to do?

SledDriver

Thanks, but I was rather expecting the bend angle to be calculated automatically for adjoining flanges. It may not always be so easy to compute the bend angle manually.

SledDriver

By way of example, can you match these flanges?

https://cad.onshape.com/documents/6a7e511a17384cab6b6eb2c6/w/c9f96754a5b1daa729668675/e/02fcdc6223fb7c3fbd3147f2

Pahl

I'm pretty new to all this yet and I'm certainly not a sheet metal guy but I took a shot at it.
I ended up making each flange a separate feature and shorting them a bit. Not sure if this is what you had in mind or not but take a look at it and let me know.
Maybe someone can share a better way with both of us.

https://cad.onshape.com/documents/58a10eadc320e20f8d2404a0/w/59081fd60efe1314f6ebe32d/e/a1900ea3742b11d7175d9cb4

SledDriver

Thanks for that. Your attempt simple proves my point that there seems to be a fundamental missing ability to align flanges which are not on basic geometry.

If you rotate your example appropriately, you can see the flanges are not aligned, and any attempt to make that piece would result in a very dodgy product indeed, exactly what you don't want from a quality cad solution.

Obviously its early days with this sheet metal stuff, but I was surprised it couldn't do this basic stuff. Also a little miffed that the example in the sheet metal intro video cleverly uses a blank which appears to be matching more complex geometry, but in fact it isn't - all the bends are still 90deg. Anything other than 90deg at this time and you run into problems it seems.

Ben_Misegades

I had a go at it, this will give you flanges exactly even with each other, though the method isn't my favorite:



https://cad.onshape.com/documents/58a5085c3522310f74b3672c/w/fcc1b92700c5fe64462b87fa/e/aa91312120ce4e79e88d116c

Pahl

@ben_misegades435

Nice job! I like how you went about it. Thanks for sharing.

SledDriver

Sorry, I'm late back to this discussion and it seems like the last example file is not longer available.

However, although it looks like you may have solved this example, yet again you have simplified the problem to a square cornered device with an angle only in one dimenstion.

My original problem was with compound angles. The corner was not 90deg, and the edges were not coplanar. This is a different and more difficult requirement.

Ben_Misegades

I quickly made a new document since I deleted the old one. This one has fewer 90 degree angles, though it doesn't really matter, this methodology doesn't really care if angles are perpendicular or not. Have a look, see if anything in that model is of use to you.

https://cad.onshape.com/documents/629b129b3b5a7ce649ca9bd0/w/4591d821b7e8a9cae8097097/e/31e5c797b254a46091d09d7f

SledDriver

Aha! Thanks for taking the trouble to do that again.

Yes that technique works well! Excellent stuff.

SledDriver

Just trying to find the limits with this now. This new model refuses to convert to sheet metal at all. It notably has drafted sides.

Surely there isn't a limit which says sheet metal sides have to be perpendicular to the base?

Have a look at Part Studio 2 in this document.

https://cad.onshape.com/documents/c37b593a65e7c4fdec03ec9e/w/15b4e318b4ad4dbe9ed63163/e/4d6e977099defe7891e99e3e

Ben_Misegades

There are certain aspects of that block that you've modeled in part studio 2 that aren't friendly for sheet metal model creation.

Have a look at my copy of what you've modeled. You can convert a lot of the faces into flanges, but not all, else you will have collisions in the flat pattern. That's likely why you're having conversion issues, not because of non-perpendicular faces.

https://cad.onshape.com/documents/381c3d41d72a24d86a6976e9/w/957eafa5cbb43538a75cb946/e/e1aa545b39cca16144f21a48

SledDriver

Yup that works.

Thanks for your feedback on this. I was deliberately trying to find limits with this example, as this is often a good way to further understand how it works.

This has been very helpful.

Cheers,