What should the specific gravity be for my dipping glaze?

Very generally speaking, ideal specific gravity for most dipping glazes is between 1.4 and 1.6. However there are a lot of variables which influence the ideal SG for your application. Sue McLeod explains it very well at this link: https://suemcleodceramics.com/why-specific-gravity-isnt-listed-on-glaze-recipes/