While waiting for the water temps to push above 40 here in Vermont, I found myself thumbing through the Layline catalog, stopping to ponder the Spinlock Power Cleats. Has anyone had any experience with them on beach cats? Seems like it might be a good solution for loaded cleats like the traveler, especially in heavy air.

i have seen boats with them retro fitted in place of the main sheet cleat. it looked like they worked well.

A fellow sailor here on Lake Champlain uses one on his mainsheet. He likes it a lot and claims it has never failed to release his main with a flick of the sheet. The application I'm also interested in is on the traveler as it seems like it would be a smoother release under load in heavy air. This year, Spinlock came out with one of the PX cleats mounted on a swivel base.

spinlock makes nice stuff. you might want to look at the ronstan c cleats. they are my favorite.

While these cleats never fail to release, I have seen them fail to engage under high load. Application was mainsheet for Antrim 27 (monohul from great mutihull designer) Couldn't get the cleat to bite (spectra core sheet) under high load conditions.

The MWL (maximum working load) spec for the PX cleat is 440, while the spec for the Harken 150 aluminum cleat is 300 and the Ronstan C-cleat is rated at 400. Anyone know what the highest load is that can be achieved on the main sheet or traveler for a typical 20' cat?

Kevin,



I expect it to be nearly 500#. I sometimes nearly give it my all, using both legs with arm stretched straight. I can leg press somewhere between 400 and 600 pounds.



GARY

Gary,



Hmm. If the load on the sheet is 500#, any of the commonly used cleats would be subject to failure . . .

Kevin,



Even if you are not applying anywhere near 500#, just think about the momentary shock loads when you get a puff, hit wave, etc.

GARY

My question was in response to Bruce Williams' comment in an earlier post, "While these [Spinlock PX] cleats never fail to release, I have seen them fail to engage under high load."



Bruce's comment prompted me to compare the Spinlock numbers with those for the popular cleats on the market (Harken and Ronstan). They all seem to be very close. I then began wondering how close to those loads we actually operate.

Experience speaks louder than numbers. I have used Harken equipment consistently above their load requirements without ever an issue. I've only approached the load numbers on Ronstat and had them blow up. I like Ronstat equipment but I don't pay any attention to their load numbers.



I would talk to sailors and not compare numbers in a catalog.



Mike Hill

H20 #791

Mike,



>> I would talk to sailors and not compare numbers in a catalog.<<



Problem is, I haven't found anyone yet who's had the experience with the PX cleat on a cat, so I have nothing to compare but the specs.



A lot of sailors on other boats seem to love the PX cleat. Real easy to cleat and uncleat. You don't have to pull the sheet while lifting to get the cleat engaged. You just lift up. To release, a flick of the sheet (same as with a cam cleat).



Before switching over, however, I was hoping to hear if any cat sailors have had experience with them, good or bad.

If you are pulling the mainsheet at 500# with a 6:1, then at the main clew the psi would be 3000#? And everything would explode? Now, if the main clew is at 500#, you would be pulling @ 83#.

John you make a good point and there are plenty of flaws in this sort of speculation, guesswork. I could also point out that there are huge frictional losses in the block and tackle. So the result at the business end is definitely not eight times the input effort.



I just realized something. Even if I were pulling at 375#, there is a hexaratchet block there. Don't those things offer a 15:1 level of reverse resistance? That means that even if the sail had 3000 pounds of pull at the clew, you would divide that by 8:1 for the block and tackle and then subtract out the inherent friction (that I will guesitmate at 10%) and then divide that result by the 15:1 holding power offered by the hexaratchet.

[(3000/8)-(.1*3000)]/15=22.5

So it looks like the cam cleats are working at about 5% of their rating. (22.5#/500#)

GARY

I tried using a spinlock on my H-18 when they first hit the market a few years ago. It was really cool for the roundup at the leeward marks. The only problem was it exploded in less than two months. It did not like the beating that a mainsheet system takes on the rear beam in light air with waves.



Spinlocks do have their applications on beach cats, just not on the mainsheet.

I currently use a small spinlock for the spin halyard on my I-20 , they last about 1 season.

Gary,



Picked up this tidbit off an article by Peter Bentley on the Sailing Pro Shop site (All About Rope).



"If it is a rope you pull on, it's a fair bet that the load will not be more than about 20kg, perhaps 50kg [110 lbs] top whack if you are a big man. Multiply this up through the various purchases and it's easy to work out what the load is at any given point. Take care though with lines that are cleated Off. It's easy to pull the kicker in with one hand when the sail is flapping but just think what the load might be when it's locked off and the boom end smacks into the back of a big wave. That's when things break."