Lofting help

[jdpreynolds]

Hi

Wanting some help suggestions with lofting two profiles along a guide rail.  I am attempting to draw a brake lever arm from a Goods Wagon that has a complex 3D form.  I have drawn the front view as shown

 and a top view as shown

 I have succesfully added these two line together to form the complex curve with the 4 profiles asshown

 I have swept profile one (4'x1" Rectangle) along the first 18" of the complex curve as required by the drawings and have been able to loft the final curve (1 5/8"x5/8" slot shape) along the curve but have been unable to loft the centre section keep getting the error "the selected rail does not touch all of the profiles"

 I thought that I had all of the profiles on the rails as used "plane along path" to establish the profiles.

Any suggestion on the correct way to do this would be most appreciated

Many thanks

Julian

[jdpreynolds]

Here is the file I'm working on

[davebYYPCU · Accepted solution]

Works as a Centre line loft.

I did not use the intersect curve as the rail error is likely to be non tangent connection.

Instead, extrude a surface and split it with the other sketch.

Using the top edge of the surface as a rail was a Loft (at first attempt).

Fix yellow icons with Undo key, and figure why it went yellow.

Might Help....

[wersy]

That lines from edges of surfaces give better results than lines from intersection was told to me once by @TrippyLighting 
What is new to me is that in some cases only surface edges can be used as rails.

[TrippyLighting]

---

@wersy wrote:

That lines from edges of surfaces give better results than lines from intersection was told to me once by @TrippyLighting 
What is new to me is that in some cases only surface edges can be used as rails.

---

Curves (splines) or arbitrarily (non circular) curved edges that are projected into no parallel planes create that problem. Lines and in most circular edges usually don't cause a problem. But is is always a good idea to check the curvature of a projected curve or curved edge after an operation.

[billbedford · Accepted solution]

These things are a lot easier to do as interacting extrudes. 

[wersy]

---

@billbedford  schrieb:

These things are a lot easier to do as interacting extrudes. 

---

Great, it couldn't be simpler!
Actually, I am also a great friend of intersection of bodies.
In this case I have overlooked this possibility.

[jdpreynolds]

Thanks for all your replies and solutions to the problem I was having  I hadn't thought of intersecting extrudes which looks very easy will also go back and look at what was causing the error messages and see if i can get it to loft correctly 

Best regards

Julian

Christchurch

New Zealand

[davebYYPCU]

Double click the intersection curve, if it does not select the full length, make the surface edge.

Apparently the projection routine provides approximate,

but Loft is so finicky, it can’t handle approximate for anything.

Might help...