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Boom Bend

Postby andrewb on Thu Jun 14, 2007 10:10 am

What are the class legal options for dealing with excessive boom bend? Can an insert be used to stiffen the boom?
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Postby swearly on Thu Jun 14, 2007 6:05 pm

Andrew
My understanding of the rules is that you are not allowed to do anything. If your bend is excessive it is probably because you are using a light section. A simple solution - buy a heavier section and change your fittings over. Personally I think this a good rule as it encourages you to use a heavier section which is less likely to break.
Stephen Eary
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Postby andrewb on Fri Jun 15, 2007 10:22 am

As far as a I can see from the rules so long as the OD is between 50 & 55 mm you can do anything you like. From this I assume that an insert could be placed within the tube, or an external sleeve used. If there is something more in the 'hidden' rules (i.e. building notes) this needs to be made public as not all 2nd hand boats come with the building notes!

Andrew.
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Boom rules

Postby GuestMember on Sat Jun 16, 2007 7:37 pm

Hi Andrew

The rules expressly outlaw stiffening in the mast.....they don't mention any restriction on the boom. Then again the rules also state if it doesn't say you can ...then you can't. I suspect you can't stiffen the boom.
In my experience excessive bending is caused by corrosion around fittings which weakens the boom.
The thin section booms, with correspondingly higher tempers to give enough strength, are susceptible to failing if corrosion sets in.
To minimise corrosion use corrosion reducing paste between stainless and alloy (Duralac) or similar.
Washing well with fresh water will also help.

Cheers
matt
1697
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SLEEVES

Postby peter reid on Mon Jun 18, 2007 12:03 pm

-The famous Cameron Hooper- protest at the Kingston Nationals (Tasmania) where 2nd place was disqualifed for a mastsleeve put a very clear precedent on sleeves - they are not allowed full stop
The unfotunate fact of that Nationals was that it was extremely light and the sleve would have hurt more than it helped -Cameron was an excellent sailor who earned 2nd by sailing brilliantly-
That Nationals was the most political Nationals ever with 3 Sabre Association Officebeares being flown for free from Melbourne to Hobart to sort out the mess- There was a bigger controversy as the eventual winner should have been disqualified for substituting and engraving another boats number into the sabre he was sailing ( a real sabre style fine cotton affair)- so there were two sabres with the same number - the phantom one though not measured was belived to be faster- after measuring the boat did comply with measurement rules and the winner was not diqualified-but it was no doubt a fraud and i always believed that the attempted deception should have resulted in disqualificaion- when it was quite clear that he did the false engraving into the hull floor
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Boom Sleeves

Postby Mike Simpson on Mon Jun 18, 2007 2:38 pm

This is the relevant Measurement Rule:
7.1 a. The boom shall be made from constant section round aluminium alloy 50mm diameter x 1.5, 2 or 3mm gauge.

I think the term "constant section round aluminium alloy" precludes the use of stuffers, sleeves or whatever.

Mike Simpson
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Re: Boom Sleeves

Postby andrewb on Tue Jun 19, 2007 10:22 am

Mike Simpson wrote:This is the relevant Measurement Rule:
7.1 a. The boom shall be made from constant section round aluminium alloy 50mm diameter x 1.5, 2 or 3mm gauge.

I think the term "constant section round aluminium alloy" precludes the use of stuffers, sleeves or whatever.

Mike Simpson


Which set of rules is that Mike? The only ones I have seen don't have a section 7.1a (see http://www.sabre.org.au/documents/Sabremeasurements.pdf or http://www.sabre.org.au/MastBoomMeasurements.html). If this is in the printed rules or building notes this is an excellent example of why the rules need to be consolidated into one publically available document. According to the rules published on the site there is no restriction on the section of the boom & any protest resulting from using these published rules would be interesting to say the least.

I have followed the arguments surrounding the rules / building notes, but in all honesty the Class has far more to loose than gain by not making the definitive rules publically available. Having an incomplete or misleading set on the website is probably even worse. I would suggest as a matter of urgency that the set on the website be reviewed & either removed until the definitive set is posted, or a clear notice posted on them that they are incomplete.

Andrew.
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Postby GuestMember on Wed Jun 20, 2007 2:37 pm

Gee Andrew, your seem really fired up about measurment rules and any possible holes you can find.

Is there a reason why you wouldn't just replace the boom given it costs around $60 to get a new one.

If the boom is bending its probably at the end of its life anyway, and failure of a critical part like that out at sea could result in an injury or similar disaster to the sailor.

I'm not sure why you'd want to make a simple (and cheap) boat complicated.

