Today's wheelweight melting session showed me some realities

[JimGnitecki]

In other threads, I have mentioned that I was given maybe 80 to 100 lb of really old wheelweights (hereafter referred to as "WWs" to save typing) - the supposedly "good" ones from over 30 years ago, before WW makers started using a lot of Zinc which makes modern WWs pretty much unusable. But, today I discovered some of the realities of using even these "good" WWts.

I had previously washed ALL the WWs I was given using a water with Dawn dish soap solution. With the solution and the WWs inside a heavy duty thick industrial plastic bin, I sloshed the solution over the WWs back and forth by tipping the bin from side to side, prpducing a washing action similar to how a home clothes washer agitates clothes to clean them.

Then, I rinsed them very thoroughly with a pressure nozzle on our outside garden hose.

Then, I let them dry several days in the garage to eliminate ANY trace of water which could disrupt my melting session by allowing the appearance of the Tinsel Fairy!

Yesterday and today, I have so far done 2 melting and purification sessions, where I melted the WWs, extracted the clips from the melted WW alloy, and then fluxed until I had what looked like pretty pure alloy without any appreciable remaining impurities.

The first reality I learned in doing so, was that yes, a cold mold does cause wrinkling of any Lead alloy poured into it, verifying why we get wrinkled bullets at the start of our bullet casting sessions. In the photo below, the ingots that show wrinkles were the ones cast when the ingot mold was cold. The ingots that do NOT have wrinkles were poured in 2nd or 3rd pours into molds already preheated via prior pours into them minutes beforehand:



The next reality is that the GROSS weight of any pile of WWs is NOT an accurate predictor of the NET usable WW alloy you will end up with!

Between yesterday's and today's 2 melting and purification sessions so far, I ended up with this stack of WW ingots:



That's 26 ingots of varying weights. It LOOKS impressive, but it is only a net weight of 21.9 lb of Lead alloy.

That's because those 2 melting sessions ALSO produced these 3 stacks of WW clips, dross, zinc WWs, and some Lead alloy that had to be skimmed off the molten Lead in order to get ALL or at least most of the impurities and have only a clean Lead layer on top of what was in the pot:



Those aluminum "plates" the clips/dross/lost Lead are sitting on are each 6" x 6" aluminum TIG welding "coupons" I used up in TIG welding practice. The piles of Clips/Dross/zinc pieces/lost Lead"debris" on each of the coupon plates were about 3" high!

I weighed the debris (withOUT the plates), and it totaled to 8.1 lb !

So, here's the math:
Start with 21.9 + 8.1 = 30 lb of WWs. (I'm ignoring the insignificant actual weight of the burnt sawdust flxuing agent you see remaining in the 3 piles).
End up with a NET weight of 21.9 lb of Lead alloy (all hopefully good, with no Zinc hidden in any of it).
So the net weight of usable Lead alloy from a gross of 30 lb of WWs is only 21.9 / 30 = 73%.

And this is with the GOOD (over 30 years old) WWs. Any NEW WWs, where the precnetage of pure Lead is lower, are going to presumably be worse. And remember too, I had already removed all non-metallic debris, like dirt, tire valves, WW double sided tape, etc.

So, if you are actually PAYING a tire shop for its used WWs, keep in mind that you are getting only 73%, or LESS, of the weight you are paying for in actual Lead.

Jim G

 

[jdsingleshot]

I paid nothing for a 5 gallon bucket of WWs. Don't expect to need any more.

 

[dartor]

Your lead looks very clean. Your weight results are pretty much on par. I wouldn't have spent time washing them, all the crud floats to the top. I use a turkey burner and a large cast iron covered dutch oven to melt my lead. I put my ingot molds around the base of the dutch oven for a few minutes to preheat, tanks care of unwanted wrinkles.

 

[kmw1954]

That was fun. Wait until you get a chance to mine a pistol berm. Last time I did I removed 2.5 5gal buckets in about 70min... Total weight was 143#, after rendering down it netted just 96# of ingots. There was also about 28# of copper jackets.

 

[1976B.L.Johns.]

Cash in on your copper at the local junkyard!

