Small casting (alluminium) aty home.

[skyline1]

it is not at all a particular rare phenomenon. I repeat myself. Sugar has a melting point approx. 190° C table salt of about 800° C, both dissolve fine in water. Tungsten has a melting point of Three thousand odd °C if dipped into molten steel, it dissolves. A mix of 30% Tungsten and 70% Iron melts at 1529°C. ( I just googled that ) Carbon is another of the weird cases it can be at crazy high temperatures still solid, but is soluble in Iron just fine.
Antimony dissolves in Tin. ( SnSb solder )

This is very interesting, I guess it is all due to a "fluxing effect" where the metals do not chemically join to form compounds but they dissolve to form alloys.

Whilst on this subject, another metal to be avoided is Magnesium. Alloys of Magnesium, often with a really high Magnesium content, are sometimes used in automotive parts and can be fairly easily confused with Aluminium alloys.

The effect of accidentally introducing Magnesium into your melt can be highly dangerous. Magnesium can burst into flames which are almost impossible to extinguish. and can even explode.

If in doubt test a small piece by heating it to melting with a blowtorch.

Best Regards Mark

 

[timo_gross]

In all cases, an alloy with two metals that have melting temp "A" and "B", if you alloy them at exactly 50% each, the melting temp of the alloy will be (A+B)/2. If one is 3/4 and the other 1/4, then whatever the 3/4 temp is it will be (3/4A +1/4B), etc. for all possible quantities.

Hello Richard,

I am not quite sure if that is a rule. Never heard of it. I just grabbed a random diagram from goolge search. SnPb is easy, not much going on.
( the diagram is without source, do not use for accurate science )
Fe-Al diagram is horribly complicated, I would not be able to explain any of it.
If I followed your rule, provided I understood it correct. I end up with the following example 69.1%*327 °C + 30.9%*231°C = 297°C ?
But the diagram says. If you mix 69.1% Pb and 30.9% Sn it will melt at 183°C. That is the case for all eutectic systems, the mix melts lower than pure a or pure b.

one could determine the quantities by the melting temperature, if you were willing to test a bit.

Yes agreed, that is how you would make such a diagram. Melt the mixture and see what happens at what temperature. A very labor intense task.
However to stay with my example there is a mixture somewhere in the 40% Lead and 60% Tin that has exaclty the same melting point as pure Tin.
Silver and Cupper is another example for such a mixing behaviour (eutectic ). Silver melts at 962°C Cupper melts at 1085°C, a clever mixture can be as low as 779°C.

Cheers Timo

 

[Richard Hed]

Hello Richard,

I am not quite sure if that is a rule. Never heard of it. I just grabbed a random diagram from goolge search. SnPb is easy, not much going on.
( the diagram is without source, do not use for accurate science )
Fe-Al diagram is horribly complicated, I would not be able to explain any of it.
If I followed your rule, provided I understood it correct. I end up with the following example 69.1%*327 °C + 30.9%*231°C = 297°C ?
But the diagram says. If you mix 69.1% Pb and 30.9% Sn it will melt at 183°C. That is the case for all eutectic systems, the mix melts lower than pure a or pure b.
View attachment 125846

Yes agreed, that is how you would make such a diagram. Melt the mixture and see what happens at what temperature. A very labor intense task.
However to stay with my example there is a mixture somewhere in the 40% Lead and 60% Tin that has exaclty the same melting point as pure Tin.
Silver and Cupper is another example for such a mixing behaviour (eutectic ). Silver melts at 962°C Cupper melts at 1085°C, a clever mixture can be as low as 779°C.

Cheers Timo

I must have learnd it wrong. Oh well, thanx for correcting it.

 

[Aerostar55]

It turns out that ALL metals and a few non-metals will dissolve in all other metals. But to say this, has great caveats. They don't dissolve necessarily 100%. Some do, like that which makes up solders, brasses and bronzes and some aluminum alloys. That's what they are called, alloys, as you all already know. The amount that will dissolve is also temperature dependent. Try alloying something like iron with lead. ONe has a very high temp but the other is likely to BOIL at that temperature, even so, some lead is alloyed with steel. In all cases, an alloy with two metals that have melting temp "A" and "B", if you alloy them at exactly 50% each, the melting temp of the alloy will be (A+B)/2. If one is 3/4 and the other 1/4, then whatever the 3/4 temp is it will be (3/4A +1/4B), etc. for all possible quantities. This can be useful, as no matter what your alloy is, it will melt at a lower temperature than the highest melting metal.

