Challenge: Ballast Alternative ?

[Alaska JD]

Thank you Delmarrey for the EXTREMELY complete list. I marvel at what I'm able to learn on this forum. I did notice that of the materials listed, Gold and Platinum have by far the highest specific gravity - thus proving scientifically that boats are indeed simply a hole in the water that we get to pure money into. The more we pour the more efficiently we are balasted

[Boracay]

Would it be possible to use a combination of lead and steel?

I'm thinking lead right at the bottom of the cavity, as much as you can afford. Shot in epoxy may work, or it's not impossible to custom tailor lead to fit.

Then put epoxy coated steel on top of that, held in place with cement.

I'd also consider putting the largest possible removable water tank as low as you can.

When I built my ferro boat (Hartley ROTC 32) it had significant weather helm in a blow. I ran into the sail plan designer at a boat show and asked him about this and he suggested adding a fair lump of lead to the bottom of the keel, so I'm guessing that more weight as low as possible could help, as long as it doesn't take the boat of it's lines, change the fore and aft trim or overload structural components.

One designer of boats for amateur construction used to suggest that a fair proportion of ballast be held back till after launch to assist in keeping the boat in trim.

[barnakiel]

Originally Posted by Boracay

Would it be possible to use a combination of lead and steel?

Boat specific probably. But there has been boats with exactly this arrangement.

b.

[fishwife]

Originally Posted by Boracay

Snipped....

One designer of boats for amateur construction used to suggest that a fair proportion of ballast be held back till after launch to assist in keeping the boat in trim.

I'd say this was fairly critical. It's going to be a right PITA if you have to start digging out ballast after it's set in whatever medium you choose.

P.

[captain58sailin]

How about depleted uranium? I hear that they are having problems finding places to store it? You could always use lead as a shielding and fill the core. You would have the only glow in the dark keel.

[delmarrey]

The other alternative is black sand Black Sand, What Is It? it's a by product of gold prospecting. It's almost as heavy as lead. When I use to gold pan (for fun) in Arizona I would collect buckets of black sand and I could hardly move them.

The only down fall is that it is magnetic but so is iron or steel. If you could locate a mining co. in your area you might be able to pick some up at a decent price. It wasn't on the list above because it's a combination of minerals. I don't know if it won't rust in salt water but if it were sealed in a water proof bags there would be no worry. You can just pour into the bags and drop them in.

Placer mining activities produce a concentrate that is composed mostly of black sand. Black sand concentrates often contain additional valuables, other than precious metals: rare earth elements, thorium, titanium, tungsten, zirconium and others are often fractionated during igneous processes into a common mineral-suite that becomes black sands after weathering and erosion.

BTW you would want to seal the bags in tightly some how in case of a blowdown/roll over.

[Lodesman]

Originally Posted by delmarrey

The other alternative is black sand . It wasn't on the list above because it's a combination of minerals.

On the list as:

Magnetite, solid 5.05 315
Magnetite, broken 3.29 205

[Mark1977]

hmmm, Black sand. I don't think there are any active gold mines left in my area,but i know of one that has been abandon. There are alot of sand and piles of round rock core samples, or left from drilling. Would black sand be somthing that may have been left behind as a byproduct or just disregarded??

[David M]

If the increase in weight does not increase the righting moment sufficiently, then I would not bother. Adding weight to your boat kills both upwind and downwind speed. Adding righting moment only increases upwind speed. You want to make sure the trade off is worth it. If the length of the moment arm is not long, then I would not bother because all you are doing then is killing downwind speed.

[lorenzo b]

i used concrete, it's so easy to put in place if you pump it,the forms are easy to build, completely fills the space, and will not shift. if you already have a concrete hull you can pour right against it.
Oh yeah, it's cheap.

[delmarrey]

Originally Posted by Mark1977

hmmm, Black sand. I don't think there are any active gold mines left in my area,but i know of one that has been abandon. There are alot of sand and piles of round rock core samples, or left from drilling. Would black sand be somthing that may have been left behind as a byproduct or just disregarded??

You'd be surprised with the price of gold now. Check with the local surveyor's/claims office.

Black sand is not a rock but sand only which is the last thing one gets before the gold in panning or sluice boxes. The largest chunk I've seen was about the size of a match head.

Black sand has a specific gravity of from 5 to 11, or 5 to 11 times the weight of water, depending on what is in the black sand. Gold, on the other hand, has a specific gravity of around 19 and platinum around 21. As you can see, gold and platinum can be two to three times the specific gravity of black sand, so you now understand how you would want to find black sand in order to find gold and other heavy metals.

I have a few nice samples I pulled out of Lynx Creek up by Prescott, Az back in the 70's. Some smaller nuggets I had a ring made up. Not to get off the subject too much here.

[klem]

I am surprised no one has mentioned rocks. That is the traditional form of ballast from centuries ago and can generally be found for free. Different types have different densities, obviously denser is better. You may not be able to find anything local that is dense enough but then again you may. Concrete can be poured over the top to seal things in. Rocks make good trim ballast just like small lead pigs.

[delmarrey]

Originally Posted by klem

I am surprised no one has mentioned rocks. That is the traditional form of ballast from centuries ago and can generally be found for free. Different types have different densities, obviously denser is better. You may not be able to find anything local that is dense enough but then again you may. Concrete can be poured over the top to seal things in. Rocks make good trim ballast just like small lead pigs.

The specific gravity of rock averages out at about 3 depending on it porosity, slightly more then cement. But then there are the gaps, even in crushed rock. That's why I say black sand.

[QUOTE by Gordmay]Golf Balls & Beer
GOLF BALLS & BEER:

Standing in front of his class, a philosophy professor picked up a very large, empty jar, and filled it with golf balls.

He then asked his students if the jar was full. They agreed that it was.

The professor then poured a box of small pebbles into the jar, shaking them so that they rolled into the open areas between the golf balls. Again, he asked if the jar was full. The class agreed it was.

Next, he shook a box of sand into the jar. Asking the same question, he got the same reply; “yes, the jar is full.”

Finally, the professor emptied two cans of beer into the full jar.[/QUOTE]

http://www.cruisersforum.com/forums/....html#post1840

Even in sand one could add a liquid.

[barnakiel]

Indeed. Some rocks are very heavy. Here we have a black volcanic stuff that is way heavier than concrete - probably huge metal content or something.

b.

[lorenzo b]

the streets of San Francisco were paved with ballast stones from abandoned ships as the crews went of to search for gold.