Most of my Snap On screwdrivers range from the late 70's to the mid 90's or so with a few replacements made over the years.
So far I haven't had any of my plastic handle screwdrivers deteriorate but about a year ago, I had put a new set of the early rubber grip handle screwdrivers which I picked up new in the box at a swap meet off a dealer about 20 years or so ago. They package was still sealed up. The guy said he was retiring and selling everything at a big discount. I bought about $400 worth of stuff that day but face value was about four times that in the catalog. I bought four dead blow mallets in orange, the 8 pc set of gray/black rubber grip screwdrivers, two 4 piece sets of orange handle picks, and a metal cased set of micro screwdrivers with purple handles, (off hand I'm going to say its a 24 pc set). I tossed the some of the items in my spare box down in the basement, and put the micro screw drivers and pick set on the bench. The mallets went in my main tool box in the garage.
The other day I opened up the hammer drawer and more than half of the orange hammers and mallets had all but turned to dust. The orange plastic had cracked and fallen off, and what hadn't fallen off, crumbled in my hand. 9 pieces in all. They were fine two weeks ago. Then I found one odd rubber handle cotter pin puller that had gotten sticky, and the plastic under the rubber was all split and crumbling. After seeing that I checked a few other sets and found that new set had fogged up the plastic and the handles looked shiny or oily as if the rubber was melting. The plastic on the package was still sealed.
None of my other plastic handles show any issues, but have had a few really old odds and ends that I've found over the years turn waxy or white but I've cleaned that off and it's never returned.
I still have a few sets of the old 80's style Snap On screwdrivers that are still new in the box as well in both red and black. (Those sets came with black flat drivers, and red Phillips drivers). I stumbled onto them at an estate sale about 10 years ago, I think I bought 9 sets that day with the thought of listing them on fleabay but they never sold, I couldn't even get half of the original list price for them so I threw most of them in my own tool box to use.
Old Craftsman screwdrivers though are notorious for turning hazy or waxy with age.
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