Pouring lead into holes into lead bulb or just hammer in strips?

I need to fill in three drill holes as well as a space where a stainless plate was located in a lead bulb. The bulb is of course currently not attached to the keel blade. I only need about 5kg which isn't much but then it's also only a light sailboat but already on the tender side.

Would it be better to pour molten lead into the holes and gap or could a solution be to hammer in little lead strips given lead is very malleable?

If I go the molten lead route an issue is sealing the bottom to stop the lead pouring out of the drill holes on the other side. What could be used as a stopper available from a local hardware? The holes are 14mm diametre.

Thank you

 

A squat tapered wood plug could be use to seal the bottom of the 14mm (5/8") holes and fill from the top. Once cooled, remove the plug and pour lead into those cavities. The plug will char a bit but should hold for a pour.

Was the 5kg weight bought pre-made? At that size I would consider melting down the whole works and re-molding if I had the molding pattern, foundry sand, and a little extra lead.

 

Hi boony, a no heat method: something to block holes at bottom and hold the weight, lead shot, sinkers, chopped wheel weights, chopped flashing, and epoxy resin. Wet lead pieces with mixed epoxy resin, pour lead in till full, top up with epoxy to secure it and to fill voids. Just make sure there is no corrosion in the lead.
If using molten lead, a chunk of cold steel will solidify the first short lead pour, maybe an inch or two thick, and when cold again pour in the rest, blocked by the cold lead plugs.
I'm sure there will be other viable suggestions soon too.

 

Thank you both for the excellent thoughts. I hadn't even thought of using an expoxy solution. The 5kg is just the amount of lead estimated to be required and has yet to be be bought. On reflection it may only be about 2kg. I was not aware that lead coukd be subject to corrosion problems. I imagine the issue here would be the corrosion leading to the epoxy/lead plugs loosening and dropping out?

Any thoughts on how to plug the holes on a semi-permanent basis where the nuts will be recessed in the bulb? This is on the underside of the bulb and how it's attached to the keel blade.

I don't expect to need to separate the bulb from the keel blade ever gain but if these recesses are permanently plugged and sealed then it would be very difficult to locate and undo the nuts without major sugery. When I bought the boat these recesses had been were left open and would have a causd a bit of turbulence to the flow of water over the bulb. I was thinking threaded plastic plug screwed into the lead. The diametre of the recess is 25mm and is the same in depth.

 

I mention lead corrosion simply because glueing anything with any corrosion on it isn't a good idea; and also lead oxide is a poison, so be careful when cleaning it off, even wear a mask and gloves. The white stuff on the lead in the photo is probably lead oxide, or paint. The bolt heads / nuts and recesses could be sealed with sikaflex, and holes smoothed flat. It's less likely to be pulled out like silicone sealant, but can be dug out if needs be.

 

Another great reply. Thank you!

 

I worked on a (wooden) boat over the summer with a class (as a student) and we were overjoyed to find out that the keel lead was through bolted with bronze rod and nuts on both sides.
That keel will need to be dropped and re-hung as part of the process and some rods had to be cut to remove floors so there is still hope.
I would encourage a solution that allows servicing the attachment hardware, the above idea with Sikaflex sounds great.

 

How about lead shot in epoxy? Round shot pack densely. Sold in bags or 25 lb. and up. About $2.00/lb.

 

Some years ago I cast some lead counterweights for a couple of wingsails. It was an interesting and educational experience. If I was to do again today I'd go the lead shot and epoxy route.

 

In the end I used melted lead shot. An earlier poster also mentioned lead shot and epoxy and that would have been the next next solution if I wasn't able generate high enough heat to melt the shot.