Should a mizzen be straight? Or raked aft. And mainmast forestay tension

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steve yates

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My longbow mizzen mast has two shrouds each side, one pair slightly, and I mean slightly forward of the mast.
I've tightened that up but the mast rakes aft about 15degrees. I haven't tightened the other pair very much as I don't want to rake it back any further.

It does have a triatic stay to the mainmast, which has to be attached yet, but everything I have read on these ( not much) suggests that should not be over tight. Is it the triatic job to straighten the mast? Or the the forward of the shroud pairs? Or is a rake aft normal? The main,sat is not raked. ( boat is for cruising, not racing)

The main reason I ask is I need to go up that mizzen to rig the triatic :) and I don't want the bloody thing coming down on me.( Just in case I will rig a warp from it to the mainmast while I go up.)

On the forestay, how tight should I be able to get that? I am assuming the forestaytension is controlled by the backstays? (Mines are split) Its a roller furling set up.
The Genoa halyard has jumped off the sheave at the masthead, so I will be going up there too to sort that out, anything else I should look at/do/add to improve a furling Genoa system while I'm up there? Will spray the sheaves with silicone spray, but that's all I can think of.
Thx.
 
The Westerly Owners Association is your best bet with this. You don't have to join in order to get advice, though it's very reasonable to do so. It really is a goldmine of Westerly knowledge.
 
steve yates said:
My longbow mizzen mast has two shrouds each side, one pair slightly, and I mean slightly forward of the mast.
I've tightened that up but the mast rakes aft about 15degrees. I haven't tightened the other pair very much as I don't want to rake it back any further.

It does have a triatic stay to the mainmast, which has to be attached yet, but everything I have read on these ( not much) suggests that should not be over tight. Is it the triatic job to straighten the mast? Or the the forward of the shroud pairs? Or is a rake aft normal? The main,sat is not raked. ( boat is for cruising, not racing)

The main reason I ask is I need to go up that mizzen to rig the triatic :) and I don't want the bloody thing coming down on me.( Just in case I will rig a warp from it to the mainmast while I go up.)

On the forestay, how tight should I be able to get that? I am assuming the forestaytension is controlled by the backstays? (Mines are split) Its a roller furling set up.
The Genoa halyard has jumped off the sheave at the masthead, so I will be going up there too to sort that out, anything else I should look at/do/add to improve a furling Genoa system while I'm up there? Will spray the sheaves with silicone spray, but that's all I can think of.
Thx.
Click to expand...

Looking at pictures on line it does appear that the mizzen mast is raked aft.

I would start by setting the main mast up vertical with everything correctly adjusted and tensioned.

I would set the mizzen up with less that the expected amount of rake, attach the triatic stay and then adjust the rake to put a little tension on the triatic. The angle is such that you you wont easily put much tension on it

A good idea to arrange some additional support for the mizzen, as you suggest, while you go up it to attach the triatic, especially with the rake and shroud geometry you describe.


The person who would have answered your questions was Searush as he has a Pentland ketch, but he appears to have defected totally to " not the lounge". You could try joining NTL or you could try the Westerly Owners Forum, where Searush posts under his own name, ( SA Kean) or even the WOA Yahoo group


I would investigate the reason why/ how the genoa halyard has jumped off the sheave. I don't believe that should be possible!
 
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I have a ketch. If you have the mizzen set at a different angle of rake from that of the mainmast, it will look b***** awful.
 
NormanS said:
I have a ketch. If you have the mizzen set at a different angle of rake from that of the mainmast, it will look b***** awful.
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Reaper_in_sail.jpg


(Actually I agree with you.)
 
I have a Renown next to me in the marina that has recently been re-rigged by XW Rigging who are Westerly specialists. I will have a look at it when I am down in the marina tomorrow and try and answer your questions.
 
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The drawing in the original Westely sales brochure shows the mizzen mast to be more or less parallel to the main mast, so I'd guess this was Westerly's intention.

View attachment 63864

I used to own a Pentland ketch, and the masts were more or less parallel on that - certainly not a 15 degree rake.
 
