Bamboo rod makers: have you abraded a male ferrule just a bit too much? A quick fix may be to slightly shrink the mating female.
I have been making a ferrule shrink tool for several years now, and I think that I have a good design. Click on the “Ferrule Shrinking” tab just below the headline photo on this blog for more details.
Anyone with a home shop lathe and mill can easily make one, although I continue to make and sell them. In this post, I am providing construction details so that the design is not lost.

1. First make blanks for the front and rear aluminum plates. These are 2-5/8 diameter, 3/8 thick, and have a 5/8 diameter through hole at the center.
2. Clamp the two plates together on the mill table so that all holes can be “match drilled”.
3. Machine the plate details according to the drawing below. I have been drilling the two holes of 5/16 diameter and the three holes for assembly screws. The only actual milling tasks are plunging the 21/64 counterbores and cutting the slot.
4. Make 3 spacers, 3/8 diameter, 0.355 long, and with a #10 drill (0.194) through hole.
5. Press 5/16 dowel pins (1 inch length) into three ball bearings, 1603-2RS. Do not allow press forces on the balls; make a sleeve of 5/16 I.D. and 0.33 length to support the inner race during the press.
6. Assemble plates, spacers, and bearings with three screws, #10-32 x 7/8 socket head.
   I have been placing washer shims (9/16 OD, 5/16 ID, .003 inch thick) on both sides of the two fixed bearings. These shims prevent bearing outer races from dragging on the end plates. They are not strictly needed; most assemblies will operate well without them.
7. Grind the tips of the two radial screws (#10-32 x 1) flat; these bear on a dowel pin.