 

[AJC1]

That was fun. Wait until you get a chance to mine a pistol berm. Last time I did I removed 2.5 5gal buckets in about 70min... Total weight was 143#, after rendering down it netted just 96# of ingots. There was also about 28# of copper jackets.

Well that covers what I should expect in losses. It's been raining and wet sand doesn't sift. Got none today. Your collection method seems far superior to mine. Only tried twice so far.

 

[.38 Special]

Here's 45 pounds of certified pure lead. I was feeling bad about paying three bucks a pound for it, but seeing the OP has made me feel much better!

 

[Hooda Thunkit]

I usually save the dross and throw it in the next pot to re-clean.

I save the dross from all the pot scraping and toss it in a coffee can. I'll sift out the obvious junk; the lightweight dirt and such, and keep the chunks of lead with garbage attached.
When the can is full I throw it in the next time I render down any dirty lead - be it WW or whatever.

The Zn weights I save also. I have a bucket full of them. Occasionally I render it down and cast it into ingots. Those ingots I use for trade. Some like to use them for trotline weights, some want cannonball material.
When looking for WW, sometimes I find a guy who says he uses them for trotline weights. If I can provide him with clean, drilled ingots ready to use it's easier to get hold of that bucket of lead.

 

[NIGHTLORD40K]

The vast majority of the wheel weights we use at the shop now are steel, sometimes painted, sometimes plasticoated. Ive seen brand new cars wth 3-4 strips of them at various points inside the wheel (they don't put them on the outer edge any more)- which tells me they really don't work very well since you can't concentrate as much mass in one spot.
In a couple years, I doubt you'll be able to find enough lead WW to make it worthwhile.

 

[JimGnitecki]

The vast majority of the wheel weights we use at the shop now are steel, sometimes painted, sometimes plasticoated. Ive seen brand new cars wth 3-4 strips of them at various points inside the wheel (they don't put them on the outer edge any more)- which tells me they really don't work very well since you can't concentrate as much mass in one spot.
In a couple years, I doubt you'll be able to find enough lead WW to make it worthwhile.

I think we are already at the point where current wheelweights are unusable. The only reason my buddy offered this batch to me was that he stopped bullet casting 30 years ago, and the only reason I accepted them was that they were all at least 30 years old! Even that old, look at the net versus gross weight.

He also got me 50 lb of "pure" Lead from another buddy of his who apparently has hundreds or thousands of pounds of it, BUT, as we discussed on another thread on this forum, 12 lb of that "pure" Lead was contaminated with visible Zinc.

I think we are getting close to the time where we'll need to either spend the time mining range berms (which our range disallows because our local very windy conditions require the berms to be solidly grass covered to prevent really serious erosion), or buy actually pure Lead from a metals supplier.

Jim G

 

[lightman]

I sort all of my weights before smelting because I melt batches of 350-400# and my burner will easily melt a Zinc weight that gets trapped on the bottom of the pot. I'm not actively hunting lead anymore but I still get a bucket from the local tire shop every 8 or 10 weeks. I've seen the lead yield slowly fall but I'm still getting an estimated 55-60% lead. I figure 12-15% loss due to clips. If I weighed the broken lug bolts and brake pads my lead % would be less but my 55-60% number is just for weights, lead vs non lead. I get them for free except for the cost of a couple boxes of donuts.

I use 7 cast iron ingot molds when I'm smelting scrap. I don't pay much attention to the first ones being wrinkled. About the 4th or 5th cycle I have to take a break and allow them to cool. Yeah, if I sold them I would like for them to be perfect but...............!

 

[mdi]

Lots of fun! Couple of thoughts, the Tinsel Fairy visits are when water gets under the surface of melted lead, like dropping a dripping wet chunk of lead in a pot of melt. The water expands rapidly, 7,000 times in volume turning to steam creating an explosion. Water dropped directly on top of a pot of melted lead will just dance around until it evaporates, harmlessly turns to steam. (when casting sinkers as a teenager, I worked on Ma's stove and when I heard her drive up in the drive way, I started cleaning up. Slowly pouring water directly on the lead pot to cool it sooner. No explosions, rarely whippin'.) I usually remelt the "skimmings" after I get a coffee can full to reclaim a bit of lead. May not be worth the trouble to just get a pound of alloy, but I'm in my shop doing casting stuff...

