Rigging on davits

Ok this is driving me crazy . Why are these blocks twisting 90 degrees to each other ? I have swivels on each end . Do I need to remove one ? On the side that has the double block at the top the line wants to climb out of the sheave .

lol, been there and just as confused until I realized what was happening. You have 2 sheeves up top, the load comes in from one side. On the top pulley in the stern of the dink the line comes in from the Davit towards the front of the dink, that is why it is tilted to the port of the big boat.
Purchase a 3 sheeve block and route the line symmetrical through the center one first.

Also, on the blocks towards the bow of the dink, the top block is being pulled towards the starboard side of the dink. This means that the line leading down to the lower block is also being pulled to the starboard side. This is causing that lower block to rotate in that direction.

Are you using a capstan or a sheet winch to hoist? If so once in a while you have to unreeve the lines and unwind them. Constantly turning in one direction under load makes the lines twist in clockwise fashion. If you have the chance, if this is on a capstan that powers in both directions wind it counterclockwise once in a while when hauling dinghy. Braided lines can get hockles in them contrary to conventional thinking.

It's not the blocks that have the issue. It's the line.

Endlessly annoying to re-reeve blocks until they learn some manners. Been there, done that.

The pick up points on the davits are about 12" closer together than the pick up points on the dink. I thought about making a spreader bar and attach it to the davits and get my pick up points at the same distance apart . Will this make the blocks stay in line and not twist 90 degrees from each other or can I fix it with more blocks . We are raising and lowering by hand .

I don't think that would make a difference Marty. As was mentioned, you may want to check line twist, I had considered that, but unless it was pretty bad I don't think it would cause as much twisting as you are experiencing.

Those are nice wooden blocks, but if you want the twist to go away, you can always use a fiddle block.


These would eliminate the twist and you can get as much purchase as you like. The double fiddle block with becket above would go where your upper double block is on the stern. A single block with becket would go below it. That Lewmar block from Defender is only $38 and will take a 5/16" double braid line.

Or find someone like me with lots of old sailing gear in their basement and scrounge for it. The other option is if you have a chandlery in your area that caries used gear.

This shows the difference in the distance between pick up points . The top block seems to splay more than the bottom and the position of the cleats on the davits is even closer . Once it starts to climb out of the sheave it's almost impossible to get the dink up as high as I want it . Joy is starting to loose interest in a nice dinghy ride .

Since your problem is the upper block twisting out of line, the very first thing I would try is simply remove that swivel connecting the block to the davit arm. I can see no valid reason for that swivel being there in the first place!
You might at the same time gain a bit of extra lifting height, enabling you to snug the dinghy right up to the davits.

I have 4:1 purchase on my davit falls. I redesigned the rig a little to allow me to replace the upper block with a double, fixed cheek block. It does not swivel at all, of course, and I have no trouble with this arrangement.
So, taking the swivel out may solve your problem.
By the way, lovely dinghy! - what brand and model?

Thanks for the suggestions everyone .

dhays I got those old blocks from our own FF right here on TF along with some heavy duty big bronze cleats .

SlowGypsy the dink is an older Trinka 10 ft .

My davit mfr, Ocean Marine Systems Ocean Marine Systems - Davits, Rails, Lifts, and Platforms. insisted that my davit falls be out of line, like you have yours, so that the dink can be pulled up tight and have less inclination to flop around. He stated that the higher part of the load on the system is dynamic and that it's important to have the dink move as one with the boat.

The swivels are not helping. The top blocks should just have a shackle. The bottom should just have the snap shackle. No swivels. The purpose of swivels under load is to let the load rotate. There is no need to let the dinghy rotate at all.

Since you pull this up by hand, do you lower it with a wrap around a cleat on both sides?

If so, when you make the line fast turn the first round turn of the line the opposite of the way you currently do. Running a line out under tension around a cleat puts twists in line also. (Same thing why anchor Rhodes get full of Hockles).

The way I am taught to reeve blocks like your double set, is that they are supposed to be aligned at 90 degrees to each other.

What was this line used for in its previous life? Is this an old anchor rhode? Or a roller furler line? Something that was constantly wrapped under tension on a winch?

I think this was an old genoa sheet line from my
sailboat. Sounds like I probably need two new 7/16 " lines with thimbles so I don't have to tie it to the blocks , then remove at least one of the swivels from each side .

Try rigging the falls differently .

