On May 7 I made a post about electroplating of nickel. This can be a protective finish for reel parts, but it can also be used to increase the diameter of a male rod ferrule that is loose. I was discussing this with C. Bogart at the recent Grayrock meeting, and he pointed out that the nickel goes on in a soft condition, so the fix may be temporary. He referred me to J.E. (Jed) Dempsey, who said that a better approach is to shrink the female ferrule with a roller device, similar to a tubing cutter.
I wanted to know if this really worked, so I made such a device, shown below. It uses 3 ball bearings as rollers.
Also in the picture is a scrapped ferrule set donated by RKP. I re-sized the ferrule set for a loose fit, and then worked on it with the roller device for about 20 minutes.
The fit was indeed tightened. I suspect the the female was reduced by a few tenths of 0.001 inch.
The rollers also raised a small welt on the female, seen here on the right side of the picture (two decorative grooves were already on both sides of this ferrule set). The welt can be rolled down by further work with the device, and then sanded away. (Update 20 July 2021: I have recently been advised that rolling down this ridge may be a mistake. See the post of 20 July 2021, “Ferrule Shrinking: Avoiding a Ridge”.)
As I sit here finalizing this post, I realize that this ferrule set may be plated brass rather than nickel silver. That is why the copper color is showing through. So this still needs a trial with 18% nickel silver.
Update 19 July 2014: Yesterday I got the chance to use this device on a female ferrule of high quality, hard drawn nickel silver tubing. It worked; the ferrule fit changed from loose to perhaps a little too tight. I was surprised how little effort/time was involved, compared to the brass ferrule.