I-DEAS models (.mf1) can most likely be converted to plenty of other 3D modeling formats, including STL format for 3D printing. You can use one of the several available converters for this mf1 to stl conversion, some good picks are listed below.
Convert I-DEAS model file to Stereolithography CAD file.
We have found 2 software records in our database eligible for .mf1 to .stl file format conversion.
On-line services software - convert mf1 to stl on web
A commercial online CAD converter
Convert from mf1 file format
The tables with software actions are a good pointer for what a certain program does with various file types and often may give users a good hint how to perform certain file conversion, for example the above-mentioned mf1 to stl. However, it is not perfect and sometimes can show results which are not really usable because of how certain programs work with files and the possible conversion is thus actually not possible at all.
An online CAD conversion service