Round hem unexpected behaviour?

[PremTM]

Hi, I don't have much experience with sheet metal parts, but I think there's a bug with a round type of hem feature.

I'm providing a simple part with a single hem feature. First thing to notice is that you can't add a flange to the end of this hem, so I thought I'd add a contour flange. I've addad a single line and constrained it perpendicular to the end of the hem and here's another unexpected behaviour:

If you dimension the line first and then constrain it - it works fine. If you first constrain it and then dimension it, it flips 180 deg. When you change its length from current length to anything more than that - it flips.

Now to the last weird thing - when you have the sketch for contour flange (in this case a straight line) and you use the tool you're unable to create the flange untill you trick inventor into thinking it's a separate solid. When you switch between "Join" and "New solid" options it starts to recognize the feature and works just fine from that point onwards.

I may be using the tool in an unintended way, but it's the last part that I've listed that convinces me it's a bug plus this is the only type of hem, which behaves this way.

Release 2019.4.2, build 330 64bit.

Best regards,

Tom.

[PremTM]

Actually it seems that's how Inventor treats all round objects in SM environment, so I'm guessing this is not the intended way of doing it? The proper way would be to create a sketch with the outline of the part  in the "as folded" state and use contour flange in all(most) cases of objects that do not terminate at round piece, right?

[IgorMir]

Hi;

Here is a screen shot of your part. Contour flange works fine. Instead of specifying a length of it just pick the long edge of the part.

Cheers,

Igor.

[PremTM]

I triple checked that before posting...turns out that once I've returned to it now after session contour flange works fine and doesn't present any of those malfunctions. Apparently closing and reopening inventor when you observe weird things happen might just fix it for you, got to write that down...