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Can I use kevlar or carbon tow to attach the gooseneck/vang

Posted: 15 Aug 2014, 18:07
by James Chrismas
Hi,

The class rules are clear in so far as the materials used to make fittings are unrestricted. I would like to be able to attach my gooseneck/vang fitting to the mast with Kevlar tow. I have recently learnt that I cannot do this as it is against the class rules.

So far as I can see there is nothing to prevent me doing so so long as the tow does not form part of the mast - i.e. the kevlar "ring" can be slid along the tube and fixed in position with a screw and/or glue. I would prefer to use a drop of glue as this would avoid the need to make holes in the mast that will be heavily exposed for corrosion - the reason I need to replace the mast. Would that be legal? - after all, I notice that the old vang was glued and screwed and the mast head and heal fittings on the old mast were glued.

Your early advise would be appreciated as I have just acquired the new mast section and want to have time to rig it before next Thursday's racing.

Thanks and regards,

James

Re: Can I use kevlar or carbon tow to attach the gooseneck/v

Posted: 16 Aug 2014, 00:12
by David L Alston
You should make a sketch of what you intend to do .. Your description is not really all that clear.... or take a picture of what you, by now, have done.

But = Fittings are not restricted with respect to their Materials of construction and MAY comprise a multitude of differing Materials .

I dislike the phrase/ term ' Legal ' intensely

Rather ' Compliant with the Class Rules '

The Gooseneck Fitting - MAY wrap around the Mast. Screws are fixings and are part of the Fitting

Always good to read the Class Rules ...bad idea to discuss thing like this at the pond

Where is Swear Deep Sailors it does not appear to be MYA affiliated


Dave

Re: Can I use kevlar or carbon tow to attach the gooseneck/v

Posted: 16 Aug 2014, 10:16
by James Chrismas
Dear David,

I am sorry that I caused offence.
David L Alston wrote:I dislike the phrase/ term ' Legal ' intensely
Rather ' Compliant with the Class Rules '
I shall try to remember use "prohibited" and "permitted" in future in line with the Sub-Committee: IOM ICA VC Technical's choice of words.
David L Alston wrote:Always good to read the Class Rules ...bad idea to discuss thing like this at the pond
I have read the Class Rules and was happy that fittings are unrestricted:
  • D.2.3 FITTINGS
    Fittings are unrestricted except that:
    (a) Fittings that can contribute to the stiffness and/or strength and/or watertight integrity
    of the hull shall be of materials permitted by D.2.1.
    (b) Ball and/or roller bearings may only be used for: sheet control line blocks, mainsail
    boom sheet blocks and headsail boom sheet blocks.
    (c) Fittings shall not project outboard of the hull shell or deck.
"
However, no mention of
David L Alston wrote: fixings
.
As our group includes at least one "commercial builder" and some other people who's authority I do not doubt (you may like to cast your eye down the latest results sheet - http://iomsailing.co.uk/14th%20August.htm I feel that a quiet word at the pond is useful. If in doubt I then ask for clarification.
David L Alston wrote:You should make a sketch of what you intend to do .. Your description is not really all that clear.... or take a picture of what you, by now, have done.
I have NOT "done" anything as yet. I was taught to assume nothing - hence my question. Last time I had a doubt about the interpretation of the rules I went through a similar process: viewtopic.php?f=7&t=1535

Re: Can I use kevlar or carbon tow to attach the gooseneck/v

Posted: 16 Aug 2014, 11:15
by James Chrismas
Further to the above, which I posted unfinished by mistake.


The photograph shows the situation as it currently stands and the problem I am trying to avoid. I can't attach a drawing as I do not have a scanner.
What I would like to do is:
Lash the fitting onto my new mast section using Kevlar tow and a drop of resin. This option is dependant on whether this is a permitted method of "fixing".
A harder and slower method would be:
Use an off cut of the old mast as a mould, coat with mould release agent, and lash the fitting onto the mould using Kevlar tow and a drop of resin; slide the fitting off the mould and onto the new mast section; fix in place with glue - very similar to my first option and preferable to screwing it in place, which wouldn't actually solve anything.

