# Farr Ims 40.7 and possibility of putting aft swept back wire?



## thenzsea (May 8, 2012)

I had dismasted Farr 40.7 Ims during race and will get it reconected.

However I want to make standing rigging stronger by putting additional wire to pull the mast back like runner does.
(I will also use runner as well)

Would you give me advise for my thinking which is like below?


1. to make eyes around the position where runner attached on a mast

2. to attach wire on both derection (port and starboard) 

3. to pull it back to a meter back of side stay turnbuckle on the deck?

(putting 7 shape chain plate on deck and side hull)



I assume that it's not good for her performance, 

however If it's not biggey, I rather do it for safty.


Please give me advise in details


----------



## Jeff_H (Feb 26, 2000)

This is a question to address to Bruce Farr's Office, which has been great at providing customer support on their past models. I know the Farr designed Beneteau 40.7 pretty well. The idea itself really does not make any sense, at least as you have written it. 

Jeff


----------



## thenzsea (May 8, 2012)

Thank you ~
Would you explain more detail why its nonsense?

I had dismasted by mistake of runner backstay.
I want to make sure even if samething happen in future, keep the mast safe by putting additional permernant stay back like reserve runner!

If its not good idea, what would be better?
Kind regards,
Sun from Korea


----------



## thenzsea (May 8, 2012)

Bytheway I sent a email to Farr design office as well ^~


----------



## SchockT (May 21, 2012)

Thenzsea, I assume you are not talking about a Beneteau 40.7 (designed by Farr) since they don't have running backstays. You are talking about a 1990's era Farr IMS 40 which does indeed have running backstays. Is that correct?

If that is the case, what you want is a single permanent backstay on centerline like a traditional backstay. The problem is that if you may have clearance problems with the roach of the main. The problem can be reduced by installing a batten at the masthead that will lift the backstay up when it is eased to help the sail clear the stay. It is sometimes referred to as a "flicker". Depending on the cut of your mainsail it may only be a problem in light air.

I can't think of anywhere else you could install a permanent stay where it would be at all effective. I suppose another possibility could be if your existing backstays can clear the main, then you can make them permanent, and just have running checkstays alone.

That is the problem with race boats that depend on running backstays and checkstays to keep the mast up! There is no room for mistakes!

I would talk to your local rigger about installing a permanent backstay, or other options. rather than doing it yourself. As you probably know, dropping your mast again is expensive and dangerous!


----------



## thenzsea (May 8, 2012)

Hi SchockT,

Yes It is Farr 40.7 IMS (1993) with running backstays built in NZ.

As your recomendation, I was thinking about permanant backstay but the top of mast is so flexible that it wouldn't help to keep it upright. 

The tentionest part in downwind is the place around the running backstay attached on mast so I thought to put permanant stays there from.

I would like to know even if sacrify her performance, will it do the job like running backstay when it's mistaken?
Would you belive in there is no yacht rigger specialty here in Korean?
I am asking around to get some idea for that and in next week,
I will get some boat workers to do that job!

I asked to farr design office about reconnecting mast 
(by reveting & wellding after putting additional aluminium inside and outside)
and this question! 
They just said "buy new one!" that's all !


----------



## SchockT (May 21, 2012)

A permanent backstay to the masthead on a fractional rig to complement the running backstays is not uncommon. Don't mistake "flexible" for "weak"! Just because your mast tip is bendy doesn't mean it will break. It will easily hold the mast up! Of course you can break the top of the mast if you really load it up. On the drawings I am looking at for the IMS 40 it appears to show a masthead backstay already. Is that not the case on your boat?

Farr IMS 40

As for repairing a mast, what you are describing is called "sleeving" and it is acceptable on cruising masts. On a flexible racing mast like yours it depends on where the break was, because that repair area could change the bend characteristics of the mast in a big way. Most race boats would opt for replacing the mast section for that reason, but they are also covered by insurance.

Another option for stabilizing your mast might be to relocate your chainplates aft, and sweeping your spreaders aft. I had a small race boat with a very bendy fractional rig, and it didn't need a backstay at all due to the aft swept spreaders. Of course it was a much simpler mast than what you have.

Keep in mind I am not a rigger, I am simply relating mast configurations that I have sailed with in the past. What you have is a very complicated high performance mast. Unless you really know what you are doing, be very careful what kind of modifications you do! It is unfortunate that you do not have any professional riggers in your area. Are there no high level racing teams in korea that could tell you who to talk to?

P.s. If you do end up buying a new mast, I have heard of people retrofitting the old IMS 40 mast with the newer and simpler Farr 40 rig.

Of course you could just train your crew better! Especially the runner guy!


----------



## SchockT (May 21, 2012)

Is this like your boat? You must have alot of fun with that machine!


----------



## SchockT (May 21, 2012)

thenzsea said:


> Hi SchockT,
> 
> The tentionest part in downwind is the place around the running backstay attached on mast so I thought to put permanant stays there from.
> 
> ...


You can't have permanent stays below masthead without interfering with your main. Even if you had them in very close to the mast at a steep angle, they would still be in the way, and the kinds of loads you could be putting on those stays at that angle would require some serious engineering for chainplates. You couldn't put that kind of load onto your deck alone. Even if you did do that and were prepared to live with the boom interference, the damage you could do to the rig if the boom hit it hard in a wipeout?

It's a bad idea, and it would ruin that beautiful boat of yours!

I am curious, where did the mast break, and what were the sailing conditions? Do you have any pictures? I notice this one has a permanent backstay.


----------



## thenzsea (May 8, 2012)

Thanks a lot SchockT,

I will put more pics of her on my profile!
So you recomend to put permanant centeral backstay, don't you?
I would seriously think about that again!
At the moment I got no time to ask more about but get back to you soon tomorow!

Thanks again ^^


----------



## puddinlegs (Jul 5, 2006)

SchockT said:


> Another option for stabilizing your mast might be to relocate your chainplates aft, and sweeping your spreaders aft. I had a small race boat with a very bendy fractional rig, and it didn't need a backstay at all due to the aft swept spreaders. Of course it was a much simpler mast than what you have.
> 
> P.s. If you do end up buying a new mast, I have heard of people retrofitting the old IMS 40 mast with the newer and simpler Farr 40 rig.
> 
> Of course you could just train your crew better! Especially the runner guy!


If its the sail plan illustrated in the drawing, because of the jumpers at the top, it looks more like the 39 M/L. If so, there's nothing that a backstay will do other than open up the top of the main. There's no way to 'stiffen' the top of the rig. It's a great and very tweaky rig, but not one for anything less than an experienced crew. You need two runner guys in any sort of breeze, always, no exceptions.

The 'PS' part might be the best solution, but in any case, there's going to a lot of cost to make the structural changes (chain plate location, etc..) that are necessary. You might want to contact Hallspar or a similar spar maker and see what a new rig with swept back spreaders, etc... might cost. Honestly, I think the Farr office's answer was the correct one.


----------



## SchockT (May 21, 2012)

I agree. Redesigning a rig on a boat like that is not a project for the inexperienced. All you would do is destroy the resale value of the boat along with the performance.

No matter what you do, there will always be a risk of breaking that mast if you and your crew don't know what they are doing. Even experienced race teams break their masts; big budget teams even have spares!


----------



## thenzsea (May 8, 2012)

puddinlegs said:


> If its the sail plan illustrated in the drawing, because of the jumpers at the top, it looks more like the 39 M/L. If so, there's nothing that a backstay will do other than open up the top of the main. There's no way to 'stiffen' the top of the rig.


Thank you and 3 questions?

1. Jumpers? You mean wires like stays at the top?
2. Even if I put Permanent backstay, wouldn't it be helpful for making rig 
stronger?
3. Openning up the top of the main means that when I pull the backstay
it just help to twist (=open) the main. isn't it related to move the
draft back of sail that help for beating?


----------



## thenzsea (May 8, 2012)

SchockT said:


> I agree. Redesigning a rig on a boat like that is not a project for the inexperienced. All you would do is destroy the resale value of the boat along with the performance.
> 
> No matter what you do, there will always be a risk of breaking that mast if you and your crew don't know what they are doing. Even experienced race teams break their masts; big budget teams even have spares!


Yes, I will take your advise not to redesign the rigs and will do more trainning before next race 

Someday When you have chance to visit Korea, hope to sail together ^^


----------



## SchockT (May 21, 2012)

thenzsea said:


> Thank you and 3 questions?
> 
> 1. Jumpers? You mean wires like stays at the top?
> 2. Even if I put Permanent backstay, wouldn't it be helpful for making rig
> ...


The masthead backstay on your rig primarily serves as a mast bending tool. Bending the mast flattens the mainsail. Bending the mast will also twist off the top of the sail if you don't compensate with more sheet tension. The permanent backstay will prevent your mast from falling down in the absence of the runners, but it will not make it stronger. In strong wind a serious mistake on the running backstays could still break your mast!

The running backstays control your forestay tension, and your check stays limit the amount the mast bends, and prevents it from "pumping" through waves.


----------

