Why some new members will do better than others here.

[waksupi]

Edited to ADD: By the way if booze and water don't separate how do you make Apple Jack on a cold night in the northern US?

By allowing the hard cider to freeze partially. Water freezes at a higher temp than an alcohol solution so the first ice to form is largely water. This means removing the first bits of ice removes mostly water giving a higher alcohol content.

This is NOT gravity separation of a solution, it is removing something from the mix be freezing. Totally different.

Gravity separation of a molten, fully liquid, lead alloy at temps we use does not happen.

Isn't that backwards? I thought the alcohol thawed first. Otherwise, why do I pour Heet in my gas tank in the winter?

[Sweetpea]

Ric, you're both right...

The water freezes first, as the temperature is dropping.

The alcohol thaws first, as the temperature is rising.

[GhostHawk]

BTROJ is correct, the freezing tends to push the alcohol and sugars into the center.

2 liter pepsi/coke bottles work great for this, fill them to the shoulder and let them age on your back porch while waiting for cold weather.

Wake up to a -20 morning, grab a strainer, a big bowl and empty what will run out of the 2 liters.

GOOOOOOOOOOOOOD stuff that packs a punch!

Be it apple jack or Wild Plum.
I call it "Freeze Brandy"

Lead however won't separate no matter how cold it gets. And I've known a few guys that thought it would gravity separate when melted, but never could prove it.

[9.3X62AL]

yeah but Rick what aout me gravity separating the boolit from the case oooh noo wait ....
ha ha

I generally use primer and powder for this activity, myself. And a firearm. But that's just me, and I've been called 'lacking in imagination' from time to time.

[blackthorn]

Ahhh yes---BUT---there have been threads on this forum about zinc contaminated alloy being "saved" by taking the cold metal, and bringing it to liquidus slowly, which is supposed to result in the formation of an "oatmeal" like layer (zinc) forming on top of the melt. This layer is then skimmed from the top of the alloy (allegedly) removing zinc from the melt! True or not?? If it is true and this method works would that not be "gravity" separation?? I do recognize that if the temperature continues to be increased the zinc would reintegrate into the alloy, especially if the melt is fluxed.

[btroj]

No, that is separation based upon melt point. It is actually very similar to the apple jack mentioned earlier. By manipulating temps we can "freeze" out a substance based upon melt point differences.

We are speaking of gravity separation of a fully liquid pot 'o lead.

[GoodOlBoy]

No, cbrick, I have never had a job making magic wands. Being a Christian that would be out of my wheel house. Want to know why some members won't last? Because when they try to have a discussion you always have some joker who wants to throw in repeated BS comments that have nothing to do with the situation. If what you are looking for is magic, I would suggest you go rent a copy of harry potter and let those interested in scientific debate have an adult conversation. Thanks.

Any give element or compound floats because of buoyancy. Buoyancy does not work in zero gravity environments. Why?

For this reason, an object whose density is greater than that of the fluid in which it is submerged tends to sink. If the object is either less dense than the liquid or is shaped appropriately (as in a boat), the force can keep the object afloat. This can occur only in a reference frame which either has a gravitational field or is accelerating due to a force other than gravity defining a "downward" direction (that is, a non-inertial reference frame). In a situation of fluid statics, the net upward buoyancy force is equal to the magnitude of the weight of fluid displaced by the body.

It is very simple physics. You can say "Oh it's not gravity it's oxidation!" Why does oxidation float? Oxidation is defined as

the interaction between oxygen molecules and other substances

. Once oxygen is bound to another molecule the molecule because lighter (assuming it is heavier than oxygen to being with) and begins to float. Why does oxidation float? Because of buoyancy. How does buoyancy work? Gravity. How about "Oh no it just does that once it is fluxed!" Why is that? Because flux either binds to the element and causes buoyancy, OR it causes another element to be formed (such as carbon or oxygen) which binds to the element and again causes buoyancy.

By the way scuba divers are very familiar with gravity, buoyancy, and the effects of micro g or zero g environments. Some time look at a website for divers and look up the topic "How to achieve neutral buoyancy at various atmospheres of depth."

Sorry but it's science not magic.

Believe it, or don't.