 

[kmw1954]

Subject of availability, here in the northern midwest lead has been outlawed for some years now. The scrap yards will not even talk to you about purchasing scrap unless you possess a hazmat license. Lead roof flashing is also just about nonexistent.

 

[hdbiker]

your melt isn't hot enough, and add a foot of 95-5 solder to your melt for better mold fill out.

 

[Jim Watson]

Anybody here casting zinc bullets?

 

[JimGnitecki]

Follow-up: I melted ALL the remaining WWs I was given, and learned more!

Here are the (worse) net versus gross numbers:
Gross weight of today's last batch of pre-cleaned wheel weights = 20.9 lb
Clips, dross, fluxing agent, and some actual Lead from fluxing = 8.4 lb
Today's NET weight of WW alloy = 12.5 lb
So today's net vs gross was 60%.

So, when I consider the FULL gross weight I melted in the last 3 days:
Gross weight = 30 + 20.9 = 50.9 lb
Unusable = 8.1 + 8.4 = 16.5 lb
Net = 21.9 + 12.5 = 34.4 lb
So the net versus gross in total for ALL my 30 year old WWs = 68%.

It makes sense that today's "final" batch had a worse net versus gross: As I grabbed WWs out of the container to melt them, I made no attempt to select them by size / weight. It was random. BUT, first of all, the smaller WWs tend to get to the bottom of any WW container, since they more easily filter their way down due to their smaller size ( as little as 1" length versus some 5" length WWs). Secondly, the CLIPS represent a much larger percentage of the total weight of a small WW than of a large WW.

Another thing I learned today was that using an 1800 watt electric hot plate to melt 20.9 lb of WWs in ONE batch was a bad idea.

It sounded good at first: Doing all the remaining WWs in one batch would prevent variations in actual content, and therefor actual HARDNESS, from on ebatch to the next.

BUT, when using a 6" diameter by 6" high stainless steel pot on an 1800 watt hot plate, trying to heat up 20.9 lb of WWs all at once, the combination of:
- lots of weight to heat,
- big pot overall UNinsulated surface area to radiate precious heat,
- only 1800 watts feeding the hot plate in total, and
- the hot plate's repetitive "shutting off the power" to keep the hot plate itself from exceeding its maximum design temperature,

it took about 2 hours to finally get the WW alloy and its clips and other content fully melted, so that I could first skim off the clips, and then flux the entire batch. And, once the level in the pot got very low, the alloy would try to solidify soon after I scooped it into the ladle and started pouring into the ingot molds (I had no room on the hot plate to keep the ladle preheated). But, I got it done.

I know that some of you will advise that I use a GAS heating device for faster results. Unfortunately, that is not an option for me. I insist on doing alloy melting and casting OUTDOORS for safety reasons (mine and the house's and garage's safety), AND because of the extreme wildfire hazards around here currently, the city flatly prohibits any open flames outdoors, and the fine is very stiff too.

The good news is that this ensured that the alloy in the pot never got really hot, staying at just under 600 degrees overall, and a bit higher near the bottom of the pot right over the hot plate. Apparently, it is important to keep the temperature below 650 F to prevent any Zinc that might be present from integrating itself into the Lead matrix, from which it cannot be extracted outside of commercial facilities.

I also learned that the infrared heat gun with its digital display did match the Lyman digital tmeperature gage pretty closely, despite the potential for reflectivity issues.

So, now i have about 34.4 lb of WW alloy in ingot form, plus about 36 lb of supposedly "pure" lead.

This is NOT much. First, I don't know how muhc of that pure Lead I can blend into the WW alloy. without making the overall combined alloy too soft. Secondly, when you are casting 500g buffalo bullets, you only get about 14 bullets per pound of alloy! So, I have only neough alloy in total now for a few hundred bullets.

Jim G

 

[AJC1]

Follow-up: I melted ALL the remaining WWs I was given, and learned more!

Here are the (worse) net versus gross numbers:
Gross weight of today's last batch of pre-cleaned wheel weights = 20.9 lb
Clips, dross, fluxing agent, and some actual Lead from fluxing = 8.4 lb
Today's NET weight of WW alloy = 12.5 lb
So today's net vs gross was 60%.

