Select proportional edit mode, connected, linear falloff.
Move the selected vertex along the Z axis.With the influence radius set to cover part of the circle, it pulls out the curve behind the dragged vertex as you’d expect. Expand the radius over the entire circle, however, and instead of pulling the curve into a sort of helical shape as you’d (well, I’d ) expect, it pulls both ends of the curve exactly as though it were in regular (non-connected) PE mode, or as though the circle were still closed.
Is this the way it’s supposed to behave? If so, how can I stretch this (or a) curve into the loose helical form I’m trying for?
You can use the Screw modeling tool to make a loose helix as follow (apologies for lack of screenshots):
Delete the default cube. Go into Front view with Numpad 1 (screw tool only works in Front view). Add a plane. Delete 2 of the vertices so you end up with a vertical edge. Select these 2 vertices with A-key. Shift-S->Cursor to selection.
Deselect the 2 vertices and staying in Edit mode, Ctrl-LMB to create a single, unconnected vertex where you want your helix to start. Select all with A-key. In the Editing panels (F9) click Mesh Tools -> Screw.
The tool will create 2 meshes, one is your helix and the other the extruded “guide line.” Use L-key to select the unwanted guide line and delete its vertices.
Here is the wiki manual page on Screw tool. Play around with the Degree, Steps, and Turns values to make different types of helices. If you change the angle and/or size of the guide edge you can make tapered helices etc. You’re also not limited to screwing single vertices; you could start with a circle for example and make a coiled hose. Have fun.
Well, you should be able to achieve a reasonable single level helix.
You are certain the circle of influence isn’t covering the endpoint you’re trying to anchor? That would be my first thought. To adjust the influence use the middle mouse wheel. After you’ve turned on Proportional editing, Grab a vertex point and then, while still in grab mode, scroll the mouse wheel up to decrease the influence until you can see the circle.
Also you can adjust the type of falloff so that the edge of the circle of influence has a lesser degree of movement. Next to the orange circle that lights up when you turn on Proportional Editing is a curve on a graph icon. Click that icon and you can select the type of falloff.
Falloff is influenced by the location of Rotation/Scaling Pivot. If you’ve slected the Cursor as a pivot, the falloff will behave differently than if you’ve selected the default of Bounding Box Center.
Finally there are two types of Proportional editing. Inclusive and Connected. By clicking on the O icon you can select.
) expect, it pulls both ends of the curve exactly as though it were in regular (non-connected) PE mode, or as though the circle were still closed.