GoodOlBoy

[cbrick]

No not BS, you have been told several times already that a lead alloy cannot gravity separate. Not because it's a joke but because it's a fact. You quote an 1897 article but do you suppose that it's possible the metals industry may have learned something since then?

Oxidation only happens on the surface of the melt where the alloy is in contact with oxygen. Scuba divers have nothing whatever in common with molten lead alloys. Nothing.

Read chapter 4 in this link and perhaps you'll see where your confusing two things that are very dissimilar, oxidation and gravity separation. I recommend the whole book but chapter 4 is on fluxing and covers how and why.

http://www.lasc.us/Fryxell_Book_textonly2.pdf

Rick

[GoodOlBoy]

Now THAT reply was not BS cbrick. But suggesting magic wands?

So because I have been told multiple times, by people I don't know from adam, a thing is a fact I should accept it? No thanks.

Is the world still flat? Does lunchmeat still create maggots? Heck now science cannot agree on what the half life of some radioactive materials are and some believe that carbon dating may be off as much as millions of years.

Here's what I do know from metallurgy we as a society cannot recreate many of the processes used by blacksmiths throughout history to create iron and steel in forms that match what was made even 150 years ago. Sometimes look up the difference in irons made by blacksmiths in colonial America that had a fibrous nature to them when bent to the breaking point, and modern irons which don't. Or look up the ancient African iron men who could retrieve iron from red sand which modern foundries can't do.

So what does that have to do with the conversation? If a person smelting lead in 1891 believed that gravity was only a portion (but still a portion) of the equation does it automatically make that person wrong that their information was 200+ years old? Are we still using lead ore that's older than that book, or has all the newly mined lead ore started following different rules because time passed?

I read through the link you posted (thanks for that by the way saved a copy) and nothing in the link says that oxidation doesn't float because of the effects of gravity. Therefore if oxidation floats, floating is a direct effect of gravity, and we use oxidation to separate alloys we ARE using a form of gravity separation. All we are doing by oxidizing, fluxing, binding, or separating is removing bonds from one atom to another so that the lighter item can float or a heavier item can sink. And yet again nothing can float or sink without ..... gravity.....

Thanks for the conversation.

GoodOlBoy

[btroj]

Wow. The scientific base of the board is sinking fast.
The entire metals industry is so dumb. They keep adding chemicals to slurries of crushed ore to help concentrate the desirable mineral. They should just let gravity do the work.

The ability of a mineral to float depends upon its surface properties. Chemical modification of these properties enables the mineral particles to attach to an air bubble in the flotation cell. The air bubble and mineral particle rise through the pulp to the surface of the froth or foam that is present on the flotation cell. Even though the air bubbles often break at this point, the mineral remains on the surface of the froth. The mineral is physically separated from the remaining pulp material and is removed for further processing.


That is a quote from a website for Chevron Phillips for the floatation chemicals they produce for the ore refining industry. They mention flotation but not gravity. Hmmmmm

Here is what Merriam-Webster says about flotation.

Full Definition of FLOTATION


1
: the act, process, or state of floating
2
: an act or instance of financing (as an issue of stock)
3
: the separation of the particles of a mass of pulverized ore according to their relative capacity for floating on a given liquid; also : any of various similar processes involving the relative capacity of materials for floating
4
: the ability (as of a tire or snowshoes) to stay on the surface of soft ground or snow

No mention of gravity?

How about buoyancy?

Full Definition of BUOYANCY


1
a : the tendency of a body to float or to rise when submerged in a fluid
b : the power of a fluid to exert an upward force on a body placed in it; also : the upward force exerted
2
: the ability to recover quickly from depression or discouragement : resilience
3
: the property of maintaining a satisfactorily high level (as of prices or economic activity)


Based on your understanding of science relating to gravity a boat defies gravity. It should sink, it is made of a material heavier than water.

Wait, Archimedes long ago figured that out. The boat floats because the weight of the water displaced weighs more than the boat itself. That is what determines buoyancy and whether it not it will float. Notice it speaks of weights, not mass? The use of weight signifies that gravitational pull is included as weight is a unit of force, mass is not.

If I fall from a cliff I wasn't gravity separated from the cliff, I fell. I was never mixed into the cliff, I was never alloyed with it. Being that I wasn't part of the cliff I couldn't be separated from it.

