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Hi all

I removed the mast beam today, untying the lashings and noticed the top of the beams had been crushed slightly by the rope lashings. (rope indentations)

To avoid more wear and tear when afloat would it be a simple case of gluing some hardwood strips on top of the beams ?

Including those that are in the plans for the leading edge of the beams ?

Does anyone have a different solution ?

all the best

P.

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Hi Paul,

See Neil's recent posts on beams at http://thegledaproject.com/

He has just gone through this.

Thanks Roger.

I'd go with a thick laminated glass/epoxy bedding pad on the beams, in the areas below lashings. 

Jeremy i have considered this solution, the glass and epoxy sandwich would in my opinion not stand up to the crushing pressures applied by the lashings. I feel the epoxy would crack before a hardwood pad would.

cheers paul.

Paul - good to hear from you.

One idea I had but never had to use was to cut a short length of domestic water pipe [ copper ] lengthwise into quarters and to bed this on an epoxy bed on the corners of the beams where the lashings bear on the beams.
I might still get around to this. This should take care of the friction / crushing issue. The issue is mostly on the corners of the beams where the lashing bear.

I have had the issue of a lashing fail on an open sea passage due to a lashing cutting into the beam to meet a screw head which promptly sawed it apart.  On a related topic this is partly why I do not believe in a lashing tightening system which cannot be done afloat. Keep it simple. And go sailing.

 

That would have spoilt yer day Galway. i have fashioned some pads out of hard wood and will glue em up soon.

Hey Paul, I also was concerned for the soft timber and pressure grooves from the rope.
I ended up glueing a domed piece on top of the beam where the rope goes over for two reasons.
One is to protect the timber edges where the ropes bends to go over the top of the beam and second is to maintain a more constant pressure across the top of the beam.
Think of it like a cord being laid over a box vs a ball, which is basically what it is, the box gets pressure on the edges but in the middle where the cord is straight there is hardly any contact pressure but over the round shape contact pressure is more evenly applied across the span.
Don't know if the benefit is real or perceived but it made sense to me at the time.

When I refinished and glassed my forward beam, I used these Wharram-designed  lashing doohickeys to protect the beam edges and help located the lashings:

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Paul; sure, a sacrificial hardwood pad will do as a quick'n'easy solution. But the glass/epoxy composite i am talking about is definitely harder than just about any wood....lignum vitae is maybe as hard if you can get some.

Even so, areas for moisture trapping between the sacrificial pad and beam, indeed, between the lashing line as well, will be a problem. Best would be to glue the pad onto the beam, which means prepping the area and mixing epoxy anyway. So I would just go one step furher and create a nice thick and well radiused composite bed. This will prevent any decay under the lashings.

Jeremy, could you give me more detail as to how you would go about making the composite.

I am guessing a mixture of microfibres and epoxy with glass sandwiched in between?

cheers paul.

I have used large diameter clear plastic hose cut in half and sections placed around the beam edges under the lashings.  Degrades a bit in the sun where it is not covered by the lashing is the only downside I have spotted so far.

Hey Paul, my bad, I see from Kim's photo I was referencing a different design beam construction, we have Wharram's H beam with a large flat area across the top so my description would have made no sense at all, sorry bout that.
Shaun

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