So, when I consider the FULL gross weight I melted in the last 3 days:
Gross weight = 30 + 20.9 = 50.9 lb
Unusable = 8.1 + 8.4 = 16.5 lb
Net = 21.9 + 12.5 = 34.4 lb
So the net versus gross in total for ALL my 30 year old WWs = 68%.

It makes sense that today's "final" batch had a worse net versus gross: As I grabbed WWs out of the container to melt them, I made no attempt to select them by size / weight. It was random. BUT, first of all, the smaller WWs tend to get to the bottom of any WW container, since they more easily filter their way down due to their smaller size ( as little as 1" length versus some 5" length WWs). Secondly, the CLIPS represent a much larger percentage of the total weight of a small WW than of a large WW.

Another thing I learned today was that using an 1800 watt electric hot plate to melt 20.9 lb of WWs in ONE batch was a bad idea.

It sounded good at first: Doing all the remaining WWs in one batch would prevent variations in actual content, and therefor actual HARDNESS, from on ebatch to the next.

BUT, when using a 6" diameter by 6" high stainless steel pot on an 1800 watt hot plate, trying to heat up 20.9 lb of WWs all at once, the combination of:
- lots of weight to heat,
- big pot overall UNinsulated surface area to radiate precious heat,
- only 1800 watts feeding the hot plate in total, and
- the hot plate's repetitive "shutting off the power" to keep the hot plate itself from exceeding its maximum design temperature,

it took about 2 hours to finally get the WW alloy and its clips and other content fully melted, so that I could first skim off the clips, and then flux the entire batch. And, once the level in the pot got very low, the alloy would try to solidify soon after I scooped it into the ladle and started pouring into the ingot molds (I had no room on the hot plate to keep the ladle preheated). But, I got it done.

I know that some of you will advise that I use a GAS heating device for faster results. Unfortunately, that is not an option for me. I insist on doing alloy melting and casting OUTDOORS for safety reasons (mine and the house's and garage's safety), AND because of the extreme wildfire hazards around here currently, the city flatly prohibits any open flames outdoors, and the fine is very stiff too.

The good news is that this ensured that the alloy in the pot never got really hot, staying at just under 600 degrees overall, and a bit higher near the bottom of the pot right over the hot plate. Apparently, it is important to keep the temperature below 650 F to prevent any Zinc that might be present from integrating itself into the Lead matrix, from which it cannot be extracted outside of commercial facilities.

I also learned that the infrared heat gun with its digital display did match the Lyman digital tmeperature gage pretty closely, despite the potential for reflectivity issues.

So, now i have about 34.4 lb of WW alloy in ingot form, plus about 36 lb of supposedly "pure" lead.

This is NOT much. First, I don't know how muhc of that pure Lead I can blend into the WW alloy. without making the overall combined alloy too soft. Secondly, when you are casting 500g buffalo bullets, you only get about 14 bullets per pound of alloy! So, I have only neough alloy in total now for a few hundred bullets.

Jim G

You might be able to insulate the sides of your pot to help retain heat. Welders cloth would be the best choice.

 

[JimGnitecki]

You might be able to insulate the sides of your pot to help retain heat. Welders cloth would be the best choice.

I don't know what "welders cloth" is, where to get some, and how to attach it to, and keep it attached, to a pot running at 600 or more frees F!

Silicone is commonly used as a heat resistant insulator, even to make cooking spatulas, but it can only take abut 400 or 450 degrees, not 600+.

Jim G

 

[AJC1]

I don't know what "welders cloth" is, where to get some, and how to attach it to, and keep it attached, to a pot running at 600 or more frees F!

Silicone is commonly used as a heat resistant insulator, even to make cooking spatulas, but it can only take abut 400 or 450 degrees, not 600+.

