How To Make a Smelter

[[email protected]]

To All:

It's easy. YOU CAN DO IT.

The basic idea is to line a steel drum or barrel with refractory
material such as fire brick, mortared together with fire-clay, sand
and refractory cement. That will get you a BIG smelter, one you'll
probably NEVER USE.

So start with a SMALLER steel drum. Get yourself a 'boat' --
something in which to mix your refractory CEMENT. You aren't going to
use any fire brick... except mebbe for the bottom.

You want the bottom to be about two inches thick and solid refractory
material. Pumping up a good flame, the temperature will approach
three thousand degrees Fahrenheit. And that is one hell of a fire,
pard.

Get yourself some CARDBOARD. Quite a bit of it. You are going to
ROLL the cardboard until it has the OD that you want. The OD must
match the OD of your CRUCIBLE plus about two inches per side. So go
find yourself a crucible. But keep in mind, if you're smelting
aluminum you DON'T want it in contact with any iron or steel. It will
be 'poisoned' and turn out brittle (!) (Yeah, I didn't think so
either. Trust me, it'll crack like glass.) Now you CAN use iron or
steel... so long as you DIP your crucible in a refractory COATING
before you charge it with lumps of aluminum. Just mix up the
refractory coating about the same as pan-cake mix, then dip the pot in
it, let it drain, then dry, the BAKE to cure it. All cured? Then dip
it again. In fact, dip it about three times. Last time is the
charmer. Make sure it has no cracks and that you haven't scraped
through the dip at any point. Now you can bake it. Pretend it's just
another piece of ceramic art. It won't be, because you'll have a
couple of tangs stick out through it which you have CLEANED OFF every
time you've dipped it. Then put it in the furnace to bake. Patience
is your pal. Go do something else whilst baking your refractory mix.

What's a good mix? I used fire-clay and a patent 'refractory cement'
-- some black sh.... stuff that you mix with water. I added fire-clay
to that and ended up with a thick, grey slurry. I dipped and let it
air-dry twice, then threw some charcoal into the furnace, light it
off, got the charcoal going good then propped the crucible over the
coals. I didn't pay a lot of attention to the inside of the
crucible. It was a solid, seamless coating. I made the pot out of
steel tubing 4.5" in diameter and about 9" high. The bottom was a
piece of 3/8" thick steel plate, MIG'ged to the pipe. I cut a couple
of bolts down to 1" length measured from under the head. I made two
sets of tongs, one to lift the crucible in & out of the furnace (lid
is off, the thing will flat FRY you unless you are protected by at
least two layers of leather... and more is better). Furnace has a 2"
hole in the side down low; lid has a 2" hole in the middle (was a tin
can until I poured in the refractory stuff, mixed with lotsa fire-clay
and #80 silicon sand.

You see some guys using tongs six feet long and you laugh. Don't.
Not until you've had a pot full of molten metal in your grip.

You got goodd shoes? And I'm not talking K-Mart. Good LEATHER
shoes. Plus leather OVER them to act like a rain shield, in case you
slip and spill a little.

Once you pull the pot out of the furnance you'd damn well better know
what comes next... you can't stand there hold it with one hand while
scratching your ass, trying to figure out what to do.

Mine, I gotta sit it down. So I have a Sitting Down Place.
Concrete. Dry. Pouring Tongs just beside it. Sit down the crucible,
pick up the Pouring Tongs, pick up the crucible, move mebbe six
inches... prolly less, there's the flask, ready & waiting. Pour.

Hell of a note.. Steam. Smoke. Fumes. Flames. You're inside of it
all, standing there, pouring. Nice & steady. Pouring. That's your
job. Pour the molten metal outta the pot into the flask. Pouring.
At just the right speed. Fill it right up. Fill up the mold and the
tower and the top of the flask. And you'd better have made damn sure
you got enough metal to fill the mold.

All done? Okay, swing the crucible over HERE and pour any excess into
those ingot molds. Shouldn't have any excess but some is better than
none. Now swing the crucible BACK to the Sitting Down Place. Sit it
down. Put down the Pouring Tongs, pick up the Lifting Tongs, put the
crucible back into the furnace. Close the lid. Now you can think
about other things.

Lemme give you a hint. If you've never cast nothing in your life
before, DON'T start with this. Start by casting some fish weights
outta wheel balance weights. Start with casting balls for your cap &
ball rifle. Start with anything OTHER than a bucket fulla aluminum.
Because there's a lot of little details that can scar you for life.
And you only get the one chance to learn... that FIRST time. It helps
if you got someone there who'se done it before, kinda breathing down
your neck.

