Dinghy Hoist - added winch

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deising
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Dinghy Hoist - added winch

Post by deising »

I don’t know about the rest of you, but my dinghy and 9.9 four-stroke engine have gotten quite a bit heavier over the 9 years I have owned them. :wink: Hoisting the after end of the dinghy with the weight of the engine got progressively harder over time, but putting brand new line on the 6-part tackle made a big difference in reducing friction, for a year or so. It, again, became harder than I want, so I looked to a solution.

While some will argue it is not the best idea, I have always carried the dinghy with the engine mounted because I am not interested in the extra hassle of dismounting and remounting the engine each time we need to launch the dinghy for use. For one thing, each time you do that, it is a chance for something bad to happen (like dropping the engine overboard). For another thing, if something is a pain to do, you are less likely to do it. I would not hoist the engine on the dinghy if I had doubts about the integrity of the davit system, and I always take those few extra minutes to secure the dinghy with cross-tied ratchet straps. I don’t want to test the davit strength by adding any dynamic loads. We have cruised over 16K nm so far and sometimes in pretty rough seas, so my confidence continues to be rewarded.

As to the solution, I decided to add a small drum winch to handle the (estimated) 50 lbs. of tension in the hoisting tackle. Even though the tackle is 6:1, the friction reduces its mechanical advantage by more than you think. I knew that without a self-tailing winch, I needed to move the current cam cleat in-line from the upper lifting block on the davit to the winch drum. This way it would hold the line even when I stopped grinding or tailing the line. I fabricated some sturdy brackets and attached it securely to the top of the thick Starboard bench seat backrest.

The winch itself is secured to the port armrest of the bench with a Starboard base. It was available in custom-cut sizes (length and width) up to 1 inch thick, so I needed to get two to raise it up enough for a fair lead of the line over the bench seat backrest. Cutting the angle (needed to ensure the line fed onto the drum properly) was not easy with a hacksaw, but I was able to true it up sufficiently with a belt sander that with the cut side down, you cannot tell is was not milled.

The bolts holding the winch are perpendicular to the upper surface of the base block, of course, so they exit the bottom of the armrest at an angle. I was able to cut some angled shims from the Starboard so that the fender washers and nuts seat properly. I positioned the winch so that an 8-inch handle with a meaty hand would clear the davit arm while grinding.

My dinghy is on the dock for probably a few months while I attend to other things on the boat (seasons here in southwest FL are backwards – not much cruising in the often brutally hot summer). To test it, I stood on the beefy spreader bar that attaches to the dinghy stern and let my wife hoist me a few feet. I even bounced a few times and was very pleased with how solid it all is.

Now that I have gone to the expense ($162) and effort, I am counting on some of you to suggest much better ways that I never thought of. :)
dinghy davit winch hoist - Copy.jpg
winch and angled mounting base - Copy.jpg
cam cleat on homemade supports - Copy.jpg
Duane Ising
m/v Diva Di
Punta Gorda, FL
2006 PDQ MV 34 - hull 91, 75HP, 3-blade
AlanH
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Re: Dinghy Hoist - added winch

Post by AlanH »

Duane,

First, let me say I am not going to be the guy to say we have done something better to ease use of the dinghy. In fact, I have done nothing except continue to struggle with the same problem of raising the aft end of the dinghy with a 10hp motor.

I think your modification is well thought out and should make life a lot easier. I do have one concern and wanted to get your thoughts. The cam cleat on the backrest of the bench looks like a potential weak link. It is relying entirely on the parts you fabricated and the starboard seat back. It seems like the constant movement when cruising could weaken the starboard potentially causing it to fail.

If you have any concerns, I have a couple of ideas. Perhaps adding some bracing to the bench back would reduce risk. Also, bracing under the armrest where there is already one SS tube might work with a self-tailing winch ($$$).

You have definitely done a nice job and got me thinking about how to make raising the dinghy easier.

Alan
Alan Hendry
Catbo
2006 34' Hull #81
75hp engines
deising
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Re: Dinghy Hoist - added winch

Post by deising »

Thanks, Alan.

I did not articulate it, but my thought was to add a cleat to the horizontal rail outboard of the armrest. When done hoisting, I would keep 3 turns of line on the winch drum and then tightly cleat off the tail end. If the cam cleat or its mounting went into sudden failure, the winch and cleat would easily hold the load.

Of course, I will be monitoring the cam cleat and its attachment carefully to (hopefully) gain confidence that it is secure. Keep in mind, again, that the load on that line at the cleat is not more than 50 lbs. Starboard is tough stuff and 1/4 inch diameter fasteners tight in their holes should be fine. Still, worth watching, of course. Your thoughts for making that even stronger are spot on, but I'll observe a while before deciding if more strength is really needed.

If you or anyone decided to mimic what I did, I can supply part numbers.
Duane Ising
m/v Diva Di
Punta Gorda, FL
2006 PDQ MV 34 - hull 91, 75HP, 3-blade
AlanH
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Re: Dinghy Hoist - added winch

Post by AlanH »

Duane,

I may contact you at some point for the part number information. Right now I am just going to do a bit of thinking. Our boat has a dinghy engine hoist that may give me a way to add a winch to the engine hoist line (which also uses 6-1 tackle) to lift the boat. Then snug the dinghy hoist line and use the existing cam cleat to lock things in place. I will be sure to post if I move forward with anything.

Thanks for getting me thinking.

Alan
Alan Hendry
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2006 34' Hull #81
75hp engines
Expatriate
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Re: Dinghy Hoist - added winch

Post by Expatriate »

Duane,

Thanks for this, and especially the pictures. We did a similar thing on our old sailboat. We ran the engine hoist lines directly to a jib sheet winch. The ratio was one to one, but the winch was so powerful, a Lewmar 44, that it did not matter. It was quick and easy. After that, hoisting up the dink without motor was a snap.

We have been considering a similar approach, but have not gotten around to it. The idea of the dink with a 15 hp engine on it on the davits gives me pause, especially in the ocean. We never hoist the dink with the outboard, but might do it in an anchorage where theft might be a problem. In the ocean, even though we have a reinforced davit system, no way. It is not something I want to deal with in the gulf stream.

Once we get the outboard up, the dink is a piece of cake. So I am thinking of installing a winch for the outboard hoist. I will post pictures when I get it installed. Currently we have a St. Croix "little crane" for the motor. It could take a little head scratching.

Again, thanks for the post.

Tim
M/V 068 Expatriate
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