Converting a fractional rig to masthead (should I or Shouldn't I)

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EMAFC10

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I'm hoping to get some opinions on a decision I need to make.

I'm replacing the mast on a fractionally rigged Beneteau First Class 10 due to corrosion. She's a 1985 racer/cruiser and has a pretty bendy mast. Current rig involves runners and check stays. If I convert the rig to masthead (well, looking to go 19/20), I can do away with the runners and will only need the checks in a real blow.

She's a real pleasure to sail and is really well balanced, especially on the beat in a breeze. So I suppose the first question is do you think I run the risk of compromising her general handling characteristics? I say general because I fully appreciate that I'd be sacrificing tunability, which brings me onto my next question.

Is there then a chance that I'm sacrificing the future value of the boat? Being a pretty competent club racer (the boat, not me), are future buyers going to be looking for that tunability? We aren't die hard racers so we don't make use of everything she has to offer in this regard....but I don't want to ruin the future value of the boat.

The last thing to consider (at this point) is that we haven't the money for new sails so we'd be using the old headsails. The deck to forestay angle will increase by circa 2-3 degrees. A boat pitches 2 to 3 degrees constantly so I can't imagine this will have a noticeable and detrimental effect on the head sail performance but wanted to see what people with more experienced thought. The forestay will increase in length substantially (circa 1.4 m) and it'll look a little silly running with a short headsail but it's probably not the only thing making me look a little silly.

I'd love to hear what people think because I'm really torn on the issue.

Many thanks for the advice.
 
EMAFC10 said:
I'm hoping to get some opinions on a decision I need to make.

I'm replacing the mast on a fractionally rigged Beneteau First Class 10 due to corrosion. She's a 1985 racer/cruiser and has a pretty bendy mast. Current rig involves runners and check stays. If I convert the rig to masthead (well, looking to go 19/20), I can do away with the runners and will only need the checks in a real blow.

She's a real pleasure to sail and is really well balanced, especially on the beat in a breeze. So I suppose the first question is do you think I run the risk of compromising her general handling characteristics? I say general because I fully appreciate that I'd be sacrificing tunability, which brings me onto my next question.

Is there then a chance that I'm sacrificing the future value of the boat? Being a pretty competent club racer (the boat, not me), are future buyers going to be looking for that tunability? We aren't die hard racers so we don't make use of everything she has to offer in this regard....but I don't want to ruin the future value of the boat.

The last thing to consider (at this point) is that we haven't the money for new sails so we'd be using the old headsails. The deck to forestay angle will increase by circa 2-3 degrees. A boat pitches 2 to 3 degrees constantly so I can't imagine this will have a noticeable and detrimental effect on the head sail performance but wanted to see what people with more experienced thought. The forestay will increase in length substantially (circa 1.4 m) and it'll look a little silly running with a short headsail but it's probably not the only thing making me look a little silly.

I'd love to hear what people think because I'm really torn on the issue.

Many thanks for the advice.
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Doubt I can add much to your own analysis but would give primacy to the original design and the obvious satisfaction you've derived from predictable performance to date. If you're not going to buy a new larger headsail, you'll not benefit in light airs. The unused stay length from using old sails is not significant in the mix I think. Fractional rig is a pretty good setup - I've sailed this style for 30 years. I guess there'll be new stays with a new mast?

So balance of downside to upsides of changing - 60:40 or even more?

PWG
 
I think one desirable feature of a typical fractional rig is the absence of an inner forestay so making tacking the jib much easier. Another advantage is the generally smaller jib and larger mainsail. I would strongly suggest staying with a fractional rig. However as you know running back stay and check stays can be a pain to set up on each tack.
A less bendy mast ie greater dimension fore and aft an help. As do swept back spreaders and aft mounted chain plates. Possibly more spreaders. The intermediate side stays pulling back against aft swept spreaders can give stiffness to a bendy mast. (the further aft the chain plates the greater mid mast support but of course the greater problem of main sail chafe on stays
Another option to avert running back stays on a very fractional rig is to fit diamond spreaders at the top of the forestay facing forward extending to top of mast and down to about mid mast. These will transfer the top back stay pressure to the top of the forestay.
Unfortunately every thing in this rig design is a variable so while arrangements are simple and logical it is difficult to decide just how much mast support is enough. ie you have a system with runners which has proven adequate. Do away with runners on the same mast and you must get stiffness with spreader arrangement etc. Is that enough? You might consult an expert in rig design to give you confidence .
No don't go the mast head rig option. Ok move the forestay up the mast won't make much difference but a bigger jib samaller main will necessitate moving the mast aft and that would be too much. It is that mast support fore and aft in the middle and at the top of the forestay that matters.
Incidentally why are you replacing the mast? ol'will
 
A lot of variables!
Are the spreaders currently straight?
Changing to a rig with no runners might really need the spreaders angled back.
That might imply moving the chainplates...
If the current mast is 'bendy', then changing to a stiffer section might be an option, reducing the need for runners and checks.
A stiffer mast will possibly make your mainsail obsolete?
Is it keel stepped?
IS there much potential for altering the rake?
 
Other things being possible, I would try for 19/20. A major benefit is reducing the crew expertise required whether racing or cruising; you also presumably free up a cockpit winch, and you get a rig that doesn't need much/any farting around with on a routine basis (it does need significant attention to set it up right from the get-go).

