Buy yourself one of those long-handled brushes that you use to remove lint from a dryer and use it along with a hose to flush out your shafts. It doesn't take long for the "Varnish" to build up in a shaft so if you aren't going to take it apart every time you hunt, think about why a thinner wall shaft and a lower rod lock makes sense. There are many ways to build detector shafts and to each their own, as long as you are happy, I am happy.
Plugger
Plugger