3-Spigot Ferrules

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A spigot is a tapered plug for the hole in a cask, thus we have a “spigot” ferrule. The blank is cut. A tapered spigot is fit into the butt section so that it protrudes an inch or so through. The tip section fits over the protruding spigot, and we have our spigot ferrule (below). I will call it a “tip over butt” ferrule because the tip (female) fits over the butt (male), which is opposite a standard metal ferrule configuration to the right.

I first cut a few inches of the butt of the blank to get a total length of eight feet, and then cut that into three equal length sections. Actually I marked the rod spline before cutting. More about that later. At each cut I recorded the inside diameter and taper. See the drawing.

The only thing that holds the rod together and aligns the sections is the press fit of the spigot into the blank. The taper being the same as the inside of the blank is the most critical parameter. That is why I choose to have Devo the machinist turn the spigots.

The first challenge was finding material to make the spigot. The diameter is small enough that solid stock is required. I found carbon fiber rod at Aerospace Composite Products, and for $23 purchases enough for half a dozen rods of this size.

Devo turned two spigots so accurately that when fitted together without glue the rod sections could be assembled and whipped around like we all do when picking up a new fly rod. Gluing the spigot into the butt section requires some thought and preparation. I used two-ton water proof epoxy. After mixing I heated it in the microwave for ten seconds. This changed the viscosity so that it was more liquid and could form a thinner layer on the inside of the blank. Glue was applied with a Qtip, and the spigot dropped into the butt section. Preparation meant that I had a dowell ready to push it through the glue. It also meant that after giving it a twist to spread glue, and pulling it tight I had a rag pre-wetted with acitone to wipe the protruding spigot clean.

The next day I slid the tip sections onto the spigots and marked how much to cut off the large ends of the tip sections to have a 1/4 inch gap when reassembled. This gap allows for wear in the future. I will always be able to assemble the sections without the two pieces of rod butting together before the fit is tight. By the way, I cut the blank with a carbide tipped blade on my power saw.

In the next post I will write about marking the rod spline and spacing guides. All the remaining components are on order.

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