Saturday 4 May 2013

Keel Foo Yung.... (stir-fried)

Mr Wong and Mr Kwong, stir frying the lead, in the back-streets of Kowloon


It's been a while since the last post.   I've not been idle (well... not too idle...), just that I wasn't sure how I was going to make the lead ballast-keel for this little Somes Sound 12 1/2.  Both Dave in California and Embla in Ireland (links at right) managed to cast the keel well enough, so that was an inspiration.  

But here in Hong Kong, I faced a peculiar challenge: first, that there's very little scrap lead around -- most is immediately shipped to China. Second: that there's no foundry that's willing to melt lead: again, that's all moved to China.  So I had various versions of Plans A, B and C....*


Plan B was to do the pour at my place in Discovery Bay, but at the last minute, and thanks to yachting mate Frank Pong, I got the address of a little place in Tai Kok Tsui, in the back-blocks of Kowloon, who, Frank said, would be willing to melt and pour up to 300kg of lead. So revert to Plan A, version 3.0....
So, off I head to meet up with Mr Kwong, who doesn't speak English, but does speak some Mandarin (which I speak), so we got along fine, though his Mandarin is what I'd call "Canto-rin" -- heavily Cantonese-accented Mandarin.  
Courtesy of neighbour Steve, who has a van (and who helped me with the first lamination of the inner stem), we took the mold to Mr Kwong Friday a week ago (26 April), and set Monday last (29th April) as the day to do the melt and pour.
Result: GREAT!
It started slow to be sure, and I wondered at one stage if we were going to have to give up.  Mr Kwong only using flame from above and one little bottle like you use for the lamb hotpot.  I said flame was needed below (industrial strength restaurant-style) and though he agreed, he didn't do anything about it, as he obviously didn't have the requisite gear. So he headed off round the corner and came back with another large gas bottle and flame thrower and with that, managed to melt the lead in reasonable time.
The lead was poured into the mold with Mr Kwong's soup ladle... it worked fine!  
We kept at it: pouring ladles of lead into the mold and melting bits of lead as quickly as possible so that the lead in the mold wouldn't be too hard -- if it gets too hard, the next layer poured in the mold won't "stick" to the one below.  
We kept at it until the lead was up to the line I'd scribed on the mold for the highest level of lead. Also, we'd pre-measured 265 kg of scrap lead and that was what we melted.  All of it.
It was starting to look good when the amount of lead we'd measured and melted matched exactly the line I'd marked on the mold.
Then we weighed it on Mr Kwong's scales: 265 kg was the design weight.  The actual weight: 263.99 kg!  Pretty good, I'd say! 
Photos follow...

Arlene works on the mold.  It's 1.5" pine.  The plans call
for 3/4" to 7/8".  I would't have considered 1 1/2" if Paul
in Ireland hadn't used it successfully.  It takes a bit of bending,
with clamps, but does so willingly, and worked fine.

I decided to follow Dave and put in copper chaser tubes
for the through bolts.  And following Dave's advice, we
put sand in the tubes, to stop the lead bubbling up into them.
Here is the mold finished, with braces to bring the pine into
the design widths along its length, and also lined with
fireproof paper, as per Dave's suggestion.

Change from the Plans: the sides are taken down to the bottom of the
mold, rather than being fitted to the bottom plank at the top (if that makes
sense): ie, instead of screwing in from the bottom, we screwed in from the sides.
That seemed easier to me, and it was so.  It also ensured there were no leaks of
molten lead by caulking the joins with the fireproof paper.

This is Mr Kwong's shop, Sheung Yip, 72 Oak St, Tai Kok Tsui, Kowloon.
The area is all metal.  Mr Kwong has lead, rolls, scrap, lumps; Zinc; Aluminium...

Mr Kwong burns the lump of lead scrap, while Mr Wong gets ready to
funnel sand into the copper tubes: to stop the bubbling in of lead, which
Dave said was a problem when he cast his keel.

And here we are creating the new dish -- "Keel Foo Yung".  Using restaurant
utensils: a huge Wok, spatula, slotted spoon, soup ladle...

Measuring the weight.  (the mold had been pre-weighed).
After a bit of arithmetic: find that we're about 1kg
within design weight.  I'm stoked!

At this point the lead is still hot and steaming, though
you can't see it from the picture. The fireproof paper
was not really needed for this mold, with the thick and dry
pine that we use (maybe more necessary if you use plywood, as
Dave did).  There was minor burning of the wood, as the lead
poured in, a pleasant smell of burning pine and a bit of smoke.
Thumbs up!  Mr Kwong, Mr Wong, and our Noel, celebrate the
successful pour.


* Plan A: find a foundry in Hong Kong to melt and pour the lead.
   Plan B: melt and pour the lead at home.
   Plan C: forget about lead: throw a bunch of stones in the bottom of the boat, like the Vikings did in their longboats.

5 comments:

  1. Dave's comment, 7 May, on "About this Blog", cross-post below....
    Just checked your blog Peter. The method you used to melt and pour your lead was very interesting. Just goes to show there is more than one way to skin a cat. I am working on fitting out and building a mast jig to transport the mast horizontally on the trailer. Hope to add a new post shortly.

    Dave Johnson

    ReplyDelete
  2. Thanks Dave,
    Yes, it was quite an experience.
    Look forward to your new post, always fun and instructive!
    I'm now in Vladivostok, where the water is just 3 degrees: gotta be very brave to sail these waters!
    cheers
    peter

    ReplyDelete
  3. Thumbs Up! Yeah Boyz! Mr Kwong and Mr Wong - "KEEL Fu Yung" in a Huge Wok, Spatula, Slotted Spoon and Soup Ladle = successful Pour of melt down Lead. Phew! that was Amazing. Forse Stoked! Now Noel be busy fitting lead ballast Keel in your Absence in prep for "Gabrielle's Launching. Have FUN "back on the Road again with Gordie and Cobbers in Vladivostok. Splash! 3 degrees brrrrrrrr!!!!!

    ReplyDelete
  4. Well done Peter...seems that your approach may have worked even better than my large cruicible and barrel approach which possibly overheated the lead, as I can see that your mold burned less than mine. Hope it turned out ok!

    ReplyDelete
  5. Thanks Paul, yes worked out ok, as you'll see from posts I'm about to do...
    cheers
    peter

    ReplyDelete