I hope this clarifies my questions.

I look forward to your reply.

Thanks and regards,

James
James I Chrismas
MYA No. 2973

Re: Can I use kevlar or carbon tow to attach the gooseneck/v

Posted: 17 Aug 2014, 09:51
by David L Alston
I do not quite understand WHICH problem you are trying to avoid.

1/ The terribly bad workmanship clearly evident - This I am afraid is well beyond the scope of the Class Rules.

2/ The corrosion cause by Stainless Steel in contact with the Aluminium

3/ ???


There are a hundred way to recover the mast if you really want to ... but in an earlier post you said you had got a new mast.

Here are the degrees of freedom you do have.

You MAY
1/ Tie the gooseneck to the mast with whatever material you like and resin it

2/ Push piece of plastic or aluminium tube up the mast so the screws bit into the plastic

B&Q sell a section of tube that will go up a 11.2 mast with a bit of sanding or slotting

MAY almost do anything you like BELOW the BOTTOM Mast Band - 1600mm

3/ Extend the 12.5mm section up to the Bottom Mast Band

4/ Offset the bottom of the gooseneck by about 0.7mm - you may find this useful.

5/ Only fix the gooseneck with two machine screws on the centre

I hate self-tapping screws




I am not sure why you attached a Race Result !! I will confess I did not recognise a single name but was impressed by the numbers - All I asked is - where you are sailing since it seemed the club was not MYA affiliated and I had never heard of it.

Re: Can I use kevlar or carbon tow to attach the gooseneck/v

Posted: 17 Aug 2014, 13:22
by James Chrismas
Dear David,

Thank you very much for your most helpful response.

1/ The "terribly bad workmanship" is down to the previous owner(s). I am not trying to recover this situation.

2/ "The corrosion cause by Stainless Steel in contact with the Aluminium." - Yes. I am trying to avoid as many potential causes for corrosion as I can.

3/ My biggest worry is based on past experience:
  • I had a big boat owner, who wanted to avoid all unnecessary holes in his new wooden mast as these are a major cause of water damage. After research and various discussions, it was decided to design fittings that could be bonded to the mast with glass fibre. On the eve of the Class's National Championships we went down to the boat only to find a notice fixed to the mast stating that we would not be able to compete as the mast was out of class! It was acceptable to glue and screw the fittings to the mast but not to glass fibre them to the mast as this would make them part of the mast. One very unhappy owner considerably out of pocket.
    Needless to say I don't wish to fall into this trap again.
I want to use your option - "1/ Tie the gooseneck to the mast with whatever material you like and resin it" - but I want to be sure that I am not falling into the trap I described above.

Do you think it would be sensible to apply for a formal ruling on the matter?


Thanks again for your help.

Best regards,

James


PS.
  • Our group are all members of affiliated clubs but there are several different ones. The location is a convenient central meeting point and, rather than form yet another club, we act as a group of like minded sailors. We have an arrangement with Emswoth SC and Emsworth Slipper SC, both of which have members in our group, to use their pontoons. The name I thought you might recognise was Rod Carr https://www.uksport.gov.uk/pages/rod-carr-cbe/.

Re: Can I use kevlar or carbon tow to attach the gooseneck/v

Posted: 17 Aug 2014, 13:52
by David L Alston
No traps there. But I doubt if it will relies because the resin will shrink very tight and release agent will not help at all in this area.

The best , for me is two machine screws on the centre and to Tap the fitting to M2. This allows me to pack the bottom out afterwards.. There is not a lost of stress on the fitting or the attachment at this point.

Ok -- have fun..

Apply for a rule interpretation ... what ever for ??

You have read the rules, you even repeated them on you post, you can read English. - are you next year's world champion.

Remember the key point --Below the Boom Band

Ok must go, got a plane to catch

Re: Can I use kevlar or carbon tow to attach the gooseneck/v

Posted: 17 Aug 2014, 15:20
by James Chrismas
Dear David,

Thank you for all your help. It is much appreciated.

