Trying to make a tapered manifold using sweep on a coil that has a radius

[j_payton59]

I'm making a manifold for a wind turbine that is similar in shape to a spiral rams horn. To produce a coil using the coil tool give a straight axis, and I'm looking for radial axis like as if the rams horn was formed inside a torus. The actual shape starts as a rectangle then tapers in volume at other end.

[etfrench]

Loft with the spiral as the path:

I projected the edge of a flat spiral to a sketch to use as the rail.  If you use a coil, then you'll need to use a 3d sketch and project the edge of the coil.

[jasonhomrighaus]

Try this approach, Should work with spirals or coils.  The shell command does not seem to play well with the shape but this cutout method worked fairly well.

Let me know if any questions

Rams Horn 

[jasonhomrighaus]

 

[j_payton59]

[etfrench]

Is that the negative of the form?

[j_payton59]

There is a foam model that was made and can show the manifold as the channel around a 1/6th section of a torus. The channel is the manifold without the outside cover

[j_payton59]

What is the method?

[jasonhomrighaus]

you can look at the timeline and see the steps.  now the I see your model I will do one that shows that.

[j_payton59]

Interesting. The axis of your model is straight and the manifold is a radial axis. The ends your model would need to be on same plane but away from each other, like a coil

[jasonhomrighaus]

ore what you had in mind?  Its a little hard to tell if the spiral just tapers in the long axis or if it is also narrowing in the radial direction

[jasonhomrighaus]

Let me know on that model if it looks right or needs more refinement.  I can set up steps for you once I've got it right

[j_payton59]

That is very close. The taper is both the width of the channel that starts at 55mm going to 25mm, the depth is 10 and reduces to 8 by the end. The spiral goes 540°, or 1.5 turns. I can't tell from the render if the axis is straight or radial. I'm only looking for the channel and the foam was diy modeling, and the channel is enclosed, a manifold for air to pass to a turbine.

[j_payton59]

It does appear that the render is a cylinder. That's where I'm hung up. A cylinder has straight axis. This manifold uses a torus section, radial axis. 

[jasonhomrighaus]

The main body there is a cylinder and the channel does taper in the axial direction(ie the channel gets shallower.  I did not include a taper width wise but now that I have some details I can work that out and then share a methodology for you

can you tell me the other major dimensions ie length and diameter?

[j_payton59]

The model diameter is 70mm and about 150mm long. This pic shows the tangent of the manifold that is about 55mm x 0mm and progressing to 55x10mm. This area is where a rectangular opening allows air into manifold

[jasonhomrighaus]

Ok so I was able to get the taper and shape.  it's not perfect but its pretty close.  Ive just seen your additional photos.  Would this bee made in a flexible material or would it need to be shaped to match the curve or your torus out of hard material?

[j_payton59]

That render is very good for a straight axis. Yes, it will need to conform to a torus. I'm curious how to do it if possible. I've tried using an arc sketch 150mm at 550 radius. Then installed 10 planes along path and from those planes sketched a 35mm line in each plane to correspond to a spiral. Then on the end of each line a rectangle sketch that started at 55x10mm and transition to 30x8mm. Ten planes isn't enough. The result was not able to conform to 70mm in diameter between planes. I was hoping an actual method existed to do this render otherwise I'll re try my 1st attempt with 60 planes

[j_payton59]

I meant 225 radius not 550 diameter

[j_payton59]

The diameter is 550