Assemble center post from 3 inches up to 6 inches in 1/8-inch increments to match the height of your cake tier.
See video below for example.
Measure your cake height first. Use this measurement to assemble your center post.
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Subtract 2 inches from your measurement to choose your threaded rod. If your cake is 6 inches tall then choose the 4 inch threaded rod. If your cake tier is 4 ½ inches tall then choose the 2 inch threaded rod. Always take 2 inches less to choose your threaded rod length and set aside.
Lay out your 2 threaded end pieces on a ruler equal the height of your cake tier. Choose the spacers needed to fit between them to exactly get the height for your center post then put your center post together.
Thread one end piece to your rod set aside, then slide the spacers, then tighten with your other threaded end piece.