I would like to raise the point where the boom fixes to the mast so that it will clear the spray hood as it currently is too low and fouls the hood.
As you can see from the pictures the main can be hoisted further up the mast and I think by doing this and re fixing the boom about 9-12" further up the mast it should clear the hood.
The boom is currently pop riveted to the mast so it would be necessary to drill out the heads and refix. The rivets have a 10mm head and look as if they are stainless. see picture.
Any advice on this mod would be appreciated.
John
ASHANTI 2008M
Hi John. I recently renewed the rivets on my boom fixing. If they are quite loose you can squeeze a metal saw blade behind and cut the river. If not then you'll have to drill them out. The debris drops into the mast. The rivets will be alloy. Ensure they are long enough for the job. Carefully drill holes after marking the points. I found using the river gun REALLY hard since my hands are not big.
All that said you need to be aware that this will raise the whole sail area and hence the amount of tipping for any given wind...so you might end up reefing down ....in which case you could just reef anyway which will raise the boom. If you do raise the boom ensure that you really test out how much raise is possible with the sail pulled up as tight as possible. ...otherwise you will never be able to get the luff fully tight which important in most wind conditions.
An alternative could be to put in a small reef point that you use in anything but very light or following winds ..When you wouldn't need the spray hood anyway....I have one and it's a useful tuning adjustment. My spray hood however does not foul the boom ......made by Advanced Covers in Southampton. ...to my own specifications.
Roly
Such a modification will have a variety of effects on the aerodynamics of the rig.
As Roly points out a higher main will increase the healing moment, giving increased bending load on the mast and increased loads on the shrouds.
Raising the gooseneck will affect the jib to main slot so the jib won't feed air to the main quite so well.
The alternative of reefing and lifting the clew will have a very significant effect on sail shape.
It's hard to predict if the effect on sailing will be insignificant or disastrous. One option might be to attach a second gooseneck and try the two positions out.
There isn't that much spare height as the fleet angle of the halyard into its turning block will increase making it harder to get tension on the luff.
The main may also foul the backstay.
Aluminium rivets will be too weak for gooseneck loads. I think Monel pop rivets are your best bet.
Don't use stainless rivets on aluminium, galvanic corrosion may concentrate at the small area of contact and erode the aluminium of the mast away from the rivet, hence loose rivets.
If you can borrow one, Lazy rivet guns (the concertina type) make quick work of hard rivets.
Dave Newton Sailbadthesinner
Thanks Roly & Dave,
The Spray hood came with the boat and looks as if its never been used - probably because it fouls the boom !
I will leave this job until the close season, and may well take Dave's advice fitting a second goose neck. That will save drilling out the existing ones which look like a hard material which is why I thought they were stainless.
Anyway I'll post the results when its done.
On a different issue can anyone identify what the item in the photos is ? I found it in the engine well - the thing is it looks familiar to me but I cant recall where its from.
As you can see its about 90mm long made from about 0.5mm metal with the plastic button "PUSH" - its obviously a release catch for something but what ? The engine and everything else on the boat sees to be working fine so it a mystery.
A couple of pints for the solution.
Thanks & regards,
John
ASHANTI 2008M
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