Normally I do about 20 of this in an afternoon an most of them are the same size. The trick is to place two sets of "E" laminates at each side with the their fork sides facing each other. It is like shuffling cards but a bit slower. Once you are done with the "E" laminates you just have to insert the "I" laminates. Unfortunaly I did not have a wooden mallet that day and some of the cores were damaged and recycle. The hardest part are the las 4 "E" laminates more than once I can't fit all the laminates back.