Howzit, I have a friend that asked me if i could make two of his trolling rods shorter.. going from 6ft to 4ft.
I know i cant cut 2 ft off the tip because that would destroy the action of the blank. I am thinking i could cut the rod off at the trolling butt, move the striper guid and put on a new trolling butt thus shorting the rod and saving the action.
Ive not built any rods with trolling butts so my question is "how much of the blank fits into the trolling butt?"

Jesse,
I have built a lot of 5 foot trolling rods, called shortys. They work really well for running lines close to the boat.
Then, folks run 10 or 12 foot rods out the side to get the spread that they need.

I would simply suggest that you chop the rod at 5 feet from the tip. This could be about the point of the current trolling butt. Then, put on a new reel seat if necessary , remove one guide, and move the striper up to the position of the former 2nd guide.

By the way, when I was building these 5 foot rods, I was using a rear grip that was about 12-13 inches long to work well with the rod holders.

This is an example of the short trolling rods currently marketed by Scheels.

[www.scheels.com]

I would imaging there are many variables that can affect how you modify these rods, including their application. If these are for a heavy off-shore application, you could go with the aluminum or wooden handle assemblies, installing the ferrule piece on the end of the cut-down blank. If you are talking fresh-water trolling, for species like Walleye, I would go with Roger's recommendation. The bottom line, however, is the best "shorty" would be one that was constructed from the ground up for that specific purpose.