Concealed Kitchen Cupboard Hinge (Blind Corner)

I designed this to replace the metal hinges on my camper van conversion, for the cupboard where the gas bottle is held. The problem being that the gas bottle will only just fit through the door opening and the door gets in the way even when open, preventing the gas bottle being swapped without unscrewing the hinge from the inside of the cupboard.

So, I designed a hinge that would mount in the same place and work in the same way normally but had a quick release lever that would allow the door