DSF

but you're not using the vacuum

Although loud it does help to have the vacuum turned on.

The reason I say is because if you are doing a full bleed mug with colour running off the top and bottom you will inevitably have paper and subsequently ink overlapping the mug. As you know the ink turns into a gas. To prevent this ink from "landing" somewhere it shouldn't (i.e. inside the mug) I turn the vacuum on to suck it out of the oven.

I hope I have explained that properly

really interesting, thanks. think an adkins or similar quality press maybe the way to go then. not fussed about phone cases or anything like that.