FIRST time, do something EASY. Rudder pedals. "VP-II" cast right
into them suckers!

-R.S.Hoover

[Stealth Pilot[_2_]]

On Sun, 25 Jan 2009 18:36:27 -0800 (PST), "
> wrote:

>To All:
>
>It's easy. YOU CAN DO IT.
>
>The basic idea is to line a steel drum or barrel with refractory
>material such as fire brick, mortared together with fire-clay, sand
>and refractory cement. That will get you a BIG smelter, one you'll
>probably NEVER USE.
>
>So start with a SMALLER steel drum. Get yourself a 'boat' --
>something in which to mix your refractory CEMENT. You aren't going to
>use any fire brick... except mebbe for the bottom.

<snip>

>All done? Okay, swing the crucible over HERE and pour any excess into
>those ingot molds. Shouldn't have any excess but some is better than
>none. Now swing the crucible BACK to the Sitting Down Place. Sit it
>down. Put down the Pouring Tongs, pick up the Lifting Tongs, put the
>crucible back into the furnace. Close the lid. Now you can think
>about other things.
>
>Lemme give you a hint. If you've never cast nothing in your life
>before, DON'T start with this. Start by casting some fish weights
>outta wheel balance weights. Start with casting balls for your cap &
>ball rifle. Start with anything OTHER than a bucket fulla aluminum.
>Because there's a lot of little details that can scar you for life.
>And you only get the one chance to learn... that FIRST time. It helps
>if you got someone there who'se done it before, kinda breathing down
>your neck.
>
>FIRST time, do something EASY. Rudder pedals. "VP-II" cast right
>into them suckers!
>
>-R.S.Hoover

two points, I'm not even going to touch on burners.

B. Terry Aspin wrote a book on home foundry work. it is available
through the Model Engineer sources in England. Very good reference for
someone thinking about this.
a suggestion that terry made in model engineer that has saved my
bacon.
eventually you will break a crucible. they come out of the furnace
between white hot and very cherry red depending on what you are
melting. they are in the plastic range for strength and when one goes
it often goes slowly just with an inexorable tearing.

for just these moments you need a few of terry's sand trays. at least
one every pour.
they are done in galv sheet steel and are about 18" square. you bend
up about 2" around each side to about 45 degrees and braze the
corners. into your emergency tray goes the driest of driest sands to
about an inch or so depth. in the sand you make swirl marks with your
fingers.

when you have the realisation that a crucible is letting go you place
it in the sand tray, or you pour it out in the sand tray.
that tray is the only dry safe place that you can dump the molten
metal.
if you drop it onto the ground any moisture that is present will flash
to steam instantly and explode the molten metal into a hand grenade.

I use a salamander crucible usually. In australia they also make a
fireclay crucible that is a single use item in the gold assay
industry. they are just a couple of dollars - cheap as chips. I have
used one for 18 months on a regular basis doing aluminium castings.
when one of these guys gets damaged and starts to come apart Terry's
sand trays are worth gold.

hydrogen embrittlement was a big bogey man in home castings but it is
easily understood and conquered.
just as salts dissociate in water to become their component ions water
itself seems to do the same sort of thing in aluminium. the hydrogen
can be absorbed by the molten aluminium in amazing quantities, the
oxygen becoming oxide dross on the surface of the mix.
cooled solid aluminium has no ability to hold hydrogen and it comes
out of solution in bubbles through the metal.

the ways to conquer this: make sure all the metal you melt is bone
dry. cast on low humidity days. if you notice lots of dross coming to
the surface you should purge the mix with an aluminium chloride tablet
plunged to the base of the crucible in a stainless steel wire cage.
this also dissociates in the molten metal and the aluminuim joins the
pour. the chlorine bubbles up combining with the hydrogen to vent off
as hydrogen chloride gas. if you get a wiff of this it is unbelievably
pungent and combines with moisture in your nose etc to become
hydrochloric acid. it does however do an incredibly good job of
purging the hydrogen gas from the mix.

ok two points done.

this one is a freebie. if you find that you need to make a metal mould
to get the fine fin detail, a cheap as chips mould release is as close
as a wax candle. light the candle and play the flame over the inside
of the metal mould and coat it all in soot. I've only used small metal
molds for model engines but I've never had the aluminium ever get
through the soot release to bond with the mold.
I'm sure veedubber will appreciate the sheer economy of that tip.

