Have a 903 fly rod where the two sections where not seated correctly. Tip section came loose & broke off 1/4 inch of
the male ferrule on the butt section. Still have 1 1/2 inch overlap. Will glueing an insert inside the male ferrule section
strength it ok. There was some splittering. If I cut the end down, the tip section will not fit. Will change the ID/OD

All you can do at this point is shore up the male section so that no further splitting occurs. Glue a thin wall insert in place and bind it tightly with a rubber band to ensure the fit remains the same. Let cure remove the rubber band and clean things up. If you have the RodMaker issue before last, you have the information for properly sanding the ferrule for a perfect fit. A light bit of work here might restore some of the original overlap and allow you continue using the rod trouble free. Worth a shot. I think with some careful work you can salvage the rod.

Or, send the blank butt in for a replacement.

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