At what point (i.e. chuck weight) does one need a hoist or chain fall to install a heavy chuck?
I just bought a chuck that weighs 107 lbs. I would not expect to be able to get that on & off without a hoist such as this:
At the time (1982ish) I was working "Civil Service" as an electrician at a Naval Station, there was a limit of 35 pounds on what could be lifted. (??Navy or OSHA??) My electrician's pouch was nearer 40 pounds so the "rule" was usually ignored. In my own shop, there are days that I am willing to try 200 pounds and there are days that 10 pounds is too heavy.
I have acquired a "wheelchair lift" (cheap) that is almost identical to an engine hoist, just half the size and shiney. On the days I feel weak, the hoist can be dug out. If I'm just lazy that day, the time to dig out the hoist isn't worth the trouble, I just pick it up (using proper lifting techniques) and go.
Sometimes, if I think I'll need to shift my grip, I'll hang a tie down strap from the ceiling joist as back-up. Such as mounting the Atlas Milling Machine on a stand. . . I use a 12X36 inch Atlas lathe. The heaviest chuck I have is a 10 inch 4 jaw. I have no idea what it weighs, just that some days I don't feel like wrestling with it.
Working around a precision machine such as a lathe, I would want at least a back-up for any heavy (over~10#) part that could drop and damage the ways. That's why there is a piece of plywood kept handy. The plywood is always in place on the bed of the machine, even if I'm mounting the 3 inch chuck. The MT-3 adapter for it is heavier than the chuck. . .
I'm 70 now, I'm haven't been 31 for a long time. For anything heavier than I am capable of handling, I would use the hoist. I say
handling vs lifting intentionally. Lifting is just part of the process. Handling, or
controlling, what is lifted is much more important. I don't think the hoist pictured would be the most useful. But every person is individual and every person's capacity changes day to day. I use a wheelchair lift because it has shorter "legs" than an engine hoist. But then. I have floor space to handle it. If nothing more than a motorcycle tie down over the joists, anything is useful. Even my "mill shoes" wouldn't be much help if I dropped the 4 jaw.
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