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[Ted_H]

I've always waited until almost the end of a build before ballasting my boats, this can though at imes be quite tricky to get the right weight in the right place for the boat to trim properly.
 I have thought of adding the ballast before the decks go on but leaving a bit of weight out to allow for fixtures and fittings...
 How does everyone else do it?. plus I've often used bits of scrap. bolts, bundles of nails to trim .. sheet lead is far to expensive these days, and no church roofs nearby to get any from.... what does everyone else use.
 
Ted   

[GAZOU]

will see the mechanic and ask the old weights to balance car wheels.
Remove the iron
Melt the lead outside the house to give it the form

[Pat Matthews]

Earlier the better. I have even done the calculations for exact weight distribution BEFORE the build, but that's a lot like work.


Seriously, I do float tests as soon as the hull is watertight, to establish a weight budget. I can weigh the topside bits as I go along (more important on smaller models), and subtract that from my ballast budget. But this also lets me see WHERE the ballast needs to be placed, so I can allow for that in the early stages.


I prefer to build in "ballast tanks" to accept my favorite ballast, lead shot. The tanks take on various forms, but they all allow containment of the ballast without resort to loose "shot bags" and pouring resin around the shot, etc.


Pictures of my tanks at:
http://www.rcgroups.com/forums/showthread.php?t=1769388

[Shipmate60]

My preference is to ballast with batteries so make a  rack that the batteries can sit on and be mover for and aft.
When the correct position found stops fitted to keep the battery in place but removable before lifting.


Bob

[Bryan Young]

Surely this all depends on the physical size of the model.
I’d really like to see “Nemesis” answer this question; but in a nutshell, his philosophy during a build is that the weight of anything above the waterline has to be doubled by the weight below the waterline. It seems to work very well for him.
For my (larger) models I don’t really have a stability problem. Build the entire model, build a “test tank” and then stop the thing capsizing. This can sometimes take 80 lb of additional added weight. As I said, it all depends on the size of the model! BY.

[html]

Like Bob I use batteries as my ballast, they can be moved around and wired up correctly extend running times
 
Brian

[sparkey]

  I agree batteries are best, why put lead in a boat when with a little thought you can put batteries where weight is needed and extend the run time of your model, more run time=more pleasure,happy sailing,Ray.    

[Pat Matthews]

Ah, but there can be a good reason: When your model displaces 70 pounds, you may not want to invest in that many batteries!


As in my 5 foot Foundation Franklin, even a huge 20 pound, 26 amp-hour battery wasn't enough ballast, plenty of lead was required too.




BTW, my favorite ballast is lead shot (and is that readily available in the UK? That's one advantage of our 2nd Amendment, plenty of shooter's supplies around here). But round shot has a 70% fill efficiency, bringing the net density to that of solid steel, for what that's worth...

[Capt Podge]

Whenever possible I go down the "batteries" route. I would suggest this to be a good way to recycle dead batteries. Obviously, this can depend upon there being sufficient room within the lower confines of the hull and of course the physical size of said batteries.
 
Incidentally, if you're circle of friends happens to include an alarm engineer / technician, they can be a good source of "used" batteries. More often than not they are obliged to replace part-worn batteries when carrying out inspections and some batteries will still have some useful life left in them 
 
Where space is at a premium I tend to go for flattended out lead.
 
For the benefit of any novices out there - Make sure your ballast is placed as low as possible in the hull and in any case, secure it below the waterline - I speak from experience here, there's no fun in watching your pride and joy turn turtle and disappearing under the oggin.
 
Regards,
 
Ray.
 
 

[Shipmate60]

A 70 lb model even easier and cheaper.
Car or motorcycle batteries so much cheaper than gell cells £ per Ah.


Bob

[cjcj121]

I use lead sheets that are easy to shape and fix where i need them . I usually try and have the ballast worked out before i put the deck on . Annoys the hell outta the wife when i commandeer the bathroom for the afternoon for testing purposes .

[guitar man]

Hi
On the model that I am building at the moment I have ballasted before fitting the deck  as some of it will be out of reach after the deck is fitted, but have room to add more after to final water line. As for ballast I have tried a new approach of using stainless steel slugs (a waste product after holes are piecered  in sheet metal components where I work so unlimited supply, for now anyway). I line the area where they are to go with cling film and then resin in place this allows them to be remove if needed but remain a tight fit so they wont move, seems to be working at the moment ! Not as heavy as lead but no cost.

Regards Tony

[nemesis]

Hi, I start by marking the waterline on the new empty hull, taking it to the lake and loading the lead in until it is down to the mark. Take it out and weigh it, say example it weighs 21lb, then 14lb goes below the deck and you have 7lb in which to deck and build the superstructure and fittings. It is the old rule of " two thirds." This system has worked for me for years. IMHO. Nemesis.

[Buccaneer]

Similar to Nemesis I mark the waterline on the brand new hull, and then mark it to the inside of the hull using a waterproof marker. Chock the hull securely on the kitchen worktop, with the waterline horizontal, and fill it with a measured amount water up to the waterline. Each litre of water required will translate to 1 Kg of all up weight for the finished boat. This gives a good guide to the final weight of the boat, and by weighing as many bits as possible, and a little guesswork for those you can't, you have a guide as to how much lead ballast may be required.
 
If you want to go further float the hull, with the required amount of batteries and ballast to get the required displacement. This will help you get some ideas, and options, on distribution within the hull.
 
John