[GoodOlBoy]

Now you are arguing displacement vs flotation. I agree boats float because of displacement relative to the weight of the boat in question and the sectional density of the water it is on. IE salt vs fresh water displacement is different, however, most boats will float on both.

You can post definitions from sites if you wish, and I have done it as well. But for a really good discussion on gravity, sinking, and floating? http://www.physicsforums.com/showthread.php?t=178483

But if you fall from a cliff you are acted upon by gravity are you not?

If a piece breaks off the cliff does it fall, float, or hover? I would assume it falls due to gravity, and that piece WAS a part of the cliff.

By the way the repeated argument of "Then why doesn't industry know to use gravity separation?"

Gravity separation is an industrial method of separating two components, either a suspension, or dry granular mixture where separating the components with gravity is sufficiently practical: i.e. the components of the mixture have different specific weight. All of the gravitational methods are common in the sense that they all use gravity as the dominant force. Gravity separation is used in a wide variety of industries, and can be most simply differentiated by the characteristics of the mixture to be separated - principally that of 'wet' i.e. - a suspension versus 'dry' -a mixture of granular product. Often other methods are applied to make the separation faster and more efficient, such as flocculation, coagulation and suction. The most notable advantages of the gravitational methods are their cost effectiveness and in some cases excellent reduction. Gravity separation is an attractive unit operation as it generally has low capital and operating costs, uses few of any chemicals that might cause environmental concerns and the recent development of new equipment enhances the range of separations possible.

Seems to me the industry DOES know about it.

GoodOlBoy

[btroj]

Think of it this way. Gravity is a force, no more, no less. As a force it pull on everything in our lives. It gives us weight. It drives many things. We over come it to fly. It causes convection currents due to warmer air having less weight, hence it rises.

The fact that these things may not occur in space is hardly relevant to this discussion. I have no plans to cast bullets on the ISS so what might happen there isn't something I'm concerned about.

We are speaking of how gravity acts on a molten pot of lead. I'm concerned only with the liquid phase, not any solids. The liquid phase will not gravity separate, period. Can I induce chemical or physical changes to the liquid allowing me to separate things out? Absolutely. I can alter the temp or cause oxidation to occur but those are chemical and physical changes that ALLOW gravity to act differently upon some portions of the melt than on others. Gravity alone did not cause the separation, some other physical or chemical process played a larger role which allowed gravity to act differently based on differences in densities of the item precipitated out.

[btroj]

Wow. The scientific base of the board is sinking fast.
The entire metals industry is so dumb. They keep adding chemicals to slurries of crushed ore to help concentrate the desirable mineral. They should just let gravity do the work.

The ability of a mineral to float depends upon its surface properties. Chemical modification of these properties enables the mineral particles to attach to an air bubble in the flotation cell. The air bubble and mineral particle rise through the pulp to the surface of the froth or foam that is present on the flotation cell. Even though the air bubbles often break at this point, the mineral remains on the surface of the froth. The mineral is physically separated from the remaining pulp material and is removed for further processing.


That is a quote from a website for Chevron Phillips for the floatation chemicals they produce for the ore refining industry. They mention flotation but not gravity. Hmmmmm

Here is what Merriam-Webster says about flotation.

Full Definition of FLOTATION


1
: the act, process, or state of floating
2
: an act or instance of financing (as an issue of stock)
3
: the separation of the particles of a mass of pulverized ore according to their relative capacity for floating on a given liquid; also : any of various similar processes involving the relative capacity of materials for floating
4
: the ability (as of a tire or snowshoes) to stay on the surface of soft ground or snow

No mention of gravity?

How about buoyancy?

Full Definition of BUOYANCY


1
a : the tendency of a body to float or to rise when submerged in a fluid
b : the power of a fluid to exert an upward force on a body placed in it; also : the upward force exerted
2
: the ability to recover quickly from depression or discouragement : resilience
3
: the property of maintaining a satisfactorily high level (as of prices or economic activity)


Based on your understanding of science relating to gravity a boat defies gravity. It should sink, it is made of a material heavier than water.

