View Full Version : Lead for keel
05-01-2011, 11:10 AM
A few pictures of this weekend smelting operation. I melted about 2000 lbs of lead weights into aa old roasting pan and some old bakery bread loaf pans. Originally I thought eh tire weights there not small should be to big a deal. Well it was lots work. I have about 1500 lbs of uncleaned weights left to melt and then I cast the waiting keel mold. Maybe next weekend. The rotating pipe spout work great I didn't even need a torch to heat the spout all I did was cover the spout with some metal hoarding to heat it up and melt what ever was in the pipe.
05-01-2011, 11:54 AM
HOw much does each of those disks weigh? What about the ingots stacked behind them?
05-01-2011, 01:56 PM
The ingots are 15 - 35 lbs each and the larger roasting pan chunks are 50 -100 lbs each.
05-22-2011, 12:47 PM
New pictures, and I've finally cast the keel. It went very fast, about 3000 lbs of lead melted in 1.5 hrs and it was done.
I used the dirt to insulate the mold to keep it warm while another batch heated up as I was just a little short it was still bubbling pretty strong when the second batch went in, so there were no issues as far keeping the pour as one and no layers. It was sizzling hot 5 hours after the pour.
05-23-2011, 07:00 PM
You've got more guts than I. I'd never have put that much lead on top of a cut up oil drum and then built a fire under it. Had that bottom drum buckled under the weight... or for whatever reason settled and tipped, it could've killed somebody. But, all's well that ends well. Nice job!
05-24-2011, 09:35 AM
Bob, Thanks, the actual tank the lead was put in was a 60 gallon thick wall pressure tank it had 6 - 2" heavy wall pipe legs around the tank with a 4' base it was solid as a rock. I did a loaded push test before the fire I could not push it over it was solid on the ground and did budge at all. The drums were placed over the tank to create a fire box and help keep the heat in along with the old metal roofing as an extra layer. The 3000 lbs lead melted in about 1.5 hrs. which I thought was pretty fast using wood only, no fans, blower or torches for the melt were necessary. I thought about using the drum on it's side but didn't like the idea because of structural concerns and the pressure tank was free and much stronger so I had less the be concerned about. As far as fumes went I had enough breeze that working up wind was easy. I will admit I was very alert on the day I cast the keel it was a one man job that was done in 2 hrs. Now that it has cooled I will remove the keel from the mold and match it to the keelsom.
I'm headed down east on Thursday visiting Herreshof Museum, Mystic Seaport and other interesting places for 3 days so it will have to wait until I return.
Bob that was my first thought too, but I think the drum is just a flame shield/funnel. You can see some sort of crucible inside....
Have you had a chance to open it up yet? Did it maintain a good surface or did you get a collapse somewhere? I am wondering how you dealt with shrinkage as the lead cooled...I would not have thought the small box on top would act as a large enough "bank"...or more precisely that it would have cooled and solidified before the primary casting. It's a nice rugged mold!
05-24-2011, 10:30 AM
I haven't opened it yet but I did tap the mold with a hammer it was solid all around. The sprue it drew from is about a 400 lbs solid block of lead which equate to 15 percent of the total weight of the keel. I did keep the block liquid with the tiger torch for about 30 minutes after the pour. I'm not sure yet but I think I got a good solid casting. The mold is 1/4 steel plate it held it shape perfectly and didn't distort the I could visibly see from the outside. Making the mold was a labour intensive process that took about 10 hrs. The Alerion keel no straight sides, all curves. Sand casting it might have been easier but I'm not set up to large scale, and steel was easier for a 1 off job and most likely cheaper.
Other options would have been $10,000 with shipping to Edmonton.
05-24-2011, 05:53 PM
Not to be a party pooper, but what are you going to do if the casting sticks in the mold? (I've had that happen with steel molds.)
Hi Alerion Sailor.
Good work! I'm curious about your "60 gallon thick wall pressure tank." Is that a freshwater well pressure tank, or a hot water heater? And how thick is "thick?" Welded joints? Galvanized? I'd be very interested to know how galvanizing put up with this treatment.
I'd also like to know how you accumulated that many wheelweights, and what, if anything, you paid for them. How much crud and steel clips and stuff did you have to skim off? Did you add any flux to the lead, or antimony? Also, how did you get the lead into the crucible? Did you load it all before starting the fire (volume doesn't look right), or add it chunk by chunk as the pour went along?
I'm particularly surprised that you didn't need any forced air to keep the fire going hot. Must have been pretty good firewood.
05-24-2011, 09:03 PM
I bet there is a thing of great beauty inside there!
