Mast Step Compression

[wooslehunter]

Hi All,

I recently looked at a Colvic Sailor 26. The mast step looked a little concave rather than flat as if the rig was trying to push itself through the deck. I've heard of this problem before on other boats but cracks in the step are the normal give-away. There were no cracks or evidence of repairs in this case.

I'm a bit loathed on spending money on a survey to have it fail on something so obvious.

Does anyone have any experience of this problem, or is the mast step shape normal on this kind of boat?

Thanks, Dave.

 

[Chris_Stannard]

If the mast step is concave this could mean that the compression tube, the steel tube, that takes the force of the mast down to the keel is failing. If it is made of mild steel, as they often are, the plate at the top rusts and the mast starts to sink giving that concave appearance. This is because the unwary owner does not realise what is going on and finding his shrouds a bit slack winds up some more.

The problem can also be caused by simply winding up the shrouds to tight, or by applying too much backstay pressure, thereby trying to drive the mast through the boat. The boat can go banana shaped, which will be indicated by doors not fitting or trouble with the washboards

My first step would be to have a good look at the compression tube, it will cost about £1000 to replace. If it is okay then I would be inclined to think there is a distortion problem. Do you know anyone who can look with you, one ploy might be to ask a rigger to give his opinion since they are ususally the ones who sort these problems out.

Chris Stannard

 

[30boat]

I had exactly the same problem with my Westerly Fulmar.It was so bad that the mast step was concave almost to the point of breaking.The mast is 12 meters tall but I worked up a way of lifting it clear of the deck and pulling it back enough to clear the area.It was terrifying to say the least.I then cut the area open so that I could reach the compression post and discovered that it was built too short forcing the deck to deform untill it met the post .I was appalled at such shoddy workmanship from Westerly,especially because the boat must have left the factory in that state.The top of the post was built up and then the deck was rebuilt with cloth and epoxy.It was all done without lowering the mast and it took no more than three days to do.No problems since.

 

[Lofty]

I had a problem with slack rigging on my Macwester 27. The surveyor I asked to advise me just laid a straight edge across the cabin top which revealed a drop of half and inch. A bit more presure on my rigging and I could have got that figure up to anything I wanted. A piece of string will do if you pull it tight.