3 point lifting harness for sr 5.4 (dimensions needed)

boatster_sr4 · 29 March 2007, 20:21

Does anyone know what the dimensions/measurments of a 3 point lifting harness would be for a standard ex-mil Avon Searider 5.4. I have two U-bolts facing inside on the transom and one u-bolt at the bow facing inside as well. My 5.4 is a completely stock layout from Avon.

I need a three strap harness that goes to single point hooked crane for loading off of a pier.

Cheers.

Tim M · 29 March 2007, 20:31

I think you'll find that the searider 5.4 harness has 4 points. The one I had certainly did. The eye in the center at the front isn't designed for lifting - its just for tying things off. The lifting points fitted at the front on mine were pretty chunky.

boatster_sr4 · 29 March 2007, 20:49

Hi Tim,

My boat doesn't have 2 points at the front. I have 1 thru hull U bolt that seems to be pretty well anchored. I'm pretty sure my 5.4 is setup to be hoisted but now I wonder if it was by a cradle. It served as a "to shore" boat on a large US Coastguard cutter. I've seen 3 point slings before though so I can't see why it wouldn't work in this case.

Could you tell me where the forward 2 lifting points are on your 5.4?

dctucker · 30 March 2007, 01:51

I lift mine all the time with the 3 points. That IS what they're there for. I'm usually launching at a sailing venue with a hoist, and I'd rather keep the trailer out of the salt water whenever possible. I emailed Avon and they gave me the lengths. Zodiac USA wanted an insane amount of $$ for a harness, once they got around to replying. Do a search of the board, I posted the info on lengths here somewhere...

I simply put long eye splices into 1/2" (5/8"? 3/4"? can't remember) nylon three strand dock line, and "luggage tag" attach to the lifting eyes (put the loop through the lifting eye, then the other end through the loop). I'll probably redo them at some point this season with 12 strand Vectran or Dyneema (now that I know how to put an eye splice in it

), maybe with a big ring in the center of the three, with heavy duty stainless Wichard snaps to attach to the boat if I want to spend $$ and get fancy. The nylon dock line was cheap and easy, but the aft ones do stretch quite a bit as the boat lifts. I'd shorten the afts a few inches, or lengthen the forward 4"-6" if using the nylon line. I doesn't concern me from a safety standpoint, but it throws the balance off a bit. The SWL of the line is sufficient that one line could handle multiple 5.4's.

I like New England Ropes V-12 Vectran. 6mm=7500lb tensile strength, 8mm=11,500 lb, 10mm=16,880 lb.

Alternately I'd go for New England Ropes Endura 12 Dyneema: 5mm=5800 lb tensile strength, 6mm=8500lb, 8mm=13,300lb.

Choose your safety margin vs. cost...

dctucker · 30 March 2007, 02:02

Boatster, here's the link to the other thread, 3 pages.... Started 1 year ago, almost to the day!

The key details, per Avon:

Forward leg - 109.5 inches.
Stern legs - 84.25 inches.
The sling should be constructed to have a Safe Working Load of 1.5 ton. and a Proof load of 3.0 ton

So the 6mm V-12 would do nicely, but the 6 mm Endura is less $$.

boatster_sr4 · 30 March 2007, 06:43

Great!!! Thanks dctucker!!

I can get an ANSI stamped and approved sling from a company that makes rigging for all of the Port of Los Angeles for about $100. I actually need one thats approved at the boat hoist that I intend to use. I even have to put silly oversized backing plates behind the U bolts to prevent them from pulling through the grp. Alls I can say is the grp on these seariders is beyond rediculously thick.

Thanks again for digging up that thread.