Printrbot Simple Metal Spool Spacer

This is my first 3d design, which I made for my Printrbot Simple Metal. I am using Harchbox filiment and these filiment rolls do not have a notch inside the arbor for them to ride on the spool holder, so the roll would ride against the z axis rods. If I wanted to print something tall, the z axis motor would hit the filiment spool and my print would fail. I used a toilet paper tube and cardboard for a temporary fix until I got this printed. Now I am able to print the entire length of the z ax