I'm just hitting the age that my Dad was when he passed--taken by renal carcinoma in his early 70s, a disease closely connected to working with hazardous materials (which he had done for a lot of his life). It's shocking to think that he must have felt pretty much like I do now-- except for the disease--which is to say, not feeling old, and still feeling like there were projects to finish and things to do.
He was a farm kid turned aircraft mechanic, car mechanic and then machinist/tool and die maker, and had more skills across a wider assortment of trades than anyone I have met since. He also could just get stuff done--there's a picture of him as a young man on the family farm, on leave from the Air Force (WW II), and my brother's quip was "If you asked him to go plow the back 40, he'd get it done."
My brothers and I worked along side him from our early teens on and even though there was too little time for training, all of us picked up the basic skills of troubleshooting and especially the knack of procedure driven approaches to solving problems. I wish there had been time for more instruction--I'd love to have a tenth of his facility with a welder, never mind some of his extraordinary abilities as a machinist.
What gets more remarkable though as I age is that he would start every day with optimism--and the phrase that sticks with me was his standard comment after a brutal day where the bear got us--'Things will look better in the morning!"
More often than not, it did.