Move face on curve variances

graham_lock

Hi,

Referencing the images below I'm using Move Face to move the upper curved face inwards.

The result I need is shown in the second image, however when a certain move offset is reached - dependant on the curve parameters - I get the results in the third image.

Is there a way of achieving the second image results regardless of face offset?

My test document is here:

https://cad.onshape.com/documents/3a46cada79081deba2804826/w/2c75ec5ed60c76a8b65782f8/e/beadee1e1409961cbbb94dac

Any help appreciated.

martin_kopplow

This is a thing that you should solve in your sketch. You specified a tangent curve in your sketch and so the software, believing this is your very important design intent, tries to keep the tangency as far as possible, while fulfilling your wish at the same time. That can't work out right outside very narrow margins. If you want a step there, sketch a step.

graham_lock

Thank you.

In my actual project the curved parts are generated via intersection curves.

The use case is a model aircraft fuselage where a skin is used as an outline from which to create half formers along its length. The indented steps are used to accommodate sheeting on given sections. The formers are generated by a custom FS.

Does this suggest any other way of achieving what I'm looking for without sketches?

I have updated my test document to better show what I'm trying to achieve.

EvanReese

I'm not seeing this effect in your document. Am I doing this right?

graham_lock

That's interesting!

I've just re-tried here and the problem still exists.

Just to confirm doc:

https://cad.onshape.com/documents/3a46cada79081deba2804826/w/2c75ec5ed60c76a8b65782f8/e/beadee1e1409961cbbb94dac