I understood that the Egyptians used an alloy called electrum. THis alloy was supposedly an unknown composition but suspected of having gold and silver alloyed. (Probably it is an element NOT on the periodic table. Har har) Well, that is silly in now-a-daze ability to distinquish chemicals. The point being that if electrum were ONLY Gold and Silver, one could determine the quantities by the melting temperature, if you were willing to test a bit. Problem is, it might have some copper or some other metal as well, then it would get complicated. But the same law of melting still holds with more than two metals, that is, the melting temp calculated with the proportion of that metal . . . etc. etc. etc. If you have non-metals, I does not know the law. (I'm also a speeder and likes to break the laws.)

Aerostar: Could you show a pic of you foundry set up?

Yes, there is one small picture of my furnace in the previous post, but here is another one. Also I posted a YouTube video of my process
of casting a 7" flywheel

 

[MRA]

Hello Richard,

I am not quite sure if that is a rule. Never heard of it. I just grabbed a random diagram from goolge search. SnPb is easy, not much going on.
( the diagram is without source, do not use for accurate science )
Fe-Al diagram is horribly complicated, I would not be able to explain any of it.
If I followed your rule, provided I understood it correct. I end up with the following example 69.1%*327 °C + 30.9%*231°C = 297°C ?
But the diagram says. If you mix 69.1% Pb and 30.9% Sn it will melt at 183°C. That is the case for all eutectic systems, the mix melts lower than pure a or pure b.
View attachment 125846

Yes agreed, that is how you would make such a diagram. Melt the mixture and see what happens at what temperature. A very labor intense task.
However to stay with my example there is a mixture somewhere in the 40% Lead and 60% Tin that has exaclty the same melting point as pure Tin.
Silver and Cupper is another example for such a mixing behaviour (eutectic ). Silver melts at 962°C Cupper melts at 1085°C, a clever mixture can be as low as 779°C.

Cheers Timo

This is one of those embarrassing moments when a penny which should have dropped a long time ago (in this case, why is electrical solder - that is, the useful old tin-lead stuff which actually melts and makes reliable joints - comprised 60/40) - suddenly goes clunk as one scrolls through something random on the internet. Thanks for taking the time with that diagram!

 

[skyline1]

that is, the useful old tin-lead stuff which actually melts and makes reliable joints

I can't stand this modern Lead free stuff either ! and If you want REALLY good joints try Tin/Lead/Silver it's a bit pricey but it's absolutely beautiful to work with.

More H&S gone mad, we've been using Tin/Lead solders for well over 100 years and Lead water pipes since the Romans, but the whole world hasn't been struck down with Lead poisoning

Best Regards Mark

 

[timo_gross]

I wasn't quite finished , there are still a couple of buckets of scrap left to be processed . But unfortiunatly my "crucible" failed .
It was made from a fire extinguisher . I think it lasted 15 melts or so .
A bit dissapointing because it was quite thick walled steel . Maybe I should use a scrapped argon cylinder for the next one .
That should be 5 or 7mm thick .
View attachment 125802
View attachment 125805

Hello,

just found this quote in another thread. It proves my point considering wear of steel as melting crucible. Crucible crusade please do not get angry with me. I just cannot help it.

Greetings Timo

 

[timo_gross]

I can't stand this modern Lead free stuff either ! and If you want REALLY good joints try Tin/Lead/Silver it's a bit pricey but it's absolutely beautiful to work with.

More H&S gone mad, we've been using Tin/Lead solders for well over 100 years and Lead water pipes since the Romans, but the whole world hasn't been struck down with Lead poisoning

Best Regards Mark

A while ago I saw lead free Sn63Pb37 solder paste on one of usual suspect Chinese selling websites . Easier to work with.
No problems with the vegan neighbour and no problems with the process, but it seems to be sold out.

 

[timo_gross]

For some reason a double post, but seems I cannot delete it. That is the just punishment for quoting from another thread.

 

[SmithDoor]

Chinese may use a different word lead so it is lead free it just has 支, 枝, 桿.

Dave

A while ago I saw lead free Sn63Pb37 solder paste on one of usual suspect Chinese selling websites . Easier to work with.
No problems with the vegan neighbour and no problems with the process, but it seems to be sold out.

 

[Richard Hed]

A while ago I saw lead free Sn63Pb37 solder paste on one of usual suspect Chinese selling websites . Easier to work with.
No problems with the vegan neighbour and no problems with the process, but it seems to be sold out.

Oh yes, that's good, that's really good. It's like since I am Jewish, I want kosher. since I live in the Philippines a good part of the year I need to get Kosher bacon. Of course all the shops and restaurants have Kosher bacon. It's the only place in the world I can get it.

 

[Steamchick]

I can't stand this modern Lead free stuff either ! and If you want REALLY good joints try Tin/Lead/Silver it's a bit pricey but it's absolutely beautiful to work with.

