Cs20.3 #4 Rollover Rig . .

[Don Silsbe]

Oh, I didn't catch that one.  Thanks, Graham!  Next shout's on me.

[Pete McCrary]

"Thrillsbe" asked:

Pete-- I don't see how you're going to get that block and tackle to pass through the rafter pulley, once you've got it lifted off the cradle.  I'm talking about the loop drawn in red.

ANS: The red rope PLUS the green (the "pulley part") make up the entire loop. The entire loop and the boat rotate counterclockwise together -- but only 180 degrees. The "pulley part" moves from the top-left quadrant to the bottom right quadrant -- never needing to go thru either rafter pulley. The boat and the loop don't move with respect to each other during the rotation. To lower or raise the boat the loop has to be shortened (raising) OR lengthened (lowering). If the beam of the boat is to remain horizontal (while being raised or lowered), then the loop (with its pulley part) must slid against the boat. Chick's three point method (bow eye and two stern eyes) avoids that problem.

[Designer]

Don,

 

I accept your shout but there is another rule. A shout must always be returned.

[Pete McCrary]

I liked the stern eyes and rollover setup suggested by Chick. And I found a pulley hoist rated at 440 lbs with a x6 purchase for the very reasonable price of $9.90 at Walmart's web page:

http://www.walmart.com/ip/33697781?wmlspartner=wlpa&adid=22222222227024510282&wl0=&wl1=g&wl2=t&wl3=40971765392&wl4=&wl5=pla&wl6=78914886512&veh=sem

I bought one so that I could check it out. I think it will do the job and have ordered 2 more. Then I'll have a 3-point lift for a boat with an empty weight of 650 lbs. If about half is at the stern, each hoist at the stern will lift about 163 lbs (30 lbs for my pull) and about 325 lbs for the bow eye (55 lbs for my pull). And I'll also have an easy way to lift the boat onto its trailer -- or high enough to service the CB without rolling her.

The stern lifts can be hung from exposed rafters supporting the garage's attic floor. However, at the bow, access to the rafters is blocked by an open garage door. A supporting frame could be rigged to hang the 3rd hoist over the centerline -- but more likely, I'll hang that hoist on the outside of the door frame. When I prepare for the rollover, I'll post photos of my planned setup. Maybe a member may spot a potential problem.

Top bolt about 1" below the deck.

Port-side stern eye w/ Pulley attached

Pulley Hoist rigged to lift . . .

I still have to design and fabricate a safe way to tie off each pull rope.