Stealth pilot

[Karl-Heinz Künzel]

Those two:

Foundrywork for the Amateur
B.Terry Aspin
WORKSHOP PRACTICE SERIES 4
Argus Books 1984
ISBN 0 85242 842 1

The Charcoal Foundry
David. J. Gingery
ISBN 1 878087 002


KH

[Karl-Heinz Künzel]

Karl-Heinz Künzel schrieb:
> Those two:
>
> Foundrywork for the Amateur
> B.Terry Aspin
> WORKSHOP PRACTICE SERIES 4
> Argus Books 1984
> ISBN 0 85242 842 1
>
> The Charcoal Foundry
> David. J. Gingery
> ISBN 1 878087 002
>
>
> KH

Maybe a 3.rd one

The complete handbook of sand casting
A do-it-yourself guide to forming all types of metal in versatile sand
molds.

C.W.Ammen
TAB BOOKS
ISBN 0 8306 9841 8

That author also published

- The Metalcaster's Bible

- Casting Brass

- Casting Aluminum

KH

[Stealth Pilot[_2_]]

On Mon, 26 Jan 2009 14:25:43 +0100, Karl-Heinz Künzel
> wrote:

>Karl-Heinz Künzel schrieb:
>> Those two:
>>
>> Foundrywork for the Amateur
>> B.Terry Aspin
>> WORKSHOP PRACTICE SERIES 4
>> Argus Books 1984
>> ISBN 0 85242 842 1
>>
>> The Charcoal Foundry
>> David. J. Gingery
>> ISBN 1 878087 002
>>
>>
>> KH
>
>Maybe a 3.rd one
>
>The complete handbook of sand casting
>A do-it-yourself guide to forming all types of metal in versatile sand
>molds.
>
>C.W.Ammen
>TAB BOOKS
>ISBN 0 8306 9841 8
>
>That author also published
>
>- The Metalcaster's Bible
>
>- Casting Brass
>
>- Casting Aluminum
>
>KH

aspin and ammen are the good ones.

[[email protected]]

On Jan 27, 12:39*am, Stealth Pilot >
wrote:

> aspin and ammen are the good ones.
-----------------------------------------------------------------------------------------------------------
Roger that. But if you Google Aspin you'll find it available (via
Amazon) in Japan, France and the UK... but not in the USA. :-)

-Bob

PS -- Big Day for the Doc Shop today. (I surely wish they'd warm
up them IV's. Definitely a chilling experience.

[flash]

You guys ! You make my hair ache and my teeth itch ! Or, alternately, you
make my conscience burn me a little, at least, which is maybe not a bad
thing, for failing to come to know and understand more about the process.

For 13 years, I worked in a machine shop that had a significantly large iron
foundry attached, and I paid a bit of attention then. But now, I wish I
had spent LOTS more time and interest on the means, methods and materials.
Such knowledge as I did absorb was of the simply marvelous.

The guys who do this day in and day out are artists handling 2500-degree
molten iron ("liquid death").

Woh'da thunk that you could cast iron in an iron mold? More ways to ram
sand, more different kinds of sand, all kinds of patterns . . . . well, they
spent their lifetimes learning all that stuff. That, and more besides.

Flash



> wrote in message
...
On Jan 27, 12:39 am, Stealth Pilot >
wrote:

> aspin and ammen are the good ones.
-----------------------------------------------------------------------------------------------------------
Roger that. But if you Google Aspin you'll find it available (via
Amazon) in Japan, France and the UK... but not in the USA. :-)

-Bob

PS -- Big Day for the Doc Shop today. (I surely wish they'd warm
up them IV's. Definitely a chilling experience.

[Brian Whatcott]

Stealth Pilot wrote:
.....
> when you have the realisation that a crucible is letting go, you place
> it in the sand tray, or you pour it out in the sand tray.
> that tray is the only dry safe place that you can dump the molten
> metal....
> Stealth pilot

You might think that a puddle of lead on the concrete garage floor could
hardly do much harm. After a concrete chip whistles past your ear, you
think again.

Brian W

[Morgans[_2_]]

"Stealth Pilot" > wrote

> hydrogen embrittlement was a big bogey man in home castings but it is
> easily understood and conquered.

OK, I understand hydrogen embrittlement is a "bad thing" but my question
is, where does it come from, start, or what do you do to prevent it from
happening in the first place. I did like your hints for dealing with it,
and can definitely relate on the hydrochloric acid in the nose bit. Also to
be considered one of the "bad things." <g>
--
Jim in NC

[[email protected]]

On Jan 27, 2:47*pm, "Morgans" > wrote:
> "Stealth Pilot" > wrote

>*but my question
> is, where does it come from, start, or what do you do to prevent it from
> happening in the first place. *I did like your hints for dealing with it,
> Jim in NC

Where does it come from? There is hydrogen all around when casting.
Comes from the propane(butane) burned to make the heat, from that oily
piston tossed into the fire, even the mayo on your hands from lunch.
I suspect those cooking with charcoal actually have less problems than
casters using the "cleaner" fuels.

