Off the shelf cool boxes can be good but the better performing ones can carry a hefty price tag too. A bit of research indicates that performance is directly related to the thickness of the insulation. I also wanted a box that would fit in a kitchen cupboard, the best option then was to make one.
It is built from 100mm foil backed foam, (found in a skip) glued together with silicon.
I then wrapped the whole thing in parcel tape.
And then in foil tape. I am not sure this adds to the insulating properties, but it was a quick easy way of getting a nice finish. The sides of the box had to be trimmed down to 75mm in order for it to fit in the cupboard.
The lid is a piece of mdf hinged with a bit of recycled piano hinge, with a foam 'plug' that fits snugly in the top of the box.
The whole thing is mounted on a couple of old drawer runners so it is easy to move in and out of the cupboard.
It will be interesting to see how it performs. It only cost me the price of the foil tape (£5.99) so I cant be too disappointed if it is not very effective.