Gantt Chart with Custom Labels

Hello,
I am fairly new to the world of Charts and I am trying to modify a Gantt chart to show custom labels. The labels I would like to show would be Q1-18, Q2-18, etc…. The attached model reflects data from other sources condensed into this format. I have been able to create the gantt chart but having issues labeling. I have tried to put the labels on the secondary axis, but I must be doing something incorrect. Is this something anyone has experience with? Thank you in advance.