Loose ballast and seaworthiness

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grumpydog

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Our boat should be sailing next year, and I was thinking about our loose iron ballast which will lurk under the sole. I asked our surveyor a year ago if this was safe (IE would it cause carnage smashing around the cabin and people's heads in the event of a knockdown) and he said that it was OK - a boat like Billy Blue (for that is her name) would never be knocked down! She's a fishing boat shape, broad and stout, 30ft and an unbelivable 10 tons in weight, so it certainly would take a lot to knock her down. But by my understanding, a breaking wave as high as her beam (about 9ft) hitting her broadside would actually cause a knockdown. I'm not planning to round Cape Horn - so am I being overly academic? Or am I being sensible? And if the latter, what is a good way to secure these potentially lethal blocks of iron under the sole? I was thinking some sort of system of straps might be the answer...
 
I have ballast, sandbags from Travis Perkins, tied up in a stouter woven bag. Often wonder why you chaps don't use it: not heavy enough? It's cheap and it doesn't move. Woven bags can soak up the muck a bit. Better is stainless steel punchings in bags, if you can find them.
 
I guess your surveyor would only comment on this within the scope of his survey and your defined area of use.
I would suggest that you affix substantial timber battens to stop athwartship and fore and aft movement as this would be the most likely direction your ballast would take and subject to the depth below your sole boards you could either just fasten down the boards if it is a very short distance, or again affix battens to the boat structure across the top of your ballast pigs. I would agree that unless you are going seriously offshore then leaving it alone is probably reasonable. If your surveyor was concerned about it he would have advised differently.
 
I think that this is one of those factors which you will unconsciously apply when considering a particular passage, just as you will consider the approaching weather, the fetch and the depth of water. At least you have the peace of mind of knowing that your ballast won't leave the ship without your permission, as has so often happened to Round-The-World sailors in most inconvenient locations. As you become more familiar with the ship, your confidence will grow, and it will become one less thing to be terrified about. There will still be plenty of others.
Peter.
 
I would definitely have the ballast, plus anything else as potentially dangerous secured, very odd advice from a "surveyor"!
Surprised, seeing the designer, there is no provision for the ballast to be secured!
 
Well thanks for the replies. I tend towards the opinion that it's just as easy to have it secured as to have it unsecured, so that's what I'll do. Interesting point about the sand. I can see many advantages: rust neutral, cheap, soaks up bilge water, and can squeeze into gaps. Very nifty.
 
It's delivered in waterproof bags, so won't soak up, but the bags tend to degrade, hence the tougher outer bag.

I was in a 1902 pilchard driver many years ago, when we lifted the fishroom boards to look at the ballast we found old, broken and mis-spelt gravestones. cast a bit of a pall on our optimism.
 
Depending on the particular circumstances and your layout of natural obstructions in the bilges, simply shifting a bit through rolling might be more likely than actual knockdown and having it crashing out through the cabin roof.

We once had a converted lifeboat with a very wide flat bottom, where we though perhaps there was a risk of the ballast shifting sideways. In that case we lashed it (ex railway fishplates) down through the gaps between the ribs and the clinker planking.

In my boat I have lots of old sashweights, ideally suited to rolling about. But they are constrained to the centreline by the structure of the bunks, and the sole boards are secured. I haven't the remotest wish to go anywhere that would put this to the test, but it seemed sensible and workmanlike.

I realise that in reality any form of fixing might be ludicrously insubstantial. A few brass turnbuckles aren't going to support your 10 tons of upsidedown ballast anyway.
 
Normally the cabin sole is secured when you have inside ballast - but make sure that you maintain and can get at the fastenings easily. I seem to remember that Frank Mulville had a big problem with this in "Terschelling Banks" when he had to find a leak.
 
Hi hadnt relaised it was a hillyard sailing yacht! Our 12 ton hillyard has ballst pigs in the bilge and it has never been commented on by any previous surveyor but our pigs are secured athwartships and fore and aft with battens and chocks. The sole boards are substantial Pine and screwed down, my previous boat had the same system which i fitted myself. You could theoretically suffer a knockdown and hence my questioning the distance between pigs and under side of sole boards.
 
It is usual to secure it somehow. Usually with battens/chocks/wedges/brackets. In practice it is hard to achieve. The idea is to wedge it so tight it can't begin to move. The other point is to keep it off the planking, and off the fastenings in the timbers/frames too. It took us quite a while to chip/clean/load our ballast, by which time we had had enough and it is unsecured, but well wedged in. (there are 3.6 tons of it)
One day, when I find enough church roofs, I will cast lovely T-shaped lead ingots that will be easier to secure. Untill then, I will stay out of the Southern Ocean!
 
In a similar vain, we have some unsecured trimming ballast which I have spent some time worrying about (the surveyor was worried to). It consists of a large pig of heavy metal sitting atop the keelson just behind the stem knee - another smaller piece rests across two timbers on the port side. Neither has moved a fraction of an inch in years of observation (and several North Sea crossings) but it is easy to imagine the larger piece sliding off its perch in a heavy sea, dropping 4 inches to the hull, and hardly slowing in its progress to the sea bed as it punches a hole through the garboard plank. I suspect a good sized hole low down at the bow in a heavy sea is not a good idea!
Must secure it (the surveyor advises remove it) but how? Punched steel straps and bronze screws? A bit ugly and lead/steel/bronze sounds like I am making a battery. Would love to splice some form of strop and lash it down but to what?
Could I - and don't everybody scream at once - stick it with epoxy? Does this work metal on wood?
 
Steffan,
See previous post "lead for lead".
I've been working on collecting anough lead to cast into ingots to replace the cast iron pigs which are my trimmable ballast and would only comment that movement is the least of my problems. The soles are well screwed down. The only floor hatch is over the bilge sump where the pumps live and there's no ballast in that area.
Theoretically replacing iron with lead will reduce volume and make more space for movement, but at the moment they are well packed in.
Finding lead is a problem. The dea from the forum about collecting tyre weights came to naught... lead hasn't been used for years. Roofers and salvors will sell - but only at commercial rates which per ton is nearly the same for scrap as for ingots.
I guess I will keep collecting and replace the iron as I can.
 
Have you considered building a square dam around the offending weight and pouring some concrete in? Keeping the contatc area to the wood reasonably small. You could use epoxy as suggested and lead will be glued as per any other metal but its sticking power will only be as good as the surface its stuck too, so all that damp old wood in your bilge might not be the best surface to stick to. Obviously you will need to work out what happens with an excess of concrete might do to your trim.Fine aggregate 2.4T/m3 FYI
 
Interesting post as I have 8 x 50kg lead ignots for trimming in my bilges. They are not fixed down but lie on rubber backed mats.I have often thought of how to secure them although they don't budge even when sailing at 20 degrees.
 
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