Look in Chapmans

I removed all four swivels . No binding or twisted lines now . I plan on buying some new line with a small eye splice in one end to hook to the blocks so I can get rid of the knot . Thanks for all the help . This made huge difference. The blocks are still canted some but the stay in line with each other .

I'm thinking about going to a 6 to1 purchase for each side of my davits. Joy and I are struggling when hoisting the dinghy plus I'm going to add a motor to the dinghy this year. I'm thinking total weight will be around 200lbs. I don't really have a place for a winch so I want to stay with blocks and I have plenty of new 7/16" line. Buying four new three sheave blocks is quite an expensive commitment. Are any of you set up with a 6 to 1 purchase or something similar?

can you rig a centered mounted winch and turning blocks?


then you don't need a purchase advantage and I find winches easier and smoother.

psneeld said:

can you rig a centered mounted winch and turning blocks?


then you don't need a purchase advantage and I find winches easier and smoother.

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Hmm I have a small sailboat winch , it’s not self tailing and I’m not sure I could mount it without doing some welding on the davits. Do you think the one winch would be enough? Would it just need two blocks?

Pack Mule said:

Hmm I have a small sailboat winch , it’s not self tailing and I’m not sure I could mount it without doing some welding on the davits. Do you think the one winch would be enough? Would it just need two blocks?

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in the middle with the two leads in different directions will work coming up...but a non electric power both ways might not work.


if the lift isn't too high, then one side at a time might work....winch mounted in the middle.....no necessarily welded.

Pack Mule said:

Ok this is driving me crazy . Why are these blocks twisting 90 degrees to each other ? I have swivels on each end . Do I need to remove one ? On the side that has the double block at the top the line wants to climb out of the sheave .

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I would take out the swivels and shackles and just bolt ( not too tight but tight enough ) the blocks to the Davits.



My .02 CAD

Ex Sailor said:

I would take out the swivels and shackles and just bolt ( not too tight but tight enough ) the blocks to the Davits.



My .02 CAD

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I’ve removed all the swivels and replace the lines with new. It works much better now but still too much of a lift for my wife and I . Looking to lighten the load now.

These are the blocks I’m looking at for each side. Over kill or about right ? Dinghy weight is about 200 lbs with motor.

In an earlier post I mentioned the way to reeve the blocks so they don’t twist under both load and no load. It works. But you MUST reeve them correctly.

https://www.harken.com/content.aspx?id=3901

The rule of thumb for blocks is: The larger the sheave diameter is proportional to the lessened friction. And the better quality blocks with better bearings. Sorry. Can’t help with which is quality and which is not.

It’s been 20 years since I had to buy blocks. But definitely Don’t get ones with delrin or nylon bearings. Stainless or bronze bearing/bushing only.

Dont forget to determine, if the blocks will permit raising the small boat properly to its "up" position.
Also, a 6 to 1 block system will take a whole more line than a 4 to 1. You will be using only 2 blocks lifting the boat from the center point???

May I encourage you to look around at existing davit systems.... you may get some better ideas incorporating an electric winch. No need to work up a sweat putting the boat into the water and taking it out of the water.

Consider weaver davits and only lifting the outboard side. But this only works on swim platform. And as Dan says: You could probably get away with 4 to 1 on the bow, and 6 to 1 on the outboard end. The weight is not exactly divided in half. It’s more like 1/3, 2/3.

cappy208 said:

Consider weaver davits and only lifting the outboard side. But this only works on swim platform. And as Dan says: You could probably get away with 4 to 1 on the bow, and 6 to 1 on the outboard end. The weight is not exactly divided in half. It’s more like 1/3, 2/3.

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We don’t have a swim platform . What we have is working ok and even better since I removed all the swivels. I like the set up I just want to make sure that adding more sheaves is worth the bang for the buck.

cappy208 said:

Consider weaver davits and only lifting the outboard side. But this only works on swim platform. And as Dan says: You could probably get away with 4 to 1 on the bow, and 6 to 1 on the outboard end. The weight is not exactly divided in half. It’s more like 1/3, 2/3.

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If you go with an electric lift, anchor point for and aft, lifting from the center balance point, you can avoid the blocks.
Again, look around the marina and see how some other folks handle this. Ideas and advice are free.
Just how big is your outboard?

Pack Mule said:

We don’t have a swim platform . What we have is working ok and even better since I removed all the swivels. I like the set up I just want to make sure that adding more sheaves is worth the bang for the buck.

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Just buy one set. Use it on the stern end. The stern end is heavier. (Much more so with the outboard).