rear lift eye loading
Printed From: CorrectCraftFan.com
Category: General Correct Craft Discussion
Forum Name: General Discussion
Forum Discription: Anything Correct Craft
URL: http://www.CorrectCraftFan.com/forum/forum_posts.asp?TID=832
Printed Date: December-02-2024 at 6:20pm
Topic: rear lift eye loading
Posted By: boat doctor
Subject: rear lift eye loading
Date Posted: September-20-2004 at 4:08am
have refurbished 1964 cc american skier, too old to ski but fell in love with the lines of this old classic. retrofitted pmc 302 for the old 260 new weber carb 600 cfm edelbrock int. mallory unilite dist.now have a set of GT 40 heads to finish up my need for speed. my quest for more ponies has to do with pulling a 26 ft. parasail, having already pulled with 150,250,310 ft. i am not noticing any movement on rear lift eye. but a post on loading has made me wonder. the rtope used is 1/2 polypropolene,not the strongest stuff by any means. being this old boat does not have a transom aka outboard/steardrive there is no strong area to attach ski eyes to the rear below the rub rail. any ideas, or will the lift eye preform this misson. btw an oj 13x13 four blade pull the chute like a john deere and still tops out at46.9@4400rpms love that 64 boat doctor
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boatdr
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Replies:
Posted By: David F
Date Posted: September-20-2004 at 3:19pm
The lift rings on ALL correct crafts are designed to carry verticle loads equaling about half the weight of the boat. With that said, I have used the rear ring for years to pull tubers without any problems or signs of stress.
In order to better evaluate the lift rings suitability for purposes other than lifting the boat, you should know the following:
1. The lift ring is attached to a threaded rod which in turn is attached to a steel angle (or similiar depending on rear). This angle is anchored (glassed in) to the transom. The method of attachment to the transoms depends on year of the boat.
2. The two exposed screws on the flange of the lift ring is only designed to keep the lift ring from rotating or moving slightly laterally on the deck.
3. The deck around the lift ring is support by plywood blocks via a nut on the threaded rods. This prevents the deck from flexing downward and producing an unsightly gap (and striping screws) at the base of the lift ring.
So, as you can tell by the above, the ONLY thing that allows the lift ring to handle lateral loads is the thickness of the fiberglass deck resisting the sideways load on the base of the lifting ring (the portion of the lifting ring that penetrates the deck. Therefore, it is possible that a significant lateral load can tear or crush the fiberglass deck resulting in failure.
With all the above said, the least you should do if you insist on using the lift ring is to reinforce the fiberglass deck from below by laminating additional fiberglass fabric to the bottom side of the deck around the lifting ring. Even consider glassing in an aluminum plate to distribute the lateral load across a much wider area. Take this for what it is worth.
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