Joe rented welding equipment and Pops worked for him. This was back in 1940s through the 1980s, before prefabrication, when a lot of fabrication had to be done right on construction sites. So Grandpa had for rent arc welders, torches, and things which I think were called buzz boxes. As that's good enough for the point of this tale, we'll leave it at that.
These buzz boxes were intended to make instant welds. As I recall, you would hold the thing up to a rivet on a steel girder and it was supposed to make three quick welds to secure the rivet in place. Supposed is the operative word here. The boxes were notoriously finicky, and it was Dad's job to go out to work sites to repair the them when they didn't work.
Pops hated them. They were as difficult to repair as they were to operate. Over a few years Dad learned to fully and completely despise them.
One day as he came in from a particularly tough repair on one of the buzz boxes, Joe could see that his son was not in a good mood. Pops could tell his father thought that maybe he could lighten things. He remarked with a slight chuckle, apparently trying to make a joke of it, "Those buzz boxes are tough to deal with, eh?"
As Dad told it, he replied quietly, firmly, and without looking up at his pops, "Old man, when you die, I'm selling those buzz boxes. Then I'll bury you." It's an old line, but used rightly, an effective one. Perhaps Dad had been holding it back, waiting for the teachable moment.
Joe laughed at it, but kind of nervously. The next day he began selling the buzz boxes.
Pops could let Joe know what he felt when he had to, and without the arguments Joe often had with others. And I think they respected each other because of it.