05-24-2011, 11:15 PM
Bob, it may stick a little when I tapped it to see if it was solid every couple of taps I could here the mold let go of the lead inside. I'm thinking it should shrink enough when cooled it should drop out with a few taps.
seo, it was a steel freshwater pressure tank with welded seems, not galvanized. The tire weights I got from the local tire shops the truck shops were the best because the weight were large and small clips It took about 8 months to collect 5000lbs. For the most part I paid $12 - $15 per pale 120- 150 lbs per pale I think the tire like to fill the pale to the top just to see me sweat. It was loaded by yours truly before I started the fire. The first load filled the tank with about 2500lbs I melted it and then added another 450 lbs, so it was done in one big pour and a small one. I tried adding 35 lb bricks to the 2500 lbs of molten lead but the heat was to intense from the fire which made me drop the ingots creating a splash of hot lead droplets so that ended that, dashing away from the furnace to avoid a nasty lead burn seemed like a tricky game to play.. I started with 5000lbs of tire weights I ended up with 3800 lbs of clean lead so there was lots of junk in the ingot making process. I did not added anything to the molten lead I took chance on it being the correct mix of antimony in the wieghts. I used small 2-3" round pieces of Diamond Willow it took lot of them but they burn faster and hotter than big wood..it was seasoned for 3 years for this purpose, it burns real hot. The blast furnace I made with two outer walls to surround the crucible the first one created an excellent draft on it own which made intensely hot fire the flame were shooting out the top lid probably 12". the secound just help contain heat. It also made it a lot cooler to work around.
Alex, I hope so!
I may go and pop the top off the mold tomorrow time permitting.
05-25-2011, 05:06 AM
looks like you will have a perfect keel there.
05-25-2011, 05:33 AM
A picture of it when it comes out of the mold would be most welcome!
05-25-2011, 05:42 AM
Thanks for timely pics and wordage Alerion,
I'm collecting weights and making ingots at mo, for a future pour. I'll probably do a similar way to you to keep things simple but with a wood mould. About 500 kg (1200 Lb ) The shot down in side mould looks like there is a centreboard slot in your keel, is that so and how did you arrange for this to be removed?
A question and a suggestion:
Q: Did you rake the trash (steel clips, dirt, etc) off the top of the crucible before pouring your pigs (sorry, ingots) or just leave them there and clean out the crucible after it had cooled.
S: You might try taking a piece of steel channel and set it up to make a trough leading from outside your shroud in to the top lip of the crucible. That way, you could set a pig onto the trough, and use a long rod to slide it in to the lip, where it would tip into crucible, while you are away from the heat and any spatters of lead. I have worked around a crucible that had been built out of a retired spherical barge mooring buoy. The top had been cut off to make a loading and clean-out "lid", and then the lid would be put back on when ready to heat. There was also a piece of pipe, maybe 8" in diameter 6' long (or so), welded onto the upper side of the crucible (not on the removable lid). After the initial loading, pigs of lead were loaded into the crucible by sliding them down the pipe.
05-25-2011, 08:15 AM
Bernadette, I hope it turns fine if not I'll have to start over.
andrewpatrol and seo, I highly recommend the truck tire shops there are a lot less clips, I sorted thru each pale and removed the stems just because the bad smell when the rubber melts. I've been told that the stems are slicon bronze and I have a 10 lbs of SB truck stems. Something else I did was use the top of the pressure tank as a tray, when cut off and placed up side down it would sit in the top of the crucible and be loaded with tire weights. I drilled about 30 holes in it were the lead would otherwise pool when melted the lead could then drip down into the crucible leaving the clips and most of the dirt in the tray( I highly recommend this because the first 500lbs I melted were melted in a heated ingot mold and allowed cool after the dross and clips were removed this method produced a dirtier lead ingot. If you look at the picture of the loaded crucible you see the difference in the shinny ingot and the dirty ingots, using the tray to capture the dirt and clips produced much cleaner ingots). The dirt and clips could be easily dumped into a metal pale and then reloaded. You will have earned your days salt after successfully completing the task.
The wood in the mold is for the center board slot.
For safety sake always be cognisent of splashing lead, stay upwind of any smoke, wear proper gloves when handling the hot stuff and good welding leathers will protect the skin against the minor burns. If you build a tall tank like I did make sure the ground is solid and level and check to see if it is solid before melting.
This was not complicated it was more labour intensive. With a little common sense and moderate skill anyone could do it. I did the entre process solo and I actually preferred it because sometime too many feet get in the way.
Making a steel mold for Alerion required some skill and creativity forming the 1/4 steel plate, but for a 1 off production it was the best method for me.
05-25-2011, 05:48 PM
Thanks for sharing this with us. That's why I love this forum.
05-25-2011, 06:36 PM
The wood in the mold is for the center board slot.
