My parents had an auction to sell the house and their C.R.A.P. (Cherished Relics And Possessions) last week, as they are moving into a senior living apartment complex. My siblings and I knew there was a lot of C.R.A.P. in the house, garage and shed but when we started moving stuff out to the yard for the auction we were stunned at the quantity of C.R.A.P. our parents had ratholed away. Damn auction lasted over five hours. Realizing I am somewhat of a "keeper" myself, it has prompted me get serious about downsizing and getting rid of some of my own C.R.A.P. Hence, the last two days I have been balls to the wall sorting through stuff in the shop (I'm only about 1/5 of the way through it). I hauled a bunch of scrap to the salvage yard today and gave it to the scrapper who had the most beat up truck. He was thankful for the gift. Anyway, one of the items I looked over good and decided to keep was the driveshaft from a 1940 Cadillac I used to have. It bolts right up to the '37 LaSalle trans I also kept. I noticed some bumps on the rear axle end of the shaft and, thinking it was old dried grease, tried to scrape it off. It turned out to be lead. Was it common for auto manufacturers to balance the driveshafts with lead, or was this unique to higher-end automobiles?
I don't the answer. But that were to be the case I think I would be concerned about how well it was attached.
That is standard practice where I come from and NO, the solder will not come off at any rpm an automotive engine will turn as long as it is applied by someone that knows what he is doing. Any time an electric welder is touched to a piece of tubing, the tube bends. Not so with a 500 degree soldering iron. A driveshaft balanced by the common practice of welding a washer or piece of steel to the tube can be in balance but be crooked. Not good....
All true. Anyone familiar with slinging lead knows that proper cleaning, flux and tinning will make it stick to steel quite well.
When that was built it was probably a lot simpler to have the equipment to lay lead on it than try to weld something on it too. Still from looking at a custom driveshaft I have out in the shed that I pulled out of a rig the couple of tiny spot welds holding the weight on weren't going to heat up the tube much. The guy who built and balanced that shaft used the "weld just enough so it won't fly off" method.