My company insists on modeling helical threads. I am not sure how to attach the profile to the helix when modeling these. Could someone help me out with this please? Thanks
This has been covered here (and other sites) numerous times. A search might turn up some examples. (Check Mike Wilsons site - I think he has a goode example.)
You can change the start angle of the helix. Attach what you have completed so far if you can't figure it out.
The first step is to make sure that the starting point of your helix is on the same plane as your sketch of the thread profile.
This can be achieved by changing the starting angle of the helix (as rollupswx suggested) so it starts on an existing plane. Or create a new plane perpendicular to the start point of the helix.
Then, in your sketch, make part of your thread profile coincident to the helix starting point, or pierce the helix (or somehow dimension it from the helix starting point so the sketch is fully defined).
It is normally a waste of time and computer resources to model threads, unless you plan on using the model to extract CNC data. Most companies I have worked with do not.
Check the FAQ section: faq559-1492. Also, I presented on this topic at SWW this year. The video and presentation should be available on the site in a few weeks.