More H&S gone mad, we've been using Tin/Lead solders for well over 100 years and Lead water pipes since the Romans, but the whole world hasn't been struck down with Lead poisoning

Best Regards Mark

Hi Mark,
Please listen carefully. Lead pipes do dissolve into the water you drink. Only very slightly in hard water areas, but more so in soft water areas. Lead in the body migrates to the brain - I think - but maybe I can't remember so well? I.E. - It leads (excuse the pun) to dementure, and other brain degenerative diseases.
My Sister did her Doctorate on the pollution of lead and how it affects PRIMARY and SECONDARY school kids. Much younger than us? Those with lead from water and air sources had on average 3% lower IQ.... by the time they were 16. OK. That's statistics, just measurable you may say? We all get a little bit of lead in our lifetime. But a lot does NOT do you any good. And you never get rid of it while alive...
Maybe it is not as poisonous as smoking, in the quantities we normally experience, and we don't care if we reach the biblical "3 score years and 10" - or "101 and Out!" cricket score. But lead-induced dementure can spoil the final decade.... for your loved ones at least.
Of course, "High velocity Lead poisoning" can induce an earlier demise... so please avoid guns as well.
And life expectancy for the average Roman man was 40 years.... Not even Biblical!
K2

 

[Richard Hed]

Hi Mark,
Please listen carefully. Lead pipes do dissolve into the water you drink. Only very slightly in hard water areas, but more so in soft water areas. Lead in the body migrates to the brain - I think - but maybe I can't remember so well? I.E. - It leads (excuse the pun) to dementure, and other brain degenerative diseases.
My Sister did her Doctorate on the pollution of lead and how it affects PRIMARY and SECONDARY school kids. Much younger than us? Those with lead from water and air sources had on average 3% lower IQ.... by the time they were 16. OK. That's statistics, just measurable you may say? We all get a little bit of lead in our lifetime. But a lot does NOT do you any good. And you never get rid of it while alive...
Maybe it is not as poisonous as smoking, in the quantities we normally experience, and we don't care if we reach the biblical "3 score years and 10" - or "101 and Out!" cricket score. But lead-induced dementure can spoil the final decade.... for your loved ones at least.
Of course, "High velocity Lead poisoning" can induce an earlier demise... so please avoid guns as well.
And life expectancy for the average Roman man was 40 years.... Not even Biblical!
K2

Ah, but lead does leave the body very slowly thru hair and nail growth. There is also a treatment that very few people know about. It is a technique developed for Hanford workers who get heavy metals in their bods. They tested hair of Beethoven and found that indeed, he had lead poisoning. They thimpfk he drank the water at one of the baths (bad or baden) in Deutchland.

 

[Steamchick]

Thanks Richard, Not being one of the few, I didn't know about that.
Being in the Motor industry for more than half my career - the part when legislation banned lead and lots of other things - I have learned that Governments only ban things when it costs them more not to do so. As long as only a very small percentages of people in the UK use motorcycles, then they won't be banned. If they stopped the tax on cigarettes they would have to ban them! But deleting lead from road fuel meant their tax revenue went up by between 5 and 10%... so that was a good idea! Digging coal would have cost a fortune in death compensation from lung diseases, so they banned most of it before that happened, and the poor Beggars died without a penny for it!
C'est la Guerre... Pass me a light for a *** and I'll go for a blast on the Motorbike while I still can!
K2

 

[Richard Hed]

Thanks Richard, Not being one of the few, I didn't know about that.
Being in the Motor industry for more than half my career - the part when legislation banned lead and lots of other things - I have learned that Governments only ban things when it costs them more not to do so. As long as only a very small percentages of people in the UK use motorcycles, then they won't be banned. If they stopped the tax on cigarettes they would have to ban them! But deleting lead from road fuel meant their tax revenue went up by between 5 and 10%... so that was a good idea! Digging coal would have cost a fortune in death compensation from lung diseases, so they banned most of it before that happened, and the poor Beggars died without a penny for it!
C'est la Guerre... Pass me a light for a *** and I'll go for a blast on the Motorbike while I still can!
K2

Yeah, well, I have had about 5 cigarettes in the last 10 weeks and every time I see someone smoking in a tv show or on the street, I want a ***. My daughter's motorbike is too difficult to ride and I doesn't have the $$ to buy a new one. Well, as far as the government goes, ask anyone on the street if they trust their government. However, sometimes government actually does something right and I believe that the environmental work they didded in the '70s and later is a goo thing. I hitchhiked out to the wild east in the USA in 1969--the rivers were filthy white with poisons and pollution, Boston was so thick with oil droplets hanging in the air, one could see the stuff a mere 5 feet away. My lungs burnt, my eyes burnt, headache--I spent ONE weekend there and left. Since 1972 when Nixon passt the EPA laws, things were rightly cleaned up. ONe can now swim in the rivers and breathe in the large cities. There are lots of things that were banned and cleaned up. Unfortunately, sometimes those things might need to be UNdone.

