Alignment Issues

[Roy.Benmoshe]

Hi

I am creating brackets for my model rockets.Before creating the brackets I decided to model the three rockets so its easier to work off of. I am haveing a problem with aligning the the rockets. At the base (bottom) it just a circle. I would like to distance all three rockets from each other center to center 3" and in a straing line. 

[TrippyLighting]

it would likely help if you could share your design. PLease export it as a .f3d and attach to your next post.