The corner slip joints for the first (base) tier are positioned 5 cm from the end of each plank and this measurement is used for the corners of all of the tiers. The slots for the tier above have been set at 20 cm in from the slots from the tier below, and again this measurement has been used throughout the construction of this planter.



Only the slip joint slots at the corners of the lower tier need to be half the plank's width in depth, this is to allow all four sides to sit firmly on the ground. All of the remaining slots used in this planter have been set at a depth of 1/3rd of the planks width.



Note that that the 1/2 depth slot is 5 cm from the end of the plank, and the 1/3 depth slot for the second tier is 20 cm in from the inside edge the first slot:



It is important to remember that on all the slip joints you are working inwards so that you keep the dimensions and the slots in the correct place.