Thank you for your replies. After working with the software some more I think you are right that copying and pasting the frames is the easiest way. I'm actually trying to make an animation of a clock gear train that I'd like to have run through an 1 hour motion, obviosuly at an expedited pace. So the escapement gear alone has to repeat 360 degree rotations 60 times in 6 degree increments to be realistic. Thats 60*60 = 3600 frames minimum! I wasn't sure that animation lab could handle that many frames so I thought that Do Loops in the script might be the easier way.