TOPIC:

could anybody give me some advice on prebending the mast by fitting some form of cascade under the deck to pull the mast forward in light conditions to flatted the main.My hull is a woof and the heel of the mast is built up from the floor so I think I need to pull it from above deck level but not sure how high and if deck support would need strengthening or whether conventional deck fitted mast rams can be used to induce bend as well as stiffen the mast.



many thanks john

Hi John,



There are numerous ways of prebending your mast but here are some of your options depending on how much work, money & effort you want to put in.



1) Use a cascade or block & tackle system from the bow just underneath the deck to the mast just under the mast ram. This can only be done if you do not have a full size bow tank. If you have a wooden woof and not a woof derivative then I suspect this is the case. This is the easiest way to do it, but may not be the most effective.



2) On one of my boats I have a support going from the back of the mast foot upto the underside of the deck. I have managed to add a cascade that goes between the mast and the support with a cascade that pulls the mast back & then pull the load down. This seems to work quite well, but i did it as it was the most straight foward thing todo with that boat.



3) Another alternative is to have a 2:1 strop above deck which then pulls down with a cascade system. I have seen this on a Young woof & it looks to work well. This works inconjunction with a normal mast ram. It may however require some reinforcement of your deck.



4) Add a mast ram/ prebend strutt. I have just bought one and i am about to fit it at some point. I suspect i may have to add a support between the back of the mast step and the under side of the deck to counter act the forces. I believe the theretical best place to put the strut is in line with gooseneck. In practice this will is not pratical and you will get your jib sheets in a mess everytime you tack! I suspect the middle of the strutt will be 10 to 12" above the deck, but i have not been round the dinghy park with my tape measure yet, so maybe somebody else can help if you decide to go down this line!



5) Use wooden chocks!



I hope this helps



Phil

John

I have fitted a Fireball type strut to my mast. To my surprise it doesn't catch the jib sheets at all even though it goes up to the gooseneck. If you buy one remember to stiffen up the foredeck with a post underneath - as the downward force is large if you fall off a wave! Good luck

Hi Phil,



Looking at the options I think I will try strut with support under deck to take the load.I wasn't sure that I could pull the mast with a strut as well as using it as a mast ram.Thanks very much for help



John

Hi Jeremy



As its only a short distance from the mast heel to deck fitting a strut higher sounds a really good idea.



Many Thanks

John

Hi All,



Does the top of the track on the mast equal the gooseneck position or is the centre of the track on the mast that is centred to the gooseneck position.



Also how far forward from the back of the mast gate on the sheerline does the fix point for the bar go?



Also have have some photo's of my Kingsfield with a support below the deck if any one wants these send me a message and i'll foward them on. This uses a piece of wood that shapes around the port hole in the tank and has two aluminium brackets.



Thanks



Phil MrGin2008-03-13 17:30:01