OK! Get into a sort of knees bent position as if you are getting out of low chair. Hold the rod BEHIND your knee joints with closed fists. One fist either (out)side of your knees. The joint is in the middle. Now widen your knees as if doing an early Josephine Baker dance routine.
The extra force of your legs should (if your grip doesn't slip) part the rod. This is what you'd see if your were standing behind an angler doing this who had his back to you. As he spreads his knees he forces the rod open. Just take care not to fall over else you've busted the rod!
Some folk (although it spoils the varnish) after assembling a modern carbon fibre rod put electrician's tape over the joint to stop you casting the topmost joint off the rod. This can happen with modern non-locking spigot joints mostly. Or worst you split the bottom of the uppermost section. Which I did with a 9 foot Hardy Sovereign once.
Old two piece split cane rods had, some, a hook on the bottom most brass ferrule of the top section section. So you pushed together then turned to lock the joint.
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