Cradle pads?

Clyde_Wanderer

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What do the board recommend for covering the 18mm ply on my 6 cradle pads?
I had rubber on the old pads but this has broken up and degraded, now its time to make new pads and recover, but with what?
TIA.
C_W
 
I've always just used 8" square scaffold plank off cuts with nothing as the wood is kind to the hull. Soft stuff allows grit and the like into it and gets manky.

So for me it's bare soft wood.
 
Not carpet

Definatly NOT anything that holds moisture that is sponge like carpet/open cell foam etc, If you leave it for too long it can cause osmosis in the spots on the hull
 
Definatly NOT anything that holds moisture that is sponge like carpet/open cell foam etc, If you leave it for too long it can cause osmosis in the spots on the hull

Can you give a citation (evidence) for this please ? I have never seen square patches of osmosis.
 
Lidl and Aldi often have cheap mats for kitchens or workshops (woven polypropylene). They do not hold water and can be easily cut to shape.


One alternative is to make friends with your local tool hire shop, and buy some old floor cleaning pads . These pads have to be renewed every time a machine goes out, and are available for a couple of squid a time. From 1 to 2 cm thick, they are strong enough to retain open volume under pressure, so dry easily and quickly.
 
Can you give a citation (evidence) for this please ? I have never seen square patches of osmosis.

I have.
On dinghies, where the gel coat is thin and they sit on the same soggy carpet all year.

rubber is good, preferably ribbed.
Astroturf is an alternative. Probably too soft for yacht use.
A layer of closed cell foam under the rubber is good.
 
What do the board recommend for covering the 18mm ply on my 6 cradle pads?
I had rubber on the old pads but this has broken up and degraded, now its time to make new pads and recover, but with what?
TIA.
C_W

had some success using the hardish foam knee pads you can bu8t from garden centres / diy stores. Contact adhesive.

They are closed cell an with my 8 tonne boat on four pads they did not squash flat.

Mine looked likethis without the graphics and I think a bit cheaper.
 
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Can you give a citation (evidence) for this please ? I have never seen square patches of osmosis.
Yes, common in dinghies that rest in padded hull shaped cradles. Have even seen it in new hulls kept on cradles. Strips of osmosis all round the hull.

Not sure it would be a problem on a cruiser where the pads bear on antifouled parts of the hull.
 
Tranona beat me too it, It is more common in dinghies and yachts kept on trailers "trailer sailors" But the yard my parents kept their boat in had warned a few of the "longer term" refits about it.
 
Osmosis and pads

Agree with Andyxs,
Been there, carpet pads covered with polythene did produce squarish areas of osmosis,none anywhere else on boat.
Also on more recent vessel the deck under the life raft was showing bubbles in gel, so was raised on slips of solid wood to reduce this effect.
That hire shop pad idea sounds good,as does minimising the area of the pad bearing (smaller pads).
 
Some time back I made up some steel beams for lifting a 1 1/4 tonner on and off it's trailer. For the contact pads I used off-cuts from thrown lorry tyre tread, which is often found on the side of major roads.
To hold them in place I found that c/s s/s through-bolts were required, as contact adhesive wouldn't hold.
 
I knew someone with a grp boat who fitted it out while on a cradle in the garden; that took him 18 months, and the boat was already a few years old.

The cradle pads were covered in carpet, so got soaked by the deadly fresh rainwater; by the time the boat was launched she had osmosis at all 4 pad positions.

As a precaution he applied Gelshield to the inside of the bilges as well, but I think that particular boat had a very thin gelcoat and the damage was done.

On the other hand, I've never heard of a boat being sunk by osmosis !

I do think Gelshield - or the Blakes equivalent - is a good idea though.
 
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On the other hand, I've never heard of a boat being sunk by osmosis !

Do you think you ever would? Can you imagine a yottie going to his insurance company and saying " it was osmosis that sunk my boat so obviously I cannot claim". As opposed to " I hit a rock and we sank". Particularly since hitting an osmosis weakened part of the hull is the likely event anyway.

On a Sadler 29 I've personally seen osmosis blisters with a soft much of degraded layup behind them. A poke with a small screwdriver showed that the soft mush was already more than halfway through the laminate, so I think that on some older / worse built boats, there will be soft spots penetrating right through the hull. In his book, Tony Staton Bevan showed a picture of just such an case where gentle pressure on a screwdriver put it through the laminate.
 
Seen two similar examples of boats that had been stripped for re gelcoating, only to discover the equivalent of wet cardboard underneath. One was a mates Centaur that needed the whole of the bottom of the hull between the keels cut out and a new section laid up. The other was an Elizabethen 29 where you could see through the hull and out the other side where the laminate had failed. That boat was scrapped.

So not sunk as such, but outward osmosis hiding major failure of the laminate. Bet there are lots of 70's boats like that around, just like ply boats with rotten or failed internal veneers.
 
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