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Postby andrewb on Thu Jun 21, 2007 10:41 am

I'm not looking for holes - just pointing out the obvious from the point of view of someone new to dealing with sabres. To put it in perspective it is my wife, not I, who sails the sabre. I did the searching around looking for boats & help with maintanance / repairs when needed. Having sailed a number of clasees the Sabre came as a bit of a surprise as to the rules. There are what seem a perfectly good set of rules posted on the website - as for most other clasees (I have mainly sailed ISAF classes so the full rules for them are available on the ISAF site), but as I have discovered there are 'other' sets of rules around - primarily the building notes & now it would appear - 'different' sets of rules that different people work to.

What surprised me with Mike's response is that there is obviously another set of rules somewhere with different wording. Replacing the boom may not be much in monetary value, but according to the rules on the website there is nothing wrong with sleeving the boom. What Mike put on the board suggests that if you competed with such a boom you could be disqualified under a set of rules of which you had no knowledge. There is nothing on the website measurements to say that they should not be taken as the definitive set of measurements for the boat. If the 'Cameron Hooper' case were held today over a sleeved boom I don't think the boat could be disqualified.

Talking about a simple boat - it uses that towel rail which I was (luckily) able to get welded up as I work with people who can so ss welding readily. Otherwise I'd have had to purchase a new one ($60?) rather than use about 50cents worth of webbing for a better all round result. Not every 'new' thing is more complicated or more expensive.

Andrew.
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Postby Mike Simpson on Tue Jun 26, 2007 11:55 am

Association members are always welcome to call their local measurer and/or National Measurer Phil Johnson (Refer "Contacts" on National page or relevant state page) with construction or measurement queries.

An important clarification - the measurements shown on the web site do not include the Rules (Appendix A to the Constitution of the SSAA) which are included in the Construction & Fitting Out Notes.

It should also be recognized that the Notes are specified as being part of the Rules and departures from them can result in an illegal boat.

Members can purchase a current set of notes from me for $33 inc postage. (Non members $63 including one year's membership of their state association)

The Notes are presently under review by the State Branches and Measurers, but I do not expect there will be major departures from the current set.
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Confused

Postby Slow Hand on Tue Jun 26, 2007 11:00 pm

So now I am TOTALLY confused!

Not that I want to sleeve my boom.... BUT....

.... does this mean every member has to purchase a set of construction notes if they want to ensure they are across ALL measurement aspects of the class?

Like hey man, I didn't build my boats.
And even if I did I couldn't be sure the notes haven't changed!!
And what about me mate who bought a $500 boat, he cannot afford another $33 and besides he doesn't have access to this forum to know this stuff.

This is a real problem, and a National one at that.
The solutions are totally out of touch with a National class with sailor dudes thousands of kms apart. Those in small numbers at a distance need this matter resolved satisfactorily, quickly, else they will lose interest, do their own thing and by default stray from the class.

Nui Uma
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Postby Sabre on Sat Jun 30, 2007 10:59 am

The complete set of rules and measurements has been posted on the site as of this morning.

If people require a clarification in regards to any of the rules noted in the document, I suggest they contact directly there state or national measurer via the contact details on this website to discuss further.

On a personal note (note representing the association), regarding the towel rail debate, Binks sells then for $30, John Dixon (Vic State Measurer) has them for I think $50-$60, which includes a one piece beautifully designed slider and attachment mechanism which I use personally and happily recommend.

Or you can make one yourself. This has been discussed a number of times.

Yes there are a number of other unapproved options including a track in the boom, wire loops, Velcro etc used across a number of classes etc.

However I have also been present at a number of debates with some of the top Sabre sailors who have discussed the outhaul fitting at length (normally over a beer after a race). Without doubt the majority 95% + have come out in favour of the current towel rail as the superior fitting.

Note the majority have been sailing for 30 to 50 years and have tried all of the solutions noted above across a wide number of classes.

The above is to put in perspective some of the debate taking place, and hopefully to allow it to settle a little (at least for a while).

Regards

Ashley Parkinson
VIC Sabre Committee
Last edited by Sabre on Tue Jul 03, 2007 3:36 pm, edited 1 time in total.
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Outhaul Fittings

Postby Phillip Johnson on Mon Jul 02, 2007 5:38 pm

The only fittings permitted on the end of the boom to allow the clew position to be adjusted is the towel rail fitting shown in the building notes.
The recent changes to the measurement rules do not in my opinion change this. I believe that if this change was to occur a specific notice of motion to change the rules would be required and the states would have to vote and decide. This has not happened so I will not issue a certificate or approve the installation of other fittings in place of the towel rail at the present time.

Phillip Johnson
National Measurer
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