plating in aluminium

[Stuarth44]

We had no CAD when I was younger, hitting 69 this month
I would be happy to assist anyone wanting info from forming to welding and other stuff, gratis
I have many old pics, kick off with a couple

[Stuarth44]

that is me with dar hair, and Alan Paulsen an excellent tradesman, man absent on this build photo Ralph Fergussen a very skilled man
All from Waimauku NZ

[Stuarth44]

Me plating Marimba Mummery,
I was so daft then I built her upside down

[Matt Johnson]

Nice work Stuart! Love to see photos of someone else doing the hard work.

Matt

[Stuarth44]

Originally Posted by funjohnson

Nice work Stuart! Love to see photos of someone else doing the hard work.

Matt

Thanks Matt

[DavidRobertson]

Hello Stuart,

I'd very much appreciate your advice on an aluminium keel problem. I have a 57' boat with a bolted on aluminium keel box constructed in 2008.

The keel box has been constructed quite well with good thickness plating and plenty of stringers. The box has been filled with lead, then welded shut. The shrinkage of the lead has meant that there are quite a few hollow areas between the outer skin and the lead. At some point in the past sea water has leaked between the two and there has been quite bad corrosion of the original welds.

We've now replated and rewelded all the bad areas and should be back to a watertight box. I am considering whether to try to inject resin into the void areas in order to remove any chance of recurrence. Any views on that ? I am thinking to drill & tap some pneumatic fittings through the skin, then apply a vacuum pump to draw the resin up through the voids. The disadvantage being that I will then have to seal up the various holes left afterwards.

Any input gratefully received from yourself, or of course anyone else who may have faced the same problem.

Thanks,

David

[GordMay]

Greetings and welcome aboard the CF, David.

[Stuarth44]

Originally Posted by DavidRobertson

Hello Stuart,

I'd very much appreciate your advice on an aluminium keel problem. I have a 57' boat with a bolted on aluminium keel box constructed in 2008.

The keel box has been constructed quite well with good thickness plating and plenty of stringers. The box has been filled with lead, then welded shut. The shrinkage of the lead has meant that there are quite a few hollow areas between the outer skin and the lead. At some point in the past sea water has leaked between the two and there has been quite bad corrosion of the original welds.

We've now replated and rewelded all the bad areas and should be back to a watertight box. I am considering whether to try to inject resin into the void areas in order to remove any chance of recurrence. Any views on that ? I am thinking to drill & tap some pneumatic fittings through the skin, then apply a vacuum pump to draw the resin up through the voids. The disadvantage being that I will then have to seal up the various holes left afterwards.

Any input gratefully received from yourself, or of course anyone else who may have faced the same problem.

Thanks,

David

Hello David
wow you are in a spot of bother
I left the forum, saw your post and rejoined
I have seen this problem much, in the 78 Whitbread PenDuick had same problem, her keel was spent plutonium waste, heavy
send me an email I will help you through this
rgds
Stuart

[Stuarth44]

2001 Mummery Aluminium Sail New and Used Boats for Sale - au.yachtworld.com
the finished product
sold once
wish I could buy her back?
No, cannot afford the upkeep

[HappyMdRSailor]

Originally Posted by DavidRobertson

Hello Stuart,

I'd very much appreciate your advice on an aluminium keel problem. I have a 57' boat with a bolted on aluminium keel box constructed in 2008.

The keel box has been constructed quite well with good thickness plating and plenty of stringers. The box has been filled with lead, then welded shut. The shrinkage of the lead has meant that there are quite a few hollow areas between the outer skin and the lead. At some point in the past sea water has leaked between the two and there has been quite bad corrosion of the original welds.

We've now replated and rewelded all the bad areas and should be back to a watertight box. I am considering whether to try to inject resin into the void areas in order to remove any chance of recurrence. Any views on that ? I am thinking to drill & tap some pneumatic fittings through the skin, then apply a vacuum pump to draw the resin up through the voids. The disadvantage being that I will then have to seal up the various holes left afterwards.

Any input gratefully received from yourself, or of course anyone else who may have faced the same problem.

Thanks,

David

Welcome to CF David!

I think your idea has very good merit as long as you don't have any active corrosion going on between the plating and lead???

And Welcome back Stuart! Nice stuff...

[Stuarth44]

simple, really the only way, you may THINK your tank is tight by just pressuring it and going round with soapy water,but this rarely happens, rare to get a complex weldment like a keel tight first time

[topmast]

I'm fond of melting old fashioned roofing pitch into voids. (Called petrified asphalt in the trade.) If you could heat the keel with small controlled bonfires hot enough to let melted pitch flow in top hole ( funnel) ,out bottom hole ,then plug low hole and continue to fill . Just a thought .

[Stuarth44]

Originally Posted by topmast

I'm fond of melting old fashioned roofing pitch into voids. (Called petrified asphalt in the trade.) If you could heat the keel with small controlled bonfires hot enough to let melted pitch flow in top hole ( funnel) ,out bottom hole ,then plug low hole and continue to fill . Just a thought .

yes good idea, specially if you have ingot lead, pitch would stop it rattling abt too
Whatever you do , that keel must be pressure tested before anything is poured in
In the big clunker steel boats we used steel punching s and then filled the box with used transformer oil
the old Dutch builders would go so far as to place a burning candle in there, make the last weld and then all the oxygen was used, I never saw this, just heard a rumour to that effect