Re: CAM--Iges STL

From: C. Brock Rooney (
Date: Wed Jul 08 1998 - 02:24:13 EEST

At 01:40 PM 7/7/98 -0500, michael rees wrote
>Dear List,
>How many CAM programs are going to the .stl file as an option for
>What are the major drawbacks of using STL instead of Iges?
>I would assume that an iges file, with the nurbs information, would make
>a smoother finish on the part. The part made from STL would be as
>faceted as the original stl file, unless further operations were applied
>to the file.
>Does using an STL file solve more problems than it creates?

Many CAM programs use a faceted representation of the surfaces internally.
So there is no special downside to using STL files.

For NC cutter path generation, you would usually want to use a tighter
tolerance when generating the STL files. When you generate a cutter path,
you specify
tolerances. So you probably want the STL faceting error to be some fraction
of the cutter path tolerance.

Out IGES to STL product has been used sucessfully to create STL files
for NC machining puproses. Indeed, two CAM system vendors offer special
versions of BR&A IGtoSTL as add-ons to their CAM products as a general way
to get IGES surface info into their systems.

C. Brock Rooney, Pres., Brock Rooney & Associates Inc. (Brockware)
        915 Westwood Birmingham MIchigan 48009 USA
(248) 645-0236 fax/bbs (248) 645-9020 email

For more information about the rp-ml, see

This archive was generated by hypermail 2.1.2 : Tue Jun 05 2001 - 22:46:10 EEST