I have a Prindle 16 cat and need to build a crane to lift it 4 feet vertically onto some dock brackets. I can't beach it and spend too much rigging.

Anyone tried to lift a cat without damaging hulls. I'm not sure if I will need to build a sling or can grab the aluminum frame. Once on the brackets the crane will no longer be carrying any weight. Thought I would try to get it done with one small 600LB max crane.

Scott

Check out davitmaster dot com/7_elevatorLifts/marineElevator.asp
This was the system that my boat was on when I bought it.
May be too pricey, but you can see the design.
The previous owner of my boat wouldn't sell me the lift.
I don't know why.

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Todd Elozory
H18
H21SE
Hobie Mirage Tandem Island
Catalina 22
Thonotosassa, Florida
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Thanks Todd but this is very pricey and worth much more than my cat.

I have a couple of large L brackets I can sit the cat on but just need to lift it straight up. I was hoping to be able to grab the aluminum frame running between the hulls at each end (4 places). I could just wrap around the hull and hook onto the aluminum frame from below. This would add some torque to the hull but nothing compared to sailing her. I figure I could buy or fabricate a simple crane for a few hundred bucks.

Anyone seen something like this?
Scott

I too have a 2-3' breakwall & considered this idea. The real problem you face is leverage, not weight. Unless you can fold the "L" brackets, lift the Cat, then replace the brackets, you are looking at having the crane reach out at least 12' (8' to clear the brackets, plus 4' to hoist from the middle of the cat). Otherwise you have to have a traveling crane,(lift the cat, then travel over the brackets)
Another option I considered was to build steel "L" brackets, with a cross bar welded at the top & bottom of the "L" to lock them as one piece. I was going to have the brackets slide vertically in pieces of channel iron. The brackets could be dropped onto the lake bed, Cat floated over them, then winch the assembly upwards. The advantage is the winch could be mounted right at the edge of the breakwall, & the line attached to the end of the "L", creating very little leverage. In the end it was easier to buy a seadoo lift, & place two 8' crossbars on it. I float the Cat onto the lift & crank a few easy turns.
I still have the crane, was going to use it to hoist docks & boatlifts out at season end, but the breakwall is not strong enough to hold the leverage once I swing it out 5-6' Those small 600lb cranes might only be good for lifting into a truck bed, a 1-2' lever. The further you lever out the stronger eveything has to be. I even considered a cantilever beam & placing a plastic drum on the other end, then fill it with water to counter balance the lever arm out over the lake.



Edited by Edchris177 on May 23, 2011 - 09:03 AM.

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Hobie 18 Magnum
Dart 15
Mystere 6.0XL Sold Was a handful solo
Nacra 5.7
Nacra 5.0
Bombardier Invitation (Now officially DEAD)
Various other Dock cluttering WaterCrap
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This will be mounted to a large dock system, lifting the boat straight up. Once in position the two 8' long L brackets will be swung 90 deg in to a perpendicular position from the dock and hulls as they pivot on round pipe. The crane will need to support the 350 lbs at 4'6". The additional clearance (6") is so I can keep it away from the dock (bumpers) until up in position. Then I will manually pull it in 3" towards the dock and drop it onto some carpeted V supports. Crane and L brackets each have a brace reaching down at a 22.5deg to support some of the loading.

What I do not know is if I can pick up the boat by the aluminum cross members? Four points (each end) supporting about maybe 100 Lbs in the front (200 total in front) and another 70 Lbs at each end of the rear for a total wet rate (no riders) of 340 Lbs.

Scott

Of course you can pick the boat up by the beams. See the "Tilley Tilting Trailer" (misspelled 'tilly') here:

http://www.thebeachcats.c…ictures/?g2_itemId=11313

How do you move a boat around on the beach? Often by picking it up by the cross bars and moving it around. Might not want to hang it from the cross bar without further investigation, but if you are just picking it up and then setting in on supports I see no problem picking it up by the frame. I would focus on the balance and rope lengths needed to pick it up flat.

I hope you are not lifting it with people still on the boat.

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Scott,
‘92 H18 w/SX wings
‘95 Hobie Funseeker 12 (Holder 12)
‘96/‘01/‘14 Hobie Waves
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