Phew!! I was looking and looking for the centerboard slot 'plug' and I didn't see it anywhere. (I still don't. Where is it?)
I was thinking "Oh gosh, he forgot about the centerboard!"
Can't wait to see it out of the mold. Quite the job!
The "Tray" or drainboard, or collander, or whatever, is very clever. If you invented that, you should take a turn 'round the the stage so we all can clap.
05-25-2011, 08:01 PM
Seo I did invent it I quess here are some pictures of the keel out of the mold.
Slight cavity on this end
It shrunk 1/4" in 11'
Once I clean up the edges I think it will be perfect, I'm completely satisfied with the casting. There is some crud on the edges (rust from the mold) aside from that the surface finish turn smooth as the steel. I will remove the wood for the center board slot when I return from RI then I will match it to the keelsom. I should have too much to do. Drill holes and make up the bronze bolts and a lifting eye. I'm still following the plans and intend to with out any changes.
05-26-2011, 03:24 AM
that is a very good keel. well done. its excellent.
05-26-2011, 03:37 AM
Nice job ! thanks for sharing Y>
05-26-2011, 07:53 PM
I'd really like to see some pictures of your crucible and its "collander" top, without the tinwork around it. Your written explanation was very good, but it would be a good double check to see a picture or two
05-29-2011, 01:13 PM
05-29-2011, 04:01 PM
I'll post in about a week time. I'm in Virginia time today and will travelling to MIT, Hreeshoff Museum, Mystic Seaport over the next few days. I was really very simple one end of the tank cut off and flipprd over to sit up side down just like a collender would be used for spegetti. the melted lead finds it way to the hole and into the tank. It produces pretty clean lead.
06-17-2011, 09:59 AM
Here are the pictures of the collinder I made for the smelting furnace
Center board slot turn out nice as well as the notch for the CB pin.
06-17-2011, 01:18 PM
Now this thread should somehow be saved, stickied or archived somewhere so when people are doing keels we can post this link as a great method, idea of how to do it safely. I am thinking of the MAID thread and Bob Albers SUSAN where the pours went well but questions were asked and links to successful pours would be SO helpful.
Nice job, I really like the colander idea.
good bad or indifferent, but I have melted a few thousand pounds of lead over the years, usually in a large kettle on a turkey cooker, way too slow, effort intensive, but using a laddle you can skim off the slag very easily and effectively. The pigs you get are VERY clean, but with more effort, thus I like the colindar idea. Congrats.
Pics of the rest of the boat??
I really like the collander. Do you have a video of the whole process? I wonder if it might be improved by having a steel circular "fence" welded into the collander bowl, a little bigger in diameter than the circle of collander holes, with slots cut in along the bottom of the fence. The logic being that as the steel bits, dirt, and dross melted off the lead wheel weights, they would rise to the surface outside the fence, where they might be easier to skim off than right above the drain holes. At the same time, the molten lead would be flowing off the bottom of the pool outside the fence, and then draining down through the holes in the collander.
06-18-2011, 10:54 AM
Seo, that would work well, I did have to stir up the weights at least once for each load because the lead would pool in the clips so I used spade to stir it a bit. There was ussually and inch of dirt under the clips with each load that was easily dumped out. I never really had enough lead pool in the collander to float the weights and dross on the top because as it melted it dripped through the collander into the crucible.
One thing I would add is a hinge and pivot arm to the collander to assist with unloading the spent tire clips and dross over the side it weighed about 50 lbs with a second reload of weights. With intense heat rising up from the chamber around the crucible things were uncomfortably hot on occation when unloading the collander. I used vise grips on collander for temperary handles that could be removed so they were always cool when needed.
I have this perfect mold that could be reused to make more Alerion keels now. It work so slick and was a sinch to remove. I flipped it over and it lifted off the lead keel with no binding at all and ther was nothing to chip off the lead. The steel mold was as simple as it gets. I surprised myself when it was done how easy it really was. I have seen videos of someone using a sand casting method and jack hammering the mold to get to the keel, seemed like a lot of unecessary work.
Maybe there's a way to communicate to Alerion builders that you have the mold, and the expertise, and can provide castings at a competitive price. One of the comments of L.F. Herreshof (The designer of Alerion) was about the economies of scale. Sorry, but I can't remember where or when he wrote this, but I'm pretty sure I have it right, paraphrased as follows "with a small-scale supplier (lumber, castings made from scrap lead) if they have orders for finished product that exceeds the supply of low cost raw material (trees, scrap tire weights), then their advantage disappears.' This was the basis for his idea that a small building yard could compete successfully with the big boys.
06-19-2011, 12:54 AM
It make sense that cheaper material would be competitive, although don't think their are enough Alerion builders out there. It a lot of boat to build.
Next is preparing to drill the bolt holes.
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