It is now time to trim our sections to length.  It would be simple for our 7’ 6” rod, or 90 inches, if we could trim the butt and the two tip sections at 45 inches, glue on the ferrules and call it a day.  Not so simple!  If we assemble this rod we will end up with a rod that is not 90 inches, and the butt and two tip sections would not be of equal length when put side by side. Here’s why.  
 

The tip top adds length to our rod and must be accounted for.  It adds a good 1/4 of an inch, give or take. 

 

The male ferrule slides into the female ferrule by 0.600 inch, this shortens the overall length of the rod and must also be accounted for.

 

Finally. When fitted on the butt section the female ferrule adds, you guessed it, 0.600 inch to the length of the sectio.  Again, part of the math that we need to do.