Is there a way to show NPT threads with a cosmetic thread

In 2005 & 2006 when you add cosmetic threads to a tapered hole or tapered outside of a pipe, the cosmetic thread follows the angle of the taper.

This is true for 2004 also. However the number that you specify as the minor diameter is not actually the minor diameter. It is an offset of the taper surface. That is the way it is in SW2005 also.

On a similar note, there is a bug with cosmetic threads on tapered surfaces in SW2005. The problem is that you can not double click on the cosmetic thread feature in the feature manager and get the dimensions to show up in the graphics area. Therefore you can't select it to add it to an equation. You can't even manually type the dimension name into the equation, given that you were able to guess the correct dimension name (there is no way to get to the dimension properties to see). It's as if the dimension does not exist at all after you create the cosmetic thread.

The SORT-OF work around steps are:

1)delete existing cosmetic thread 2)remove angle from extrusion (or revolve feature) so it's a straight as opposed to tapered 3)re-create the cosmetic thread 4)create equation...it should take again "D2@Cosmetic Thread1 = blah blah blah 5)go back and re-taper the feature

This keeps the dimension that is now usable for equations and such. But the thread will not display properly now.

According to my VAR, this is supposed to be fixed in SP4.0.

I still cant figure this out. Sorry. Anyone have a model/drawing as an example?

Select the small end outside diameter edge of the pipe. Click Insert>Annotation>Cosmetic Thread. Specify the length in the first space, and the "offset" distance in the second space. Typicaly this it the diameter in the second space for straight cosmetic threads. But for tapered cosmetic threads, it is the offset. The cosmetic thread will then be there.

You may not be able to actually see the threads until you:

1. right click on the annotations folder and select details
2. check cosmetic threads or shaded cosmetic threads (your preference). I like shaded best.
3. check display annotations You may have to uncheck some of the other items that you don't want visible.

They should show up automatically in drawings.

Seth

Thanks for helping, but I have more questions :)

So is the offset value the "Pitch Diameter at the Beginning of External Thread" as called out in the Machinist Handbook? Also, the chart im looking at doesnt have the thread length, only the "Effective Thread" length. What chart do you use for pipe dimensions?

Oh, one other question to add to the questions above, do you have to chamfer the end of the pipe to get a taper thread?