Tips on operating the P19 Keel Winch:

The following items are excertps from my posts on the WWPotter Listserv and the Potter Forum on the TrailerSailor BBS


Using Line vs. Wire cable for the Keel Winch

I use 1/8" 7 x 19 flexible wire for the keel winch. I don't advocate using line instead of wire for the keel lifting winch. Some folks complain that their wire develops "meathooks". but Redwing's wire cable never developed "meat hooks. I replaced the original wire in 1998 or 1999, when the boat was 13 years old, even though it wasn't worn, when I removed the winch for rebuilding. I installed a new wire rope and it's been holding up just fine for the past 5 or 6 years. With proper operation, which I've discussed inumerable times on this forum, a wire cable will last decades without getting meat hooks.

And, there is one VERY, VERY important reason to use wire rather than rope on the keel winch.

The wire is VERY small diameter for its strength, and that means that you don't over fill the winch drum. The more cable you put on the winch drum, the less mechanical advantage you get. Rope fills up the drum faster than wire, because rope usually has a larger diameter.

A winch with a full drum has only 1/2 or 1/3 the mechanical advantage of a winch with an empty drum..... so with rope that's fatter than wire (which fills up the drum), it takes much more muscle to raise and lower the keel.

Wire is also VERY abrasion resistant, and not likely to wear through if you "over wrap" the cable on the drum. Line can cut through itself much more easily if there is a overwrap that starts to slip.

If you do use rope, get the thinnest, strongest line you can, so you don't fill up the drum on the winch. 1/8" 7 x 19 flexible wire cable has a breaking strength of about 1800 pounds. To get that kind of strength in a line requires, unfortunately, using pricey stuff like spectra or something similar.

... before you pick a high tech line like spectra, I'd suggest you do some research on its resistance to abrasion. It's my impression that most of those high tech lines are much less resistant to abrasion than dacron/polyester. I don't know the specs on abrasion but I don't think they're too good.

I believe the reason that high tech **cruising** lines are usually made of a high tech core, with a POLESTER COVER for UV and abrasion resistance. Rock Star Racers use spectra (and the like) lines without covers, but they don't care about durability.

But check on abrasion resistance of the most recent generation of high tech lines for yourself. Maybe they've gotten more durable since I looked into it.


How much effort does it take to raise the keel? There's something wrong with your system if it's hard to raise the keel.

I'm a 110 pound woman. I'm strong for my size but I'm certainly no amazon. And I don't find it particularly hard to raise the keel on a P19.

I have raised the keel one handed on the newer P19's. I used to do it on "Deep Blue", a 2000 (?) model, originally owned by Chris Beatty. And I've done it on several other P19s with one hand, including Jerry B's HMS18. And I've seen other P19 owners sitting on the cockpit seat, with the tiller in one hand, cranking up the keel with the other hand.

I use two hands on my 1985, Redwing, because the winch doesn't have a built in brake, and it would be dangerous if I lost my grip on the handle. It could break knuckles. It's a tiny stainless steel mechanism, (about 3" x 3" x 4") mounted on the forward cockpit bulkhead, very different from the newer ones.

And another reason to use two hands on Redwing is that her keel winch doesn't have as much mechanical advantage as the newer ones that have the Fulton K650 Braking Winch.. I have to use two hands. It's a moderate effort for me to raise the keel on Redwing, but not that hard. My hubby does it without much effort.

I can't sit and steer on my 1985 while I raise the keel. First of all, I can't reach the winch while steering. Second of all, it takes two hands to do it safely, because there's no brake on the winch. But that's never stopped me from entering shallow water. I stop, raise the keel part way, and then motor into shallow water. It works fine for me -- it only takes a minute.

I personally wouldn't spend money or time re-engineering the system so I could raise the keel while steering. It's nice if you can do it, but it's absolutely NOT a highly valuable feature for most folks, IMO.

I've got one of those Fulton K650's in my spare parts box, but I haven't ever felt pressured to installing it. I've never even gotten around to installing it.

Your mileage may vary...


