Casting a keel

[pmagowan]

Has anyone ever cast a keel or seen it done? I was wondering if it was something that could be done DIY. It could be cast of steel or lead or it could be a combination. It might not even be necessary to cast it as you could build a hollow steel structure and fill it with lumps of lead and a cement. Forgetting that it is bonkers what do you think? P.s idea is for a circa 40' with long fin keel.

 

[MrB]

Has anyone ever cast a keel or seen it done? I was wondering if it was something that could be done DIY. It could be cast of steel or lead or it could be a combination. It might not even be necessary to cast it as you could build a hollow steel structure and fill it with lumps of lead and a cement. Forgetting that it is bonkers what do you think? P.s idea is for a circa 40' with long fin keel.

How are you going to obtain the 2800 odd degrees heat to cast steel DIY??? :ambivalence:

 

[Rigger Mortice]

Lead, yes.
Iron, no.
(Well, it could be done but it would be a major project. Doing it in lead would be a big enough job)

 

[Lucky Duck]

I'm intrigued by the concept of using cement for the keel, maybe all that is needed is some shuttering plywood and a readymix lorry?

 

[2nd_apprentice]

I only ever read of welded steel keels filled with lead for DIY construction. Time consuming and unhealthy. Probably worth outsourcing.
No idea how you'd build a ferro keel but since my (wooden) boat has one it's obviously possible. Jay Benford published several books on ferro construction.

 

[yachtorion]

I wonder if it might be easier to make a keel from GRP, perhaps integrated into the hull, and just fill it with shot/scrap and epoxy, as per the Hurley 22 etc.

 

[fergie_mac66]

lead keel

Has anyone ever cast a keel or seen it done? I was wondering if it was something that could be done DIY. It could be cast of steel or lead or it could be a combination. It might not even be necessary to cast it as you could build a hollow steel structure and fill it with lumps of lead and a cement. Forgetting that it is bonkers what do you think? P.s idea is for a circa 40' with long fin keel.

believe it or not PBO used to be really good and the readers could doanything . I do remember an article a good few years ago about somebody building a yacht and casting hisown keel(lead) seem to recollect he took a couple of days with several helpers there were a good few pictures what issue ? there you have me a cannot remember twas a long while back the mags are dumbed down now so I doubt it will be covered again!

 

[Sniper]

Larry Pardey's book 'Details of classic boat construction' has a very detailed account of how to go about casting a lead keel.

 

[Rum_Pirate]

Philip Walwyn built KATE and cast the 11.5 ton keel in his garden in 2006.

The lead was made up of old lead batteries, old keels from smaller yachts, various bits, pieces and donations of lead

Melted in an iron container.

Took a while to start melting then quickly melted. lots of impurities has to be skimmed off.

The lead was poured through a spigot directly into the mould that had been constructed next the the smelting pot.

Can't remember from what material he said he made the mould.





PS Philip is sailing solo across the Atlantic on KATE at present but will ask him about the operation when I next speak to him.

 

[lpdsn]

Has anyone ever cast a keel or seen it done?

I have a suspicion that my brother cast the lead keel for my boat. All he knows is that they were being exported to Germany, but it was around the right time. I've meant to get him to look at it when the boat is out of the water to see if he would recognise it.

It was a commercial operation though and even then he left because he was starting to suffer from lead poisoning.

 

[Tranona]

Has anyone ever cast a keel or seen it done? I was wondering if it was something that could be done DIY. It could be cast of steel or lead or it could be a combination. It might not even be necessary to cast it as you could build a hollow steel structure and fill it with lumps of lead and a cement. Forgetting that it is bonkers what do you think? P.s idea is for a circa 40' with long fin keel.

Many different ways of making a ballast keel, some of which are suggested by others. Long, shallow keels are relatively easy to cast in a pit in the ground, but deeper and more complex shapes require a more sophisticated mould. Melting and pouring several toms of lead is not a trivial task. Steel casings filled with lead are a viable alternative - you can find a detailed explanation of that method by naval architect Dudley Dix on his website.