It should be straight, Steve, both masts parallel. I've replied to this on the Westerly Forum directing you to more pictures.
Somebody has really been bu@@ering about with your boat. There are 4 sheaves at the top of the mast, 2 for the main and 2 for the foresai with a metal plate over them which the vhf aerial and mast head lights are fitted together with wind arrow and anything else up there. They run the width of the mast, 2 at the front and 2 at the back. The halyards go over the first sheave, across the mast centre, over the second sheave and then down the mast to a cleat near the bottom. How the genoa halyard has jumped off 2 sheaves with a metal plate over the top of them is beyond me. I can only assume that someone has threaded the foresail halyard through the spinaker sheave. The only other option is if someone has tried to run the halyards down the inside of the mast and carved holes in the base of the mast.
On the Westerly site somewhere I think its the wiki, there are the original brochures and a triasic isn't shown on the drawings. As can be seen in Pete's drawing above.
Mike
 
Vegable said:
On the Westerly site somewhere I think its the wiki, there are the original brochures and a triasic isn't shown on the drawings. As can be seen in Pete's drawing above.
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Good point! There was no triatic on my Pentland ketch. Sounds like someone has messed about with the rigging.
 
Thanks all, I'll ask the po when the triatic was introduced, should see him next week.
In that sketch Pete it looks to me that the mizzen has a slight rake aft compared to the main,ast?
Granted it's not 15 degrees, but I'm sure it shouldn't be that, and will try and adjust for it when back up next week and the triatic is attached.
 
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>It does have a triatic stay to the mainmast, which has to be attached yet, but everything I have read on these ( not much) suggests that should not be over tight. Is it the triatic job to straighten the mast?

The Triatic stay should be as tight as the rigging and the mast straight, if you have bottle screws climb the main mast to tighten it not the mizzen.
 
A triatic stay often starts at the head of the mainmast, then passes over a sheave mounted at the front of the head of the mizzen mast, then down the front of the mizzen mast to a point where the bottlescrew is accessible.
 
Hi Steve

I had a good look at my neighbours Renown today, he was on board, so I gave him a copy of your original post and will try and respond on the forum.

Basically both mast are rigged independently, there's no triatic, the mizzen getting its forward support from jumpers on the mast. The main is raked slightly, perhaps three or four degrees, and the mizzen is at the same angle. I hope this helps; I am assuming the Renown and Longbow ketches have the same rig.

I would set up the main according to the instructions on the Selden website, and then rig the mizzen so as to be parallel with it.
 
steve yates said:
My longbow mizzen mast has two shrouds each side, one pair slightly, and I mean slightly forward of the mast.......
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That just sounds wrong to me.
There will be huge loads on those shrouds from sheet tension.
Are the shrouds to the mizzen masthead?
Have the chain plates been moved?
Or the mast step?
 
Hi Steve

The shrouds on the mizzen stop somewhat short of the masthead, it's from that point that the jumpers take over. My neighbour, whose boat has been in the family for about 40 years, thinks the very early boats did not have the jumpers.

Good Luck

Rick
 
I looked at Steves boat on the way up from the pontoon this evening, 15 degrees? he must have skipped geometry, or been elsewhere when they did angles. (there are jumpers to keep it straight all right but they do nothing to support it), but the loads (other than Steve,) will not be that great.
Jackie Kay has got his boat in the dummy lock in front of Juliet Kilo so he will be able to reassure him.
 
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>A triatic stay often starts at the head of the mainmast, then passes over a sheave mounted at the front of the head of the mizzen mast, then down the front of the mizzen mast to a point where the bottlescrew is accessible.

I've never seen that only mast to mast.
 
KellysEye said:
>A triatic stay often starts at the head of the mainmast, then passes over a sheave mounted at the front of the head of the mizzen mast, then down the front of the mizzen mast to a point where the bottlescrew is accessible.

I've never seen that only mast to mast.
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Yeah, this one is a line from the head of the mizzen mast to a block coming off the head of the mainmast, back to a block on the mizzen top then down the mast and tensioned and tied off on a mast cleat.
 
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