Mechanical advantage of the P19 keel raising system

The keels weighs less than 300 pounds, including the keel cap. The factory system has a 48:1 mechancial advantage at its most effective (with no wraps on the drum), diminishing to 15:1 at its least effective (with a full drum).

The keel winch used on the newer P19s is a Fulton K650. see http://www.fultonperformance.com/products.php?group=77&subgroup=80 for the specification.

The first wrap on the drum gives you a 16:1 advantage, but the mechanical advantage decreases as the drum fills up with cable. When the drum is full it gives you about 5:1 advantage.

Combine the winch with the 3:1 tackle above the keel, and the mechanical advantage is between 48:1 and 15:1. With a keel under 300 pounds, you shouldn't need more than 20-30 pounds of force to crank the keel up, even allowing for a 30% loss due to friction.

If you big strong men are having trouble raising the keel on your boats, then I suspect you need to trouble shoot the system and figure out where it's binding. Inspect the blocks for damage. The OEM blocks are Harken wire blocks rated for 500 pounds safe working load (part #183), but improper operation of the keel winch can damage them. Check for fair leads on the blocks. Lubricate them annually with a good dry lube that doesn't attract dust (my favorite dry lube is Harken's McLube, but TriLube from the bicycle store is good too)

Or maybe you have too much cable (or fat rope) on the drum, which reduces the mechanical advantage very quickly. (The mechanical advantage decreases as you wrap more and more cable onto the drum). Alot of people have converted to rope thicker than the 1/8" wire that comes with the winch. That's not a good idea. With proper care, the original wire cable on my P19 Redwing lasted over 15 years without getting meathooks in it. I replaced it when it was 15 years old just for the heck of it. After 5 years, it still looks and feels like new.


 

Always lower the keel so the support bolts are resting on the keel trunk before storing the boat or trailering it.

Fiberglass is plastic. Don't store your boat with the weight of the keel hanging on the cable. Leaving the weight of the keel on the cable will deform the cabin top over time. Don't do that to a boat you love!!!! Lower the keel completely so it's resting on the support bolts when it's in storage or on the trailer.

Here's a cautionary tale: In spring of 2004, I received an email from a fellow who had a problem with his P19 . The top of the cabin had dropped nearly an inch. The teak strips on either side had pulled out. He couldn't close his hatch. He had left it in outdoor storage for several years under a cover. He lives in a part of North Carolina where the temperature often exceeds 100 degrees.

The first two things that came to my mind were a) he had left the weight of the keel hanging from the roof on the cable or 2) he had a really serious case of core rot AND he had left the keel hanging on the cable.

My first question to him was "was the keel hanging from the roof?" His chagrinned answer was "yes". He hadn't lowered it so the weight was resting on the keel trunk.

I asked him to send me pictures so I could see with my own eyes what he was talking about. Here's a picture:

 

I suggested that he first rule out the possiblility of core rot by inspecting the core (removing the through bolts for the cable lift blocks over the keel). If the core was intact, I suggested he remove or lower the keel, put a jack on the top the keel trunk, and slowly, over several days or weeks, jack up the coach roof to remove the "dent". I hope it works. If he writes back, I'll let folks know if it worked.

After talking to that unhappy fellow, I tried an experiment with the keel on my 1985 P19, Redwing. I cranked up the keel then lowered it so the support bolts were touching the keel trunk, but with most of the weight still supported by the cable. The cable was as tight as a piano string. The coach top was deflected down a small fraction of an inch, bending the wood sliders slightly. The sliding hatch didn't slide easily; I really had to bang on it to get it to open or close. As soon as I released the tension on the cable and allowed the full weight of the keel to rest on the keel trunk, the deflection disappeared, and the hatch slid easily, just like it always did.

So, here's my reminder: Be sure you lower the keel so the support bolts rest on the keel trunk when you trailer or store the boat. Be sure ALL the weight is supported by the keel trunk, with none on the keel cable.

After completely lowering the keel so the cable is slack, take up the slack just enough so the cable will stay in the center of the blocks, with no appreciable tension on the cable. Don't leave the cable floppy loose either, because you might get an overwrap when you go to lower the keel next time -- and that'll cause the keel to drop suddenly, damaging blocs, the cabintop and possibly causing injury to the operator.


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