Pre-heat your stove to 135 degrees. While your oven is heating up, you can do everything else you need to; this will save you a heap of time.
Remove the core from the pineapple.
Cut the pineapple into ¼-inch thick slices. You can make them thicker if you so choose. Keep in mind that it would take them longer to dehydrate.
Place the pineapple slices into your stove and let them sit until they are dehydrated. This will usually take a little more than six hours to complete.