Hi Bob, you mean for chamfering?

There is one tutorial that Danny did that uses a formula for chamfering here:

http://moi3d.com/forum/index.php?webtag=MOI&msg=2662.6

The video tutorial is here:
http://cid-30cffdfa97399495.skydrive.live.com/self.aspx/.Public/Accurate|_Tapers|_MoI|_V2.zip


There's also a similar thing about using a formula to determine the offset distance to use to get a particular draft angle, check out these posts for that one:
http://moi3d.com/forum/index.php?webtag=MOI&msg=941.5
http://moi3d.com/forum/index.php?webtag=MOI&msg=941.6


That second one uses Offset + Loft to make a result with a particular draft angle, and the formula gives you the offset distance required to match a particular angle.

Let me know if neither of those is what you were after.

- Michael