What is this block at the bottom of my topping lift?

[andre.leblanc]

Hey there, I'm hoping someone can help me understand what this block is used for at the bottom of my topping lift.

The topping lift is pretty standard, it runs from the unidentified block to a sheave at the top of the mast and down to a cleat at the bottom of the mast. The line around the block runs through the boom and is tied off to a cleat on the mast. It seems like adjusting either has the same affect of raising/lowering the boom.

I'm replacing the topping lift line since it looks a little weathered and was thinking about removing that secondary line altogether unless there's a good reason to have it.

[Shrew]

To raise and lower the boom. Do a search on "Rigging a Topping Lift", and you will find many examples.

[andre.leblanc]

I think I understand the rationale now. It's hard to adjust the topping lift because it comes down on the same side as the main halyard - so it's hard to use the winch and then cleat it. The line with the block that goes through the boom has a separate winch and clutch which makes it really easy to adjust. I think it just comes down to convenience which I think I'll tolerate even though it's slightly more complex with the additional line and block.

[psk125]

Definitely convenience. Would you like to schlepp to the mast every time you want to adjust the boom height? It's a lot easier to be able to reach it from the cockpit. Plus, the 2:1 setup makes it so you don't really need a winch to do it; it's quicker.

[Hudson Force]

It appears that you have an added anti-chafing material at the top of your bimini where the boom rubs against it while the main is furled. Some people keep a second position for the line through this topping lift block in order to raise the boom away from the bimini.

[LittleWing77]

Originally Posted by Hudson Force

It appears that you have an added anti-chafing material at the top of your bimini where the boom rubs against it while the main is furled. Some people keep a second position for the line through this topping lift block in order to raise the boom away from the bimini.

What Hudson said.

The way you have the boom set in your picture actually looks as if it's too low. If it were me, I'd hoick it up a bit so that it's not touching your bimini at all.

Fair winds,
LittleWing77

[Pete7]

We had that system plus a normal topping lift. I got rid of it as its one more halyard to rub on the leech. We have the advantage the boom sits on the telescopic vang when the main is furled.

Pete

[LittleWing77]

Originally Posted by Pete7

We had that system plus a normal topping lift. I got rid of it as its one more halyard to rub on the leech. We have the advantage the boom sits on the telescopic vang when the main is furled.

Ooo cool, Pete!

Yeah, in general, I don't like much like topping lifts. Yet another thing that can potentially foul the main when you're trying to get it up or down - as well as something that new-ish sailors often forget about.

LW77

[skipgundlach]

Ours looks like that except for a cheek block right below, on the side of the boom, and a fixed cable to the top of the mast.

That cheek block leads forward to a cleat at the front of the boom. A loop over the forward ear, a pull on the catenary (the line leading forward, grasped similar to sweating a line), and the boom is up however much. I cleat it off at the desired height.

In our case, we have a boom crutch, so this is used to raise it and make sure there's clearance on a tack or jibe that it won't contact.

If you were going to use it to control the amount of belly your sail had, it would be a great deal more convenient to have a line at the mast area (front of the boom). We specified our sail such that it would not touch the boom crutch, so we didn't have any bottom-end issues. YMMV in that regard.

What are the other lines?

[Kd9truck]

I have a topping lift that does not have a two part block and is ran down the inside of the mast and to the companion way and though a snatch block. I can raise the boom, control the boom Vang and control all line forward when the Bimini and dodger are up.
Not really sure there is a need for the 2 part line, not that it’s bad.

[David B]

Originally Posted by psk125

Definitely convenience. Would you like to schlepp to the mast every time you want to adjust the boom height? It's a lot easier to be able to reach it from the cockpit. Plus, the 2:1 setup makes it so you don't really need a winch to do it; it's quicker.

"The topping lift ... runs from the unidentified block ... and down to a cleat at the ... mast"
"The line around the block runs .... and is tied off to a cleat on the mast"

The guy needs to walk to his mast to adjust either line.

[Bowdrie]

Yes, topping lifts can be a pita.
That said, the arrangement that I copied from Hal Roth is hard to beat, he described/shows it in one of his books.
Since your boom appears to have a set-up where a single line is secured to some kind of fitting at the mast head, converting to Hal's arrangement is not hard.
In essence; The fitting at the masthead has a block attached to it.
The topping lift runs from the end of the boom, up to that block, and then comes down parallel to the backstay.
On the backstay rides a block, not too high-up, close enough to easily work on.
The topping lift is secured to that block.
Another block, with a becket, is at, or near the deck.
The control line for tension runs from the becket of the lower block, up and around the sheave of the "riding block", back down thru the sheave on the lower block,, thence to a cleat positioned to your liking.
You get a 2:1 purchase that can be operated from the helm, (or close by,) you eliminate extra lines on the mast and boom
It's not hard to rig-up the riding block with a bit of ingenuity, and it won't chafe the backstay.
You can also switch around blocks and beckets to arrive at leads and ratios to your liking.
In some kind of emergency you can lower the boom to the deck, disconnect the lift from the boom and riding block and have a halyard, or use the topping lift to pull a bigger line thru the masthead block.
Been using Hal's arrangement for over 25 years, it works better than anything else I've used,, except for a rigid vang.

[rpjn59]

My guess is the set up down the mast to a cleat was provided later. My older '66 has the same boom configuration but stops at the mast head with a crimped cable and pin to secure it.