Tapered Thread - Thread Profile Normal to Tapered Face

[Malcolm Crowe]

These tips are based on lessons learned while trying to create a "Tapered Thread" using the "Thread Tool", where the thread profile is "Normal to Tapered Face". Hopefully these tips will save a lot of time and frustration for other users who need to model similar tapered threads.

1. Select the part (tapered body) and set the modelling kernel to PARASOLID. Using ACIS is very problematic, so save yourself a lot of trouble and only use PARASOLID when modelling these tapered threads.

2. Create both "Positive and Negative Inclined (Tapered) Versions" of the "2D Thread Profile", where the angle of incline (taper) within these 2D profiles matches the taper of the face to be threaded. This is demonstrated in the attached video. It is important to add an unlocked vertical dimension for the "Vertical Pitch Distance", as this value is needed in the properties of the "Thread Feature".

3. Select the part and then select the "Thread Tool" from the "Features" group of the Ribbon Menu.

4. Within the "Properties" of the Thread Feature, set the "Start Pitch" value as the same as the "Vertical Pitch Distance" of the Tapered Thread Profile. This is very important!

5. Set the direction of the thread. Whether from top (downwards) or from bottom (upwards).

6. Select either the "Negative or Positive Tapered Versions" of the 2D Thread Profile. The direction of the thread (above) determines which profile needs to be used. This is important, and the reason for having both versions available of the Tapered 2D Profile.

7. Set other thread feature properties, such as the Start Distance (offset) and Thread Length to suit your needs. Note that the Thread Length will automatically recalculate whenever the "Surface" is re-selected.

8. Note that the "Ending (0-1 revolutions)" within Thread Options doesn't work with Tapered Threads. Only Parallel Threads.

If others have additional or alternative suggestions then please share.

Malcolm

TAPERED THREADS - 20210304.ics

Edited March 11, 2023 by Malcolm Crowe

[Cary OConnor]

Thanks for the post. Very good write-up!