You could probably put it in for an hour and then the tin foil will hold the heat.
With tin foil theres one dull side and one shiny side. In the photo it looks like the shiny is on the outside.
Generally when you have it in the roll back, the top is shiny and the bottom is the dull.
Really you need two with the shiny on the inside and two with the dull on the inside and it'll balance its self.
Lol I'm a catering student so and we use tin foil for all sorts of things and Know a lot about it and ways to use it😂 Sad I know.
But yea you can tell which side is which with a light too, the shiny side will reflect the light and shine a lot the other side thats dull wont reflect the light very much, so its not shiny.
Last edited by Ria; 04-21-2019 at 08:57 AM.