How to tackle this tricky shape?

[jhiker]

Any thoughts on how best to tackle this? I have a 2" OD tube with an elliptical hole through it.
Around the 2" OD tube is a 1/8"OD cooling pipe 'loop' which is brazed to it. The cooling loop has to go round the elliptical hole (preferably at both sides) - seems I have to curve it in two directions - a loft of some kind? Or a complex 3D sketch?
In real life it looks like this.

 

[DavidJ]

Jeff - I'd continue the helical pipe paths until the point where they should deviate.

Create some temporary geometry that can be suppressed later - on a plane above the hole, sketch the projected outline of the path around the hole, thin extrude that sketch down through the part.

Open a 3D sketch, project to sketch the edge where the thin extrude meets your 2" tube. Close the 3d sketch. Suppress the thin extrude.

Use the 3D sketch as the path for a sweep, project the end of the cooling pipe as the profile to be swept.

Same method as shown for the old 'worm track' problem some years ago.

You may have to fiddle with placement to get the sweep path to contact your profile to be swept.

 

[bigseb]

View attachment 32877 View attachment 32878 View attachment 32879 View attachment 32880 View attachment 32881
Any thoughts on how best to tackle this? I have a 2" OD tube with an elliptical hole through it.
Around the 2" OD tube is a 1/8"OD cooling pipe 'loop' which is brazed to it. The cooling loop has to go round the elliptical hole (preferably at both sides) - seems I have to curve it in two directions - a loft of some kind? Or a complex 3D sketch?
View attachment 32882 In real life it looks like this.

 

[Markaj]

I have to ask.....what is it?!

 

[jhiker]

I have to ask.....what is it?!

Ha! - it's a type of mass spectrometer. There's a 'hot' source and an electron multiplier detector inside the 2" tube and the coiled pipes have cold water flowing through to keep the source from getting too hot.