Well, tried popping it apart and several plastic parts just disintegrated. Battery case, brush holders. And internal corrosion was pretty extensive. tried saving the chuck but it's not removeable. I figured if all else failed I'd get a 1/4" chuck. Oh well, you win some, you lose some.

That museum is pretty interesting.  Never went beyond basic geometry myself, due to a couple of teachers that did their best to sour me on math.  In high school there were the upper end kids that were given trig and calculus, wore their long slide rule holsters as a badge.  Have picked up 2 slide rules at thrift stores as curiosities.  Just found a 6 inch that is marked USAF, made for using on a glass table analyzing aerial photos. 

A few weeks back while working in Wichita I stopped at the Yardstore and bought 2 12" 4r grooved rules and a 24" 4r grooved rule too. I head that way again on Thursday and belive I am going to swing by there again and add an 18" 4r rule to buy the last grooved rule I intend to buy.

I way have mentioned it in an earlier post, but until supply evaporates, the Yardstore sells the same grooved rules as HJE if you are looking for the traditional 4r measures in 12", 18", and a rapidly dwindling number of 24" grooved rules for considerably less than HJE. However,  unlike HJE, the Yardstore does not sell 4" & 6" grooved rules.

Regardless where you choose to buy grooved rules just know that I believe it quite likely buying new or seconds USA made grooved rules will not be an option within the next few years.

It's always nice working with cleaned and freshly painted parts.

I'd be doing it.

Mind you, after my current build apparently there's not a lot I won't do!