Connecting spiral and sketches to path

Look in help under Composite Curve.

HTH, Muggs

I usually don't do entire springs as a single path. Many reasons for this.

Usually I sketch the ends' positions in a master sketch that controls the helix. I make the helix sweep, then the ends as separate features. I use spherical revolves to fill the gaps between ends and helix.

I have always modelled torsion spring arms on planes normal to spring body axis. I have tinkered with modelling springs with ends that ome off tangent to the coil direction (not normal to main body axis). This falls apart after the first bend if there are bends in the end arms.

I have some torsion spring samples at

TorsionSpringByTheTick.zip Hinge.zip (includes barrel-shaped torsion spring with multiple positions)

There are several spring models on 3DCC under User Library/Hardware/Springs. I have used several of them. I would think you would find one that at least gets you most of the way there.

WT

Draw all the elements you just mentioned, the two flat ends and the helix.

open a 3D sketch and use Convert Entities to bring them into the 3D sketch

use Split Entities (Tools, Sketch Tools, Split Entities) to "trim" both the planar ends and the helical sketch entity back so you can transition smoothly between them

turn the unwanted sections of the sketch entities into reference geometry

draw a two point spline between the trimmed back ends of the helix and the flat, and assign tangency or equal curvature to the ends.

exit the 3d sketch and make it the path for a sweep.

here's an example:

Not quite your problem - but it should give you an idea on general solutions.

I did, but it didn't work. It wouldn't let me join the 2D sketches of the end pieces to the spiral.

I've now found out why: I can only join 3D sketches to the spiral. So I made a couple of 3D "glue" sketches, each with a spline between the straight end pieces and the spiral.

Speaking of 3D sketches: Boy, do I hate them. All I wanted to do was, in straight Top view, to draw a spline, merge its end points to existing curves (both in the Top plane), make the spline tangential to those and be done with it. Fiddle, fiddle, fiddle. Red curves all over the place. Then I rotate the model a bit to see what's going on, and I see that there is a mile-long loop of spline jutting into outer space along Y. Why is that?

--Daniel