Materials needed: Spring ( 8mm diameter ) and glue

-Pause the print at the half and glue the spring to the smaller Part 

-Take the smaller part and put glue on the bottom of the spring

-now insert the spring with the smaller part into the half finished case and apply gentle pressure to it

-continue the print until it finishes

The smaller part should be able to be pushed down in the case. The more Coins you insert the more pressure builds up. Therefore I recomment to keep a maximum of 12 Coins in the dispenser.