You need to mark just the ONE side of your two arms.

Because you are making this proportional divider yourself, I have included the instruction to label your ends 1 and 2

If you purchase a PD you may not see this feature on it, however, the 1 and 2 should be an indication to you of your process, as described to you in our previous lecture.

You will begin with measuring on one and drawing on 2.

In order to allow the PD to pivot as it should, but also to maintain that center pivot, I used a small piece of prestik to place between the arms on the matching dots, and then secured it with a drawing pin.

It really does work, but you do need to be gentle when handling this foam board tool. The prestik will secure the angle while the drawing pin holds the pivot.