Jim G

6 ft. x 8 ft. Fiberglass Welding Blanket

Amazing deals on this 6Ft X 8Ft Fiberglass Welding Blanket at Harbor Freight. Quality tools & low prices.

www.harborfreight.com

 

[JimGnitecki]

6 ft. x 8 ft. Fiberglass Welding Blanket

Amazing deals on this 6Ft X 8Ft Fiberglass Welding Blanket at Harbor Freight. Quality tools & low prices.

www.harborfreight.com

Ok, now I know what you are talking about. We don't have Harbor Freight here in Canada, but we have Princess Auto, which is almost identical. I looked up those "welding blankets". They are NOT insulators. They are merely Fiberglass cloth that is rated to not burn through when hot metal sparks as hot as 1000 degrees F hit them. They are viewed as merely a barrier to stop moving hot particles, but not as a way of insulating a container.

I would need an insulating material that could be somehow fastened to the pot.

Jim G

 

[Bearded Phil]

Any NEW WWs, where the precnetage of pure Lead is lower, are going to presumably be worse.

I have no idea where you picked up that newer production lead based COWW are somehow worse that those from years ago (or somehow got in you head that they contain an alloy of lead and zinc?) but it's completely off base.

There are zinc COWWs, yes, that are much more common than lead based COWW these days but there are no lead/zinc alloy COWW. They're either a lead/antimony/arsenic alloy or they are zinc.

Lead is much more dense than steel, yes, so they majority of the weight you feel in any bucket of lead COWW is lead, but the steel clips do add up to a decent amount of weight. Most people report about 80% yeild of lead in ingot form. You coming up with 73% is probably due to inexperience in you skimming. There's a lot of lead that you pulled out with those clips and the other dross.

With more practice you can get better at this, but of course you'll need the COWWs to practice.

My advice is to hit up a few local owned tire shops in your area and try to talk to the owner or head manager. Ask them what they do with their scrap weights, and if you find one that says, "we just throw them away" you've hit the jackpot. Tell them you'll take them if their techs will simply put them all into a 5 gal buck or two, and if they agree bring in some for them. Then make a schedule to come in and pick them up.

Don't get picky, tell them to throw any and all scrap weights into the buckets. Don't ask that they only do lead, check for zinc, etc. The less work for them the better because they'll be more agreeable to help you out. Plus they may not even know what you're looking for and might save the wrong stuff.

I have a shop near me with this exact arrangement and I pick up the bucket every other Friday. I just dump the one in the shop into mine that I bring in, chat with the guys a few minutes and tell them I'll see them in 2 weeks.

Usually I walk out with half a 5gal bucket mixed of steel, zinc, polymer, other and of course stick on and clip on lead weights. This usually takes only 20-30 mins later that same night to sort out what I want and throw the rest into a trash bucket.

I average 5lbs/week (10lbs for every 2 week pickup) of just COWW and then a certain amount of stick on weights that go in a separate bucket. This is more weight in lead than I usually shoot in the same amount of time so I'm on a rolling surplus. So far since I started in the spring I've collected around 160lbs of raw COWW. Totally free except my time to sort and every now and then I bring in some sports drinks for the guys in the shop.

 

[AJC1]

Ok, now I know what you are talking about. We don't have Harbor Freight here in Canada, but we have Princess Auto, which is almost identical. I looked up those "welding blankets". They are NOT insulators. They are merely Fiberglass cloth that is rated to not burn through when hot metal sparks as hot as 1000 degrees F hit them. They are viewed as merely a barrier to stop moving hot particles, but not as a way of insulating a container.

I would need an insulating material that could be somehow fastened to the pot.

Jim G

They use a very simular material and plaster to insulate superheated steam in.power plants around the same temprature. They use plaster of Paris is home made kilns... in the old days they would have just used asbestos

 

[SingleActionAndrew]

I would need an insulating material that could be somehow fastened to the pot.

How about (race car) header wrap?

 

[JimGnitecki]

How about (race car) header wrap?

Hey, THAT's a possiiblity! That stuff survives in exhaust headers that are at 1300 degrees or more. Thanks for the idea!

Jim G

 

[jmorris]

Very large batches of lead make for consistency. It just requires a larger operation though. If you melted down 50 WW at a time, I would expect a lot more variation than if you melted down 5000 at a time or 50,000, or 500,000….

McMaster Carr has ceramic insulation that will work well past any temperature you will ever have lead.

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.

www.mcmaster.com