how to dimension arc lengths?

[Mike Y]

how to dimension arc lengths in sketches, or at least find out how long an arc is? I know you can do an arc length dim in idw, but what if arc length is important to me as part of my sketch construction?
Thanks,
Mike

[JD Mather]

.... but what if arc length is important to me as part of my sketch construction?

Simply set the length up as a parameter given that circumference = pi2r(360/360)
If you can't figure it out I'll post an example tomorrow when I get back to work.
This question has been covered many times over here http://discussion.autodesk.com/forum.jspa?forumID=78
a search might turn up the example.