Slice the top and sides off of the pineapple with a sharp knife. Leave the bottom intact. You will need a non-slippery surface to hang on to as you slice the pineapple.
Using a mandoline slicer, slice the pineapple as thin as possible. If you don't have one, you can use a sharp knife instead. Just be sure to cut the slices as thinly and evenly as possible.
Place the slices on a dehydrator, leaving some space between the slices for air circulation. Once the racks are full, cover with the dehydrator lid and choose the vegetable/fruit setting. On my dehydrator, it's set to 135 degrees F.
Begin checking the pineapple chips after 3 hours. Mine were ready after 4 hours. The chips are supposed to be crispy, but if you prefer them more pliable, remove them sooner.
The chips will get crisper as they cool, so don't expect them to be crisp before removing them, or you'll overcook them. They're almost too beautiful to eat... get over it, and eat them!