What to do about it? Clean metal and some degas agent. When I melt
pistons and other salvage I never use it in the virgin state. Cast
some biscuits in your ingot molds and let cool. Then they are ready
to use, and in nice little chunks too :-) Toss in a little salt and
sidewalk de-icer, don't keep peeking at the pot, and you should be
good to go for the real parts.

Works for me. I've never noticed any problems with my castings, but
that doesn't mean there aren't some....................
===================
Leon McAtee

[Fred the Red Shirt]

On Jan 25, 9:36*pm, " > wrote:
> ...
>
> Mine, I gotta sit it down. *So I have a Sitting Down Place.
> Concrete. *Dry. *...
>

I cringed when I read this. Concrete isn't dry. There is always
water retained in the matrix. Heated, it can flash into steam and
explode small chips of concrete and whatever it was that was
hot enough to explode it up into the air.

It is best to use dry sand. If you can, heat it before each use to
make sure it is dry.

And between uses keep it covered as you never know when
a cat is going to come by.

[Maxwell[_2_]]

"Fred the Red Shirt" > wrote in message
...
On Jan 25, 9:36 pm, " > wrote:
> ...
>
> Mine, I gotta sit it down. So I have a Sitting Down Place.
> Concrete. Dry. ...
>

I cringed when I read this. Concrete isn't dry. There is always
water retained in the matrix. Heated, it can flash into steam and
explode small chips of concrete and whatever it was that was
hot enough to explode it up into the air.

It is best to use dry sand. If you can, heat it before each use to
make sure it is dry.

And between uses keep it covered as you never know when
a cat is going to come by.

-----------------------------------------------------------------------------------------------------

You're right about concrete, but with the low melt temp of aluminum, 20 to
30 pounds of aluminum on a floor at least 2 or 3 years or so old is not a
big deal. But concrete 3 to 6 months old, or higher temp metals can be real
exciting.

Sand, because it is loose and permeable, can contain 3 to 5% moisture with
no problems at all. As much a 5% is often used for molding.

[jerry wass]

Maxwell wrote:
> "Fred the Red Shirt" > wrote in message
> ...
> On Jan 25, 9:36 pm, " > wrote:
>> ...
>>
>> Mine, I gotta sit it down. So I have a Sitting Down Place.
>> Concrete. Dry. ...
>>
>
> I cringed when I read this. Concrete isn't dry. There is always
> water retained in the matrix. Heated, it can flash into steam and
> explode small chips of concrete and whatever it was that was
> hot enough to explode it up into the air.
>
> It is best to use dry sand. If you can, heat it before each use to
> make sure it is dry.
>
> And between uses keep it covered as you never know when
> a cat is going to come by.
>
> -----------------------------------------------------------------------------------------------------
>
> You're right about concrete, but with the low melt temp of aluminum, 20 to
> 30 pounds of aluminum on a floor at least 2 or 3 years or so old is not a
> big deal. But concrete 3 to 6 months old, or higher temp metals can be real
> exciting.
>
> Sand, because it is loose and permeable, can contain 3 to 5% moisture with
> no problems at all. As much a 5% is often used for molding.
>
>
>Beg to disagree with you , but concrete which was cured properly ( kept covered

or sprayed with water, so that the water can chemicaly combine with
the materials
in the cement ) has considerable moisture in it known as "water of
hydration."--This bond can be broken with the application of heat.--I
watched an asphalt storage building burn---the melted asphalt would run
out on the floor and burn for a while, until POW! a large piece of the
floor would explode flinging concrete & burning asphalt 10 or 20 ft
away.---the floor was at least 20 years old or so..Poorly cured concrete
still has some water bound up in it, maybe not as much--but it is not as
strong as that which was properly cured.
>
>

[Maxwell[_2_]]

"Jerry Wass" > wrote in message
.. .

