Twist pipe

[Britt007]

Hi,

I'm trying to twist a pipe to match the internal helicoid, In the attached picture I've moved the helicoid to the left for reference.

The problem is using a twist modifier I can't control the gap between the twists or the angle of the twist up the pipe.

I'm trying to mirror the helicoid so the pipe will bulge around the helicoid, any advice would be greatly appreciated, thanks.

Kevin.

 

[ZooHead]

Not sure if this is what you're looking for.

 

[Britt007]

Not sure if this is what you're looking for.

View attachment 39391

Hi,
That's exactly the effect I'm after but on the pipe I've made, so there are no gaps and with the bends intact.

 

[ZooHead]

You have a circumference of 64 polygons, so I start with a helix at 64 sections 0 to 360 degrees.
Set the set the radii according to the diameter of the pipe.

Take the number of turns you want and multiply the 360 Angle End by that.
Then do the same for the 64 Sections plus 1. Always add one at the end so all vertices line up.

I'll let you figure out how to set the Height.

I hope this helps you along, let me know if you need more guidance.

 

[Helmut]

Whilst an object like the one below is possible, it seems of questionable use. In the moment the helicoid in the centre rotates there will be wide annular gaps between the screw and the pipe. You will not be able to use this as an Archimedes screw for hydraulic displacement.
Of course, it is possible that I misunderstand the purpose of this apparatus.

 

[Britt007]

Not sure if this is what you're looking for.

View attachment 39391

Hi,
That's exactly the effect I'm after but on the pipe I've made, so there are no gaps and with the bends intact.

You have a circumference of 64 polygons, so I start with a helix at 64 sections 0 to 360 degrees.
Set the set the radii according to the diameter of the pipe.

Take the number of turns you want and multiply the 360 Angle End by that.
Then do the same for the 64 Sections plus 1. Always add one at the end so all vertices line up.

I'll let you figure out how to set the Height.

I hope this helps you along, let me know if you need more guidance.

View attachment 39394

Thanks for your help much appreciated, what I can't work out is how you got it to bulge as it extrudes up the helix. or am I missing something simple?

 

[Britt007]

Not sure if this is what you're looking for.

View attachment 39391

Hi,
That's exactly the effect I'm after but on the pipe I've made, so there are no gaps and with the bends intact.

You have a circumference of 64 polygons, so I start with a helix at 64 sections 0 to 360 degrees.
Set the set the radii according to the diameter of the pipe.

Take the number of turns you want and multiply the 360 Angle End by that.
Then do the same for the 64 Sections plus 1. Always add one at the end so all vertices line up.

I'll let you figure out how to set the Height.

I hope this helps you along, let me know if you need more guidance.

View attachment 39394

Thanks for your help much appreciated, what I can't work out is how you got it to bulge as it extrudes up the helix. or am I missing something simple?

Whilst an object like the one below is possible, it seems of questionable use. In the moment the helicoid in the centre rotates there will be wide annular gaps between the screw and the pipe. You will not be able to use this as an Archimedes screw for hydraulic displacement.
Of course, it is possible that I misunderstand the purpose of this apparatus.

Hi Helmut, thanks for the input, I'm just messing around with ideas at the moment to force the flow of liquid to the outer walls as it passes through the pipework for heat transfer from the pipe to the outer surrounding water.

 

[Helmut]

Hi Britt007
* For a bulge on a helix-based tube you need to experiment with a sweep (instead of an extrusion). The axis of the sweep will be a helix - equal to the outer helix of the helicoid - whilst the cross-section is a semi-circle.
Warning: This is a bit fiddley and time consuming, as
1 the cross-section of the pipe gets adjusted to the ascent at the 1st segment of the helix
2 you need to rotate the sweep to get a proper start > end transition (in my trivial experiment 222°)
I doubt that you can get a clean topology by using parametric objects.