Rail doesn't touch all profiles?

[Anonymous]

Hey,

I'm pretty new to fusion 360. I'm trying to design (what I thought was) a fairly simple manifold that lofts from a rectangle to a circle at a 45 degree angle but I'm having a bit of a nightmare with it. 

I have the basic structure but I'm trying to create some guide rails for the loft. My first problem is that no many how many times I try to redraw it and check that all the pieces snap together. I still keep getting the message "Warning: The selected rail does not touch all of the profiles.". It's driving me crazy. I actually had it working once but now it wont. Any thoughts? 

The second problem will come next as I got past this point at one stage.. The other two sides as the sit on an angle, will be a 3D spline that curves in a couple of different angles. I manged to get the points snapped together using "3D Sketch" checkbox but I couldn't adjust the angles at all. I presume I'm going about this the wrong way?

Thanks

Stuart

[jeff_strater]

Use Project->Intersect in sketch, when editing the rail sketch, select the profile curves as input.  This will create a point at the exact place where the profile curves intersect the sketch plane.  Turn off other sketches, and make sure that you select this intersection point when creating the rail splines.  This will prevent you from seeing this error.

as to adjusting the angles of a 3D spline, use the Move command when editing the rail curve sketch to adjust the handles.  Simple drag in 3D does not work (and would not make sense), so you need a more precise way to control those spline handles in 3D.  Move is that way.

If you share the design here, you will get some more specific feedback on how to fix your problems.

[TheCADWhisperer]

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@Anonymous wrote:

Any thoughts? 

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Your sketches are blue?

Shouldn't they be black?

Can you File>Export your *.f3d file to your local drive and then Attach it here to a Reply?

[Anonymous]

Thanks for the response. I'm can't get the intersect to work 😞 
I've attached the file. Hopefully you can see what I've done wrong 🙂

[jeff_strater · Accepted solution]

There are a couple of issues here:  First, your rails seem to be fine - they do intersect the profiles precisely.  The problem comes in that "chain selection" is on by default.  Fusion tries to chain your rails to places they are not intended to go.  So, turn off chaining.  This means you will have to manually select all parts of your rails, but that is pretty easy.  Second, once you've done that, the loft becomes self-intersecting:

This, it turns out, is because the curvature of that rail on the right is too high.  You need to smooth that out.  To do that, edit the sketch, and use Move.  But, first, there seems to be a sketch constraint that is preventing this adjustment, so you first have to delete that.  At that point, the loft can be successfully made.  Here is a screencast:

[Anonymous]

Thank you so much!! Fantastic response! Helped me tremendously! 😄 No more headache haha