solder mask and tracks clearance

[Omar Khater]

Hello guys 

I wonder how to change the clearance between solder mask and tracks (this tiny distance shown in the picture below)

and how to measure the distance in orcad 16.6 

[Ron_O]

You can set the soldermask size for pads in the Padstack spreadsheet.  Set the mode to Pin (click on Pin icon), select the pad, press shift-T to call up Padstack spreadsheet, then adjust the value of the SMT, SMB layers accordingly.  Typical soldermask oversize is 5-6mil. The other option is to use an oblong pad shape to reduce land area on the track side and extend on non-track side to maintain good solder fillet.
RonO