>>
>> You're right about concrete, but with the low melt temp of aluminum, 20
>> to 30 pounds of aluminum on a floor at least 2 or 3 years or so old is
>> not a big deal. But concrete 3 to 6 months old, or higher temp metals can
>> be real exciting.
>>
>> Sand, because it is loose and permeable, can contain 3 to 5% moisture
>> with no problems at all. As much a 5% is often used for molding.
>>
>> Beg to disagree with you , but concrete which was cured properly ( kept
>> covered
>
> or sprayed with water, so that the water can chemicaly combine with the
> materials
> in the cement ) has considerable moisture in it known as "water of
> hydration."--This bond can be broken with the application of heat.--I
> watched an asphalt storage building burn---the melted asphalt would run
> out on the floor and burn for a while, until POW! a large piece of the
> floor would explode flinging concrete & burning asphalt 10 or 20 ft
> away.---the floor was at least 20 years old or so..Poorly cured concrete
> still has some water bound up in it, maybe not as much--but it is not as
> strong as that which was properly cured.
>>

I think you misunderstood Jerry, I agreed he was right about the hazard of
heat and concrete. My example was from personal experience. Spilling 200 to
300 cubic inches of 1400 degree aluminum, on a concrete floor more than a
few years old, is not usually a really big deal. Uncontained, it will spread
and quickly cool by 50% in a matter of seconds.

In your example, obviously more than 1400 degrees, with an exposure time of
many minutes, it can be a really big deal indeed. No matter how old the
concrete.

[jerry wass]

Maxwell wrote:
> "Jerry Wass" > wrote in message
> .. .
>
>>> You're right about concrete, but with the low melt temp of aluminum, 20
>>> to 30 pounds of aluminum on a floor at least 2 or 3 years or so old is
>>> not a big deal. But concrete 3 to 6 months old, or higher temp metals can
>>> be real exciting.
>>>
>>> Sand, because it is loose and permeable, can contain 3 to 5% moisture
>>> with no problems at all. As much a 5% is often used for molding.
>>>
>>> Beg to disagree with you , but concrete which was cured properly ( kept
>>> covered
>> or sprayed with water, so that the water can chemicaly combine with the
>> materials
>> in the cement ) has considerable moisture in it known as "water of
>> hydration."--This bond can be broken with the application of heat.--I
>> watched an asphalt storage building burn---the melted asphalt would run
>> out on the floor and burn for a while, until POW! a large piece of the
>> floor would explode flinging concrete & burning asphalt 10 or 20 ft
>> away.---the floor was at least 20 years old or so..Poorly cured concrete
>> still has some water bound up in it, maybe not as much--but it is not as
>> strong as that which was properly cured.
>
> I think you misunderstood Jerry, I agreed he was right about the hazard of
> heat and concrete. My example was from personal experience. Spilling 200 to
> 300 cubic inches of 1400 degree aluminum, on a concrete floor more than a
> few years old, is not usually a really big deal. Uncontained, it will spread
> and quickly cool by 50% in a matter of seconds.
>
> In your example, obviously more than 1400 degrees, with an exposure time of
> many minutes, it can be a really big deal indeed. No matter how old the
> concrete.
>
>
> You sooo right---Ya Know, the reader usually puts more into the statement than
the writer intended..
>
>
>

[Stealth Pilot[_2_]]

On Tue, 27 Jan 2009 16:47:51 -0500, "Morgans"
> wrote:

>
>"Stealth Pilot" > wrote
>
>> hydrogen embrittlement was a big bogey man in home castings but it is
>> easily understood and conquered.
>
>OK, I understand hydrogen embrittlement is a "bad thing" but my question
>is, where does it come from, start, or what do you do to prevent it from
>happening in the first place. I did like your hints for dealing with it,
>and can definitely relate on the hydrochloric acid in the nose bit. Also to
>be considered one of the "bad things." <g>

I'm not an industrial chemist. this comes from watching what happens
in my castings and reading some of the references mentioned.

I first twigged to what may be happening when I grabbed some pistons
that had been sitting outside and plopped them into the part filled
crucible to get the volume up for a pour. they were damp.
I thought a furnace at many hundreds of degrees would dry the stuff
pretty well instantly.
the casting turned out to be like aluminium foam. first time it had
happened to me.
the possible explanation is that the water didnt evaporate but
dissolved into the molten aluminium.
what points me to this is another oddity.
you would think that copper with a melting point of 1500 degrees would
be difficult to incorporate in aluminium which is only at 360 degrees
or so but it isnt so. stir the mix with a copper tube or rod and the
rod will absorb readily into the molten aluminium.

I think that the same thing occurs with water believe it or not.
the fluid appears to dissociate into its component parts in the molten
aluminium.
the oxygen causes lots of oxide froth on the top of the crucible.
the hydrogen remains as a dissolved gas until the aluminium starts to
solidify whereupon it comes out of suspension as bubbles.

where does it come from? any source of moisture that gets to the
molten metal. wet or damp oxide coated stuff that you are recycling
has done it to me. personally I've never found it related to humidity
in the air but Mr Ammen mentions it.

the easiest way I've found of preventing it is to store the scrap
inside and keep it clean and dry. melting clean dry stuff has always
resulted in sound castings for me.

