I will start by saying I throughly detest Porter bee escapes. I have two good reasons for this. The first is the escape it’s self is prone to failure. It might be a fat drone getting stuck or it might be the springs are not set properly and the escape fails. Yes if it’s in the garden it’s no big issue but if you have driven a distance it is a real pain to find the supers full of bees still.
My 2nd reason is that the supply companies love to sell crown boards with the holes pre cut for the Porters. This in turn leads on to fiddle fadding winter feeding. People make up little amounts of candy and put it over the porter hole and think they have fed the bees with 250 grams of feed. Err… no. I put on feeding ekes and give four or five kilos of bakers fondant at a time. I then leave them to it and check once a month to ensure they have feed, and I like to see feed still there in Spring.
My escapes have no working parts and can be made at home by anyone who can use a hand saw and a hammer. Please see the pics below. Being a tight git I cut plastic escapes up to fit my boards as I think the escapes in the corners work better than with the hole in the middle.