please tell me how to blend the end of the thread (1/12 pitch) into the body of the pin. Thanks.

battiwallah

brian_brady

Any specific reason? Does it need to match the results from a real-world die?

You could completely thread a cylinder that is only as long as the threaded portion and then revolve or extrude the rest of the shank. The blend will look better but still not exactly like the real thing. That's how this one is made.

brian_brady

Any specific reason? Does it need to match the results from a real-world die?

You could completely thread a cylinder that is only as long as the threaded portion and then revolve or extrude the rest of the shank. The blend will look better but still not exactly like the real thing. That's how this one is made.

battiwallah

Thanks Brian, aesthetics only.   Alibre Design has enables a more realistic termination taper blend (pic below).

   Second question:   Is there a means (on the Onshape helical tool) to specify the length of the helix?  In the my first example above, I had to

  extrude 2 different diameters to get the transition between uncut (1 inch diam) and cut (0.999 inch diam) parts of the pin.

   Is there an easier way?

 

thanks,

vincent

(Australia)

tim_hess427

@battiwallah - Could you create your helix and then create a new curve attached to one end with a larger radius to create the effect you're looking for? You should be able to create a plane going through the end of your helix, and then create a sketch with whatever shape you want (e.g. straight tangent line, spline, or arc with larger radius). Then when you do a sweep to create your thread, you can have the sweep continue past the helix and "ramp out" of the cylinder.