Heavy metal detoxification is called Chelation. I had it done, two treatments. There is also some over the counter stuff, don't know if it helps. By my photo, you can tell the treatment workt.

 

[Steamchick]

I still enjoy Heavy Metal... loud drums and guitar. Bring it on! I don't need the detoxification (Yet).But it does damage hearing. As does wind noise on the bike ...
K2

 

[Richard Hed]

I still enjoy Heavy Metal... loud drums and guitar. Bring it on! I don't need the detoxification (Yet).But it does damage hearing. As does wind noise on the bike ...
K2

Yes, I asked some bikers once, if the loudness hurt their hearing. They wore earplugs--thumbs up on that. I absolutely detest heavy metal as nuthing more than noise. I call it screamer music for neglected children.

 

[skyline1]

Please listen carefully. Lead pipes do dissolve into the water you drink. Only very slightly in hard water areas, but more so in soft water areas. Lead in the body migrates to the brain - I think - but maybe I can't remember so well? I.E. - It leads (excuse the pun) to dementure, and other brain degenerative diseases.
My Sister did her Doctorate on the pollution of lead and how it affects PRIMARY and SECONDARY school kids. Much younger than us? Those with lead from water and air sources had on average 3% lower IQ.... by the time they were 16. OK. That's statistics, just measurable you may say? We all get a little bit of lead in our lifetime. But a lot does NOT do you any good. And you never get rid of it while alive...
Maybe it is not as poisonous as smoking, in the quantities we normally experience, and we don't care if we reach the biblical "3 score years and 10" - or "101 and Out!" cricket score. But lead-induced dementure can spoil the final decade.... for your loved ones at least.
Of course, "High velocity Lead poisoning" can induce an earlier demise... so please avoid guns as well.

I totally agree with this and there is no doubt that lead is dangerous especially in large doses. But the amounts ingested through soldering (even a lifetime of it) are very small compared to other sources. It can be mitigated by the fume extraction that high volume soldering companies use, (right at the soldering iron tip usually).

(Warning minor rant coming)

So a blanket ban (At least commercially) is, in my opinion, pretty excessive. It is typical of the "petty dictats" that western manufacturing now has to put up with. It is small wonder that only China and India are becoming the world's manufacturing hubs, apart from the obvious low labour costs, they do not have the mountains of bureaucratic "red tape" to put up with.

(Rant over You can remove your tin hats now chaps)

As a Sound Technician as well as an Engineer I've probably got "Led Zep poisoning" as well

I absolutely detest heavy metal as nuthing more than noise. I call it screamer music for neglected children.

Some of this extreme "Thrash Metal" actually is ! On a spectrum analyser it looks just like the broadband noise Sound Engineers use to set up the rig. with bursts of distorted vocal on top. I hate doing those Gigs.

Best Regards Mark

 

[Richard Hed]

I totally agree with this and there is no doubt that lead is dangerous especially in large doses. But the amounts ingested through soldering (even a lifetime of it) are very small compared to other sources. It can be mitigated by the fume extraction that high volume soldering companies use, (right at the soldering iron tip usually).

(Warning minor rant coming)

So a blanket ban (At least commercially) is, in my opinion, pretty excessive. It is typical of the "petty dictats" that western manufacturing now has to put up with. It is small wonder that only China and India are becoming the world's manufacturing hubs, apart from the obvious low labour costs, they do not have the mountains of bureaucratic "red tape" to put up with.

(Rant over You can remove your tin hats now chaps)

As a Sound Technician as well as an Engineer I've probably got "Led Zep poisoning" as well



Some of this extreme "Thrash Metal" actually is ! On a spectrum analyser it looks just like the broadband noise Sound Engineers use to set up the rig. with bursts of distorted vocal on top. I hate doing those Gigs.

Best Regards Mark

I've actually heard one or two heavy metals that were good, however. Also, someone defending it said there are two types: one for neglected children and one that is better. BTW, I use a "lead foil hat"--it works better.

 

[Steamchick]

Richard, It isn't the bikes that make one deaf, it is the wind noise in the helmets.... And usually it is only the "modern" riders who wear ear plugs. When the ear bones are worn with big gaps, it stops hurting. - What did you say? I can't hear over 8KHz... I can't hear soft sounds any more? - Sorry, I missed that?
And the constant whistle (like the TV used to make after midnight) is only there while I am awake... But at speed on the bike the wind noise drowns it out! Why is there a Government limit of 92dB at 70 mph for helmets? For a 6 hour ride it should be below 78dB! ear plugs may knock-off 1~3dB... And in the 70s, with very good helmets of that era, I could easily do 4 or more hours at the speed limit and not hear for 2 or 3 days afterwards...
Nuff sed.
K2