 

[DownWest]

There have been several threads (with photos) over on the Wooden Boat Forum. One that comes to mind was of two brothers casting the keel for an Oughtred Grey Seal.

Formwork is usually wood, occasionally metal. Best buried in the ground. Old baths or heating tanks for melting pots. I wanted a more profiled plate for my Dix CH21. So doubled the thickness and fabricated a hollow NACA foil in 4mm steel. Not finished yet. Needs galvanizing and filling with lead to the design weight. Melting pot is a 13kg gas cylinder with a big gas burner. It is best to weld a spigot low down (watering can style) so as to pour the lead from the bottom, leaving the dross on top. One method is to use a steel case and dump in lumps of lead, then pour in molten to fill the gaps. A 40fter keel would be quite a pour in one.
Our 27fter had two cast iron half bulbs hanging on fabricated steel pylons with a steel c/plate, giving a decent E. Coast draft of 3ft/6ft. The gap from the hull to the bulb was given a foil fairing. Casting iron is relativley cheap, esp if you supply the plug.

 

[Novachris]

I fabricated a pair of bilge keels a long time ago from mild steel plate, they were for a kestral 22. The needed I think, 5 holes top and bottom for the keel bolts, and a recess in the bottom for the nuts. I then had them galvanised inside and out and then filled them with leadshot.
I think we managed to get the 250kilo required weight in to each keel, took me an afternoon. It also helps if you have contacts in the industry to get the outside work done.
I put them on the boat for the guy, and she sailed as good as ever, apparently she is still going strong 20 years down the line.

 

[pmagowan]

Thanks for the replies. Getting the heat to melt anything is the easy part. The difficult bit is the bulk required. I don't want to reinvent the wheel so any experiences are useful. Lead, of course, would be the easiest to melt but I presume that it either has to be encapsulated in something or have an internal framework to give a strong point to attach it. Or perhaps you just need a decent washer on the bolts! Lead probably offers better performance that steel anyway as the weight can be situated lower. If I did this it would onlybe once so I am not too worried about lead poisoning.

 

[Sandy Bottom]

A good source of lead are the balance weights off car wheels - you can often get a deal with some local tyre replacement shops to save them for you (you only have to beat the scrap price by a tad) - a further benefit is that the balance weights already have the 3-4% antimony in them so you don't need to bother mixing it. Being small lumps they are also easy to melt - you just keep chucking them in gradually.

These guys have been acknowledged experts for decades - they might speak to you - they always used to be nice folks but I haven't dealt with them for over 20 years.

http://www.ironsbrothers.com/index.html

 

[30boat]

A good source of lead are the balance weights off car wheels - you can often get a deal with some local tyre replacement shops to save them for you (you only have to beat the scrap price by a tad) - a further benefit is that the balance weights already have the 3-4% antimony in them so you don't need to bother mixing it. Being small lumps they are also easy to melt - you just keep chucking them in gradually.

These guys have been acknowledged experts for decades - they might speak to you - they always used to be nice folks but I haven't dealt with them for over 20 years.

http://www.ironsbrothers.com/index.html

Car wheel weights are now made of zinc it appears.EEC regulations.

 

[Sandy Bottom]

Sorry if that is the case - I'm getting old!

Hmmmm... Anodes....

 

[30boat]

Sorry if that is the case - I'm getting old!

Hmmmm... Anodes....

There's always an upside...

 

[DownWest]

A good source of lead are the balance weights off car wheels - you can often get a deal with some local tyre replacement shops to save them for you (you only have to beat the scrap price by a tad) - a further benefit is that the balance weights already have the 3-4% antimony in them so you don't need to bother mixing it. Being small lumps they are also easy to melt - you just keep chucking them in gradually.

These guys have been acknowledged experts for decades - they might speak to you - they always used to be nice folks but I haven't dealt with them for over 20 years.

http://www.ironsbrothers.com/index.html

I sat next the CEO of ironsbrothers on a plane not so long ago. Thoughily nice guy. They cast quite a few of the French keels.

 

[Sandy Bottom]

I have also used these (set in resin) - but they are probably made of recycled cheese these days;

http://www.alibaba.com/product-detail/Elevator-counter-weight_318837821.html