"Fun" is the name of the game... and for me, my weekly outing when health permits.

"what ever for ??" belt and braces after costly incident I described in my last post.

"are you next year's world champion." I dream of it.

Have a good trip and enjoy your sailing too.

All the best,

James

Re: Can I use kevlar or carbon tow to attach the gooseneck/v

Posted: 17 Aug 2014, 19:58
by James Chrismas
David,

Further to my last post.

Your 3rd suggestion: "Extend the 12.5mm section up to the Bottom Mast Band" is the clear favourite for me.
  • F.2.4 CONSTRUCTION
    (a) Fittings and/or control lines may be combined provided their function is not extended beyond what is permitted.
I can combine the heel fitting with the gooseneck/vang fitting - problem solved.

Thanks again,

James

Re: Can I use kevlar or carbon tow to attach the gooseneck/v

Posted: 23 Aug 2014, 00:24
by David L Alston
Well you seem to be getting into the idea of it.

The 12.5 mm section is added to the mast and is not in reality a Fitting ... it is the Masts

So have a peep at the IOM Class requirements regarding the mast. As I said in an earlier post the bit of interest to you is the Mast below the Bottom Band.

F.3 MAST
F.3.1 MATERIALS
(a) The spar shall be aluminium alloy ................ or wood.
(b) Other permitted materials in the spar are: ...............adhesive...


Thus far the rule writer has only defined the materials in general


F.3.2 CONSTRUCTION
(a) A mast stub arrangement is permitted and, if used, SHALL be taken to be part of the MAST.



The bit below is very important because it defines the shape of the mast section


(b) Between the lower point and the upper point the spar section shall be:
(1) of circular outer shape,
(2) constant section .....



So you see it is not complex at all, you just got to read it without interruption. The IOM Class Rules are specifically structured in this way in order to keep it simply.

Most IOM rig builders take advantage of this because the Mast Step in the Hull is usually designed for a 1/2" mast and a 11.2 mast section slops about quite annoyingly.


In your case you have flat top hull i.e. the mast steps Onto the deck...not Into the Deck. This has some distinct disadvantages which is why the practice essentially died out 20 year ago.



Ooops ... 250 miles out.. lets get moving here. I must pack a bag, throw a boat into the car and get down to London for the IOM Nats.

So get it done and get sailing ... You evade the question as to where you sail ??? what is so &$%^&^& secret. Pop down to London and look at some of the best equipped boats in the world.

Re: Can I use kevlar or carbon tow to attach the gooseneck/v

Posted: 25 Aug 2014, 11:32
by James Chrismas
Hi David,

Many thanks for your continuing help.
I was able to sail last week with a temporary arrangement held together with cable ties and a spot of glue, which worked fine. Unfortunately my temporary arrangement for the spreaders was a bit too temporary but the wind was relatively light so I could continue - not very pretty but...
My boat was registered to David Roberts and, I believe, built by David Creed - it has a moulded deck with the mast step 80mm below the "..deck limit mark.." so fortunately doesn't slop about.
IMGP1012a.jpg
IMGP1012a.jpg (161.11 KiB) Viewed 18372 times
I wish you every success at the Championship - I see you are 35th after 4 races. A couple of our regulars are competing 'though not doing so well to date - Tom Lance 15, and Mike Brown 118 - and several are watching part or all of the event. I am registered through Emsworth Slipper SC. We sail from Emsworth SC's car park and pontoon every Thursday - some early arrivals can be seen warming up in this Google Maps link https://www.google.com/maps/place/52+Ba ... 853fe88c24 and from Emsworth Slipper SC's club house/pontoons on Tuesday evenings in the summer and Sunday mornings in the winter https://www.google.com/maps/place/52+Ba ... 853fe88c24
Unfortunately my health problems mean I am frequently unable to complete a whole morning's racing and almost certainly won't last a whole day so, much as I would love to compete in/visit the Nationals, it is not on. C'est la vie...

Thanks again for all your help.

All the best,
James