It is a pity the hydrogen bubbles formed on cooling couldnt be
controlled because the foam aluminium is quite light. you just cant
control where the bubbles form and thus the structural integrity.

Stealth Pilot

[Charles Vincent]

Stealth Pilot wrote:
> On Tue, 27 Jan 2009 16:47:51 -0500, "Morgans"
> > wrote:
>
>> "Stealth Pilot" > wrote
>>
>>> hydrogen embrittlement was a big bogey man in home castings but it is
>>> easily understood and conquered.
>> OK, I understand hydrogen embrittlement is a "bad thing" but my question
>> is, where does it come from, start, or what do you do to prevent it from
>> happening in the first place.

> I'm not an industrial chemist. this comes from watching what happens
> in my castings and reading some of the references mentioned.
>

What you are describing is not Hydrogen Embrittlement. Hydrogen
Embrittlement is usually more of an issue for high carbon steels I
believe, though it effects aluminum as well. You can find information
on it under the heading of stress corrosion cracking and it is more of
an environmental issue than casting, as it is a problem for forgings and
weldments as well. It is the mechanism of failure I am pretty sure for
the old VW cases, as magnesium alloys are very susceptable to SCC.

Your description of the problem of the casting problem though is spot
on, if misnamed. Here is a good link on this and other alumminum
casting issues:

<http://www.keytometals.com/Article83.htm>

Charles

[Maxwell[_2_]]

"Charles Vincent" > wrote in message
...
> Stealth Pilot wrote:
>> On Tue, 27 Jan 2009 16:47:51 -0500, "Morgans"
>> > wrote:
>>
>>> "Stealth Pilot" > wrote
>>>
>>>> hydrogen embrittlement was a big bogey man in home castings but it is
>>>> easily understood and conquered.
>>> OK, I understand hydrogen embrittlement is a "bad thing" but my
>>> question is, where does it come from, start, or what do you do to
>>> prevent it from happening in the first place.
>
>> I'm not an industrial chemist. this comes from watching what happens
>> in my castings and reading some of the references mentioned.
>>
>
> What you are describing is not Hydrogen Embrittlement. Hydrogen
> Embrittlement is usually more of an issue for high carbon steels I
> believe, though it effects aluminum as well. You can find information on
> it under the heading of stress corrosion cracking and it is more of an
> environmental issue than casting, as it is a problem for forgings and
> weldments as well. It is the mechanism of failure I am pretty sure for
> the old VW cases, as magnesium alloys are very susceptable to SCC.
>
> Your description of the problem of the casting problem though is spot on,
> if misnamed. Here is a good link on this and other alumminum casting
> issues:
>
> <http://www.keytometals.com/Article83.htm>
>
> Charles

Actually it highlights his misunderstanding of the process. In an effort to
look like he knows something about casting, he began searching the internet
and found reams of confusing material discussing hydrogen embrittlement, and
confused it with hydrogen absorption.

Nice link, by the way, it at least begins to discuss the difficulties of
pouring quality molten aluminum, especially in low volumes if you read
between the lines.

Saying you are going to pour a quality casting from melting old pistons, in
a steel pot, with a propane yard burner - is much like saying you are going
to grind you own crankshaft with a modified wood lathe and a hand grinder.

[Charles Vincent]

Maxwell wrote:

>
> Actually it highlights his misunderstanding of the process. In an effort to
> look like he knows something about casting, he began searching the internet
> and found reams of confusing material discussing hydrogen embrittlement, and
> confused it with hydrogen absorption.
>
> Nice link, by the way, it at least begins to discuss the difficulties of
> pouring quality molten aluminum, especially in low volumes if you read
> between the lines.
>
> Saying you are going to pour a quality casting from melting old pistons, in
> a steel pot, with a propane yard burner - is much like saying you are going
> to grind you own crankshaft with a modified wood lathe and a hand grinder.
>
>

It highlights his misunderstanding of the nomenclature, nothing more.
Not unusual when someone is self taught, especially via trial and error.
I work in a highly technical field and am still plagued by
pronunciations that I assigned to unfamiliar technical terms in my self
study over thirty years ago.
As far as getting quality castings out of a home shop, it takes the same
two things in the home shop as in production. A quality repeatable
process appropriate to the end results desired and essentially a
statistical testing process. Both could be achieved in the home shop,
but will require the casting not of just four heads, but more likely
four hundred castings, with the majority hitting the scrap bin. I
think Veedubers current tack is better alternative.