Wait, Archimedes long ago figured that out. The boat floats because the weight of the water displaced weighs more than the boat itself. That is what determines buoyancy and whether it not it will float. Notice it speaks of weights, not mass? The use of weight signifies that gravitational pull is included as weight is a unit of force, mass is not.

If I fall from a cliff I wasn't gravity separated from the cliff, I fell. I was never mixed into the cliff, I was never alloyed with it. Being that I wasn't part of the cliff I couldn't be separated from it.

[GoodOlBoy]

I agree 100%. My sole reason for arguing the point was that there seemed to be some underlying opinion that gravity had nothing to do with separation, when in point of fact it does. While it is not (as you have said, and as I have posted quotes agreeing with you) the MAJOR factor in separation it is A factor. Did gravity cause the separation? No. Could the separation have happened without gravity. Yes. Could the separated material float or sink without gravity? No.

So by saying that you cannot use gravity to separate lead alloy that has been heated and "fluxed" is incorrect because without gravity to cause the material to float or sink you would have a suspension, not a separation. But as a counter you cannot set a block of lead on the counter and watch the alloy separate just from gravity. Which I also stated earlier.

Heck I enjoyed the conversation.

GoodOlBoy

[GoodOlBoy]

Ok I had to go back and reread because I thought posts had suddenly been deleted. It appears to me, I could be wrong, that for some reason the timestamps are not quite right and the lasts few posts seem to be out of order to me now. Otherwise how did I respond to displacement BEFORE btroj mentioned it?

Weird

BTW how did gravity separation become the topic in a thread about how some new member's won't last?

GoodOlBoy

[Sweetpea]

When I'm casting, as long as gravity is keeping the alloy in the pot, that's good enough for me...

[Aunegl]

Wow. The scientific base of the board is sinking fast.
The entire metals industry is so dumb. They keep adding chemicals to slurries of crushed ore to help concentrate the desirable mineral. They should just let gravity do the work.

The ability of a mineral to float depends upon its surface properties. Chemical modification of these properties enables the mineral particles to attach to an air bubble in the flotation cell. The air bubble and mineral particle rise through the pulp to the surface of the froth or foam that is present on the flotation cell. Even though the air bubbles often break at this point, the mineral remains on the surface of the froth. The mineral is physically separated from the remaining pulp material and is removed for further processing.


That is a quote from a website for Chevron Phillips for the floatation chemicals they produce for the ore refining industry. They mention flotation but not gravity. Hmmmmm

Here is what Merriam-Webster says about flotation.

Full Definition of FLOTATION


1
: the act, process, or state of floating
2
: an act or instance of financing (as an issue of stock)
3
: the separation of the particles of a mass of pulverized ore according to their relative capacity for floating on a given liquid; also : any of various similar processes involving the relative capacity of materials for floating
4
: the ability (as of a tire or snowshoes) to stay on the surface of soft ground or snow

Brought back some memories when I worked in the Inspiration Copper mine in Claypool, AZ. The reagents had a distinct smell when the flotation machines were running, in the concentrator building.

[olafhardt]

You often can only dissolve only a small amount of solute in a certain amount of solvent. Spoon sugar into your coffee. After a while it sinks and stays sunk regardless of how much you stir it. Heat it up a little and more sugar dissolves, cool it off and sugar crystallizes out. Only a little zinc is soluble in lead. Have more and the excess zinc floats on the lead. At less than the solubility limit the zinc won't float out. Expose the homogeneous alloy below the solubility limit to oxygen and the zinc forms zinc oxide which floats. Lead oxide can form and be reduced back to lead by the zinc still dissolved in the alloy. I have been on and off this thread from early on. In my opinion the first part was pretty much an uncharitable put down of people seeking information and the last several posts have been long winded quibllling.containing bad information. Moderators you have not done your job. This post should never have been stickied and should have been closed long ago. Unstick it throw it in the trash and we can all work on restoring our past high standards.

[Bodean74]

Heck I read as much as I could on this site for about 9 months before I even joined.

Same here... Its hard to ask a Question when The more I read the more answers I find thank you guys...three years young to the game.

[joelsteinbach]

I should have read this first before I started to ask questions that have been answered 100 times before, After discovering the search feature of this site, I feel that most of my questions can easily be answered with a little work on my part.