Also on resale. In my opinion, as a keen racer who shies away from buying a yacht for racing purposes, one of the really off-putting things is the need to find good crew. It's easy to find people who want to be taken sailing on a nice day; harder to find people who want to commit, regularly, and whatever the weather...and can contribute. I'd consider it "resale positive" to simplify the boat. I've raced on bigger boats with your type of rig, and finding crew has always been a massive headache.

But subject to various things already said:
- balance. I would have thought this is surmountable. If you went for a slightly taller headsail with the same foot I shouldn't think it'll move the CofE much; in any case there's much more to boat balance than the fore/aft position of CofE; if you sail with 1 degree less heel you'd probably cancel it out. You can perhaps add a full-battened mainsail with a bit more roach. (I'd be looking to do that anyway, but appreciate it's extra £££). If the mast is deck-stepped you can also play with the rake a bit; ensure your new standing rigging has a decent range of adjustment
- headsail. if you raise the forestay a little and use the same headsail, you may lose the benefit of "end-plating" at the foot; that may or may not bother you from a racing perspective.

for me the showstopper may be the chainplates. A 19/20 rig does need aft-swept shrouds and spreaders. One for you to measure up, perhaps compare with neighbouring yachts of a more modern vintage, and consult the mast manufacturer.
 
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Further to the comments already made, I would suggest seeing if there is a First Class 10 association and ask for advice there as corrosion must have affected other masts already.

Using a thicker mast will also add weight aloft and would raise the centre of effort, so you would need to be more careful about reefing slightly earlier.

Runners can be a pain, especially if short handed. It would be wise to talk with a mast manufacturer like Z Spars to see what they suggest. They may have a solution that could allow no runners.

Also if you change the rig to masthead your boat will no longer remain as originally designed and could cause you massive problems with insurance companies. They may require new data from a designer to conform to the Recreational Craft Directive - even if we no longer have to comply with it.

Personally I would stay with the fractional rig. I have a true ¾ rig and love the controlability of the mainsail and smaller headsail.
 
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I think I would keep the rig fractional and pretty original. Do away with the runners if you want but keep them for the next owner should they want them.
Your typical buyer is likely to be keener on speed or racing rather then accommodation and cruising, so it probably makes sense to cater for this mythical buyer.

It may be possible for the riggers to suggest a stiffer mast section that would give you less effective tweaking but a greater margin offshore, shorthanded. Also ( obviously but maybe with saying), the boat would be much less needy with very early reefing.

There is a French site you may not have seen, most of the links still seem to work:

First class 10

.
 
TernVI said:
A stiffer mast of bigger section need not be heavier.
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A year or two after I bought my boat they changed the mast section for later boats, both 19/20. My mast is quite bendy but the new mast was narrower in section but deeper and the ones I have seen are almost straight. Something like this could be a solution, though I would want the advice of rigging experts before deciding.
 
All very helpful, many thanks. Just so you appreciate that I'm not asking a bunch of strangers on the internet how to possibly rig a boat, I have quotes from Z Spars for a replacement in kind (but a beefy tapered section at the masthead) and a 19/20 rig. They just need to know which one I want to go for.

Answering some questions:

The spreaders are swept back. According to Z Spars, I could do away with the runners and checks if I reposition the chain plates such that they sweep further back but the cost to do this is prohibitive.

They haven't offered a solution that involves a different mast profile (i.e. sturdier). They know what I'm looking for so I'm assuming the option isn't there. I'll ask to make sure on the basis they said nothing could be done unless I moved the chain plates...it was me who suggested the 19/20 rig as opposed to them, and that turned out to be possible.

Thanks again for the input.
 
EMAFC10 said:
The last thing to consider (at this point) is that we haven't the money for new sails so we'd be using the old headsails. The deck to forestay angle will increase by circa 2-3 degrees. A boat pitches 2 to 3 degrees constantly so I can't imagine this will have a noticeable and detrimental effect on the head sail performance but wanted to see what people with more experienced thought. The forestay will increase in length substantially (circa 1.4 m) and it'll look a little silly running with a short headsail but it's probably not the only thing making me look a little silly.
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Don't forget that the change of headstay angle will raise the clew significantly which will mean you need to sheet further aft. In fact the sheeting geometry will change considerably so will be worth thinking seriously about. Moving genoa tracks will probably not be cheaper than a new genoa.
 
Thanks for this, a very good point. I had considered this and is why I mentioned the angle between the deck and forestay only changed circa 2 to 3 degrees. With the foot of my headsail being 5.5m, a 2 degree change will lift the clew circa 19.2 cm. It was something to consider but I didn't think it was significant.
 
The sheeting position will need to move aft by a good bit more than the clew has moved up, in order to maintain the same angle to the forestay.
 
Yes, to do properly its a lot more work than simply the new mast.
Without increasing the rake angle of your spreaders you will end up with a rig likely worse than the existing one.

Even with a 19/20 rig, most of the work of opposing the forestay is done by the cap shrouds and the forestay is primarily still used to flatten the main, although it also increases forestay tension more than your original would. I did a similar conversion last year & it involved moving the chainplates, not a job for the faint hearted.
 
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