Charles

[Maxwell[_2_]]

"Charles Vincent" > wrote in message
...
> Maxwell wrote:
>
>>
>> Actually it highlights his misunderstanding of the process. In an effort
>> to look like he knows something about casting, he began searching the
>> internet and found reams of confusing material discussing hydrogen
>> embrittlement, and confused it with hydrogen absorption.
>>
>> Nice link, by the way, it at least begins to discuss the difficulties of
>> pouring quality molten aluminum, especially in low volumes if you read
>> between the lines.
>>
>> Saying you are going to pour a quality casting from melting old pistons,
>> in a steel pot, with a propane yard burner - is much like saying you are
>> going to grind you own crankshaft with a modified wood lathe and a hand
>> grinder.
>>
>>
>
> It highlights his misunderstanding of the nomenclature, nothing more. Not
> unusual when someone is self taught, especially via trial and error. I
> work in a highly technical field and am still plagued by pronunciations
> that I assigned to unfamiliar technical terms in my self study over thirty
> years ago.

Not really. The overwelming issue with hydrogen absorbtion in molten
aluminum is gas porosity, not embrittlement.


> As far as getting quality castings out of a home shop, it takes the same
> two things in the home shop as in production. A quality repeatable
> process appropriate to the end results desired and essentially a
> statistical testing process. Both could be achieved in the home shop, but
> will require the casting not of just four heads, but more likely four
> hundred castings, with the majority hitting the scrap bin. I think
> Veedubers current tack is better alternative.

Not true at all.

[Stealth Pilot[_2_]]

On Sun, 01 Feb 2009 09:13:53 -0600, Charles Vincent
> wrote:

>Stealth Pilot wrote:
>> On Tue, 27 Jan 2009 16:47:51 -0500, "Morgans"
>> > wrote:
>>
>>> "Stealth Pilot" > wrote
>>>
>>>> hydrogen embrittlement was a big bogey man in home castings but it is
>>>> easily understood and conquered.
>>> OK, I understand hydrogen embrittlement is a "bad thing" but my question
>>> is, where does it come from, start, or what do you do to prevent it from
>>> happening in the first place.
>
>> I'm not an industrial chemist. this comes from watching what happens
>> in my castings and reading some of the references mentioned.
>>
>
>What you are describing is not Hydrogen Embrittlement. Hydrogen
>Embrittlement is usually more of an issue for high carbon steels I
>believe, though it effects aluminum as well. You can find information
>on it under the heading of stress corrosion cracking and it is more of
>an environmental issue than casting, as it is a problem for forgings and
>weldments as well. It is the mechanism of failure I am pretty sure for
>the old VW cases, as magnesium alloys are very susceptable to SCC.
>
>Your description of the problem of the casting problem though is spot
>on, if misnamed. Here is a good link on this and other alumminum
>casting issues:
>
><http://www.keytometals.com/Article83.htm>
>
>Charles

not a bad article.
as long as we understand what each other means the semantics isnt too
much of a problem.

hydrogen bubbles through a casting make it more brittle. they
significantly reduce the impact strength which is useful when you want
to smash it up for a retry at a melt. both I and a retired mechanical
engineer I know refer to this as hydrogen embrittlement (of the
casting) if industry has diverged off and use the term in a more
specialised manner good on 'em.

a hydrogen bubbled casting is seldom porous though.it is porous in the
sense that it has voids through it but they arent continuous. if it is
cup shaped you can fill one with water and it wont leak.
as long as we understand what we intend by the words then a little
error in semantics here or there is of no importance.

what I'm describing should be spot on because I'm describing exactly
what I've done. ...in my driveway.

my casting rejection rate would be about 1 in 20, if that.
Stealth Pilot

[Stealth Pilot[_2_]]

On Sun, 1 Feb 2009 12:13:59 -0600, "Maxwell" <#$$9#@%%%.^^^> wrote:

>
>"Charles Vincent" > wrote in message
...
>> Stealth Pilot wrote:
>>> On Tue, 27 Jan 2009 16:47:51 -0500, "Morgans"
>>> > wrote:
>>>
>>>> "Stealth Pilot" > wrote
>>>>
>>>>> hydrogen embrittlement was a big bogey man in home castings but it is
>>>>> easily understood and conquered.
>>>> OK, I understand hydrogen embrittlement is a "bad thing" but my
>>>> question is, where does it come from, start, or what do you do to
>>>> prevent it from happening in the first place.
>>
>>> I'm not an industrial chemist. this comes from watching what happens
>>> in my castings and reading some of the references mentioned.
>>>
>>
>> What you are describing is not Hydrogen Embrittlement. Hydrogen
>> Embrittlement is usually more of an issue for high carbon steels I
>> believe, though it effects aluminum as well. You can find information on
>> it under the heading of stress corrosion cracking and it is more of an
>> environmental issue than casting, as it is a problem for forgings and
>> weldments as well. It is the mechanism of failure I am pretty sure for
>> the old VW cases, as magnesium alloys are very susceptable to SCC.
>>
>> Your description of the problem of the casting problem though is spot on,
>> if misnamed. Here is a good link on this and other alumminum casting
>> issues:
>>
>> <http://www.keytometals.com/Article83.htm>
>>
>> Charles
>
>Actually it highlights his misunderstanding of the process. In an effort to
>look like he knows something about casting, he began searching the internet
>and found reams of confusing material discussing hydrogen embrittlement, and
>confused it with hydrogen absorption.
>
the references I use are aspin and ammin.
I occasionally search the net to see if anyone has a technique that is
better than I'm using but so far they confirm that my teacher was a
master of the art.

>Nice link, by the way, it at least begins to discuss the difficulties of
>pouring quality molten aluminum, especially in low volumes if you read
>between the lines.
>
>Saying you are going to pour a quality casting from melting old pistons, in
>a steel pot, with a propane yard burner - is much like saying you are going
>to grind you own crankshaft with a modified wood lathe and a hand grinder.
>
what baloney.
I use salamander or gold refining crucibles.
I use a waste oil burner of the "major type S" pattern.
in fact when a casting is larger than my crucible can handle I offload
the work to a commercial foundry. they use waterglass and resin
moulding techniques normally but also use greensand.
their greensand techniques vary from mine in the use of machine aids,
other than that we talk and do the same things.

you are so full of it your eyes are brown.
Stealth Pilot

[Maxwell[_2_]]

"Stealth Pilot" > wrote in message
...
> On Sun, 01 Feb 2009 09:13:53 -0600, Charles Vincent
> > wrote:
>
>>Stealth Pilot wrote:
>>> On Tue, 27 Jan 2009 16:47:51 -0500, "Morgans"
>>> > wrote:
>>>
>>>> "Stealth Pilot" > wrote
>>>>
>>>>> hydrogen embrittlement was a big bogey man in home castings but it is
>>>>> easily understood and conquered.
>>>> OK, I understand hydrogen embrittlement is a "bad thing" but my
>>>> question
>>>> is, where does it come from, start, or what do you do to prevent it
>>>> from
>>>> happening in the first place.
>>
>>> I'm not an industrial chemist. this comes from watching what happens
>>> in my castings and reading some of the references mentioned.
>>>
>>
>>What you are describing is not Hydrogen Embrittlement. Hydrogen
>>Embrittlement is usually more of an issue for high carbon steels I
>>believe, though it effects aluminum as well. You can find information
>>on it under the heading of stress corrosion cracking and it is more of
>>an environmental issue than casting, as it is a problem for forgings and
>>weldments as well. It is the mechanism of failure I am pretty sure for
>>the old VW cases, as magnesium alloys are very susceptable to SCC.
>>
>>Your description of the problem of the casting problem though is spot
>>on, if misnamed. Here is a good link on this and other alumminum
>>casting issues:
>>
>><http://www.keytometals.com/Article83.htm>
>>
>>Charles
>
> not a bad article.
> as long as we understand what each other means the semantics isnt too
> much of a problem.
>
> hydrogen bubbles through a casting make it more brittle. they
> significantly reduce the impact strength which is useful when you want
> to smash it up for a retry at a melt. both I and a retired mechanical
> engineer I know refer to this as hydrogen embrittlement (of the
> casting) if industry has diverged off and use the term in a more
> specialised manner good on 'em.

Only in your hemisphere.

>
> a hydrogen bubbled casting is seldom porous though.it is porous in the
> sense that it has voids through it but they arent continuous. if it is
> cup shaped you can fill one with water and it wont leak.
> as long as we understand what we intend by the words then a little
> error in semantics here or there is of no importance.

Then why some people impregnate castings to insure they are leak free.

>
> what I'm describing should be spot on because I'm describing exactly
> what I've done. ...in my driveway.
>
> my casting rejection rate would be about 1 in 20, if that.
> Stealth Pilot
>

And with all that experience, I'm sure you have plenty of photos, not.

[Maxwell[_2_]]

"Stealth Pilot" > wrote in message
...
> On Sun, 1 Feb 2009 12:13:59 -0600, "Maxwell" <#$$9#@%%%.^^^> wrote:
>
>>
>>"Charles Vincent" > wrote in message
...
>>> Stealth Pilot wrote:
>>>> On Tue, 27 Jan 2009 16:47:51 -0500, "Morgