Glaze the inside first! Wipe away any drips, allow to dry, then spray the outside. If you want the inside glaze to overlap the outside glaze at the rim, clean an appropriate portion of the rim bare after you glaze the inside, then do a rim dip after you spray the outside. If you don't want any of the sprayed glaze to get inside, you might be able to use Press and Seal wrap or wax resist to mask off the interior during your spraying.
- Joseph F likes this