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Chris Lewis

According to :
160 is generally not a lotof weight, but then add to it the weight of
the chain and block and tackle, etc and you're over 200 maybe going
toward 250. The only concern I would have is that being a truss roof
it is engineered to support a load from the top, not necessarily from
the bottom. A truss is one of those things where whole is stronger
than the the sum of the parts. I would suggest trying to put the
support beam above the ceiling joists and to have the support beam span
as many beams as you can (at least 2-3 on each side). This will spread
the load more evenly among the beams. I also suggest you use a doube
2x4 or double 2x6 with boards on edge as your support as the wood is
much stronger on edge than flat. Its probably over-engineering, but
even a little flex will crack your sheetrock on the ceiling.

Keep in mind that roof trusses pretty well have to be engineered
well enough to support a person walking along the lower chord.
Which conservatively would be on the order of 300lbs on _each_
chord.

That in mind, I did the following: a chunk of 4x4 extending over
4 truss chords (on top). It just so happens that the 4x4 is
immediately adjacent to truss ties to the upper chord.

The hardware is all rated for at least 1000 pounds working load.

Massive eyebolt thru the 4x4, and a heavy thread style quicklink
between the eyebolt and a chain hoist. The chain hoist is thus
hanging below the truss chords.

I imagine that I could safely lift 1000 pounds (the hoist is a
1 ton unit) but I'm a chicken, and am going to limit it to a few
hundred pounds at most. So far, the heaviest it's had to lift is
the front end of a lawntractor (200 lbs or so). No noises/creaking/sag
whatsoever when I did that.

I'm not into R&R'ing automotive engines and other heavy things.

I'd reinforce it (possibly with the assistance of an engineer)
if I thought I'd have to do full drums or something like that.
--
Chris Lewis, Una confibula non set est
It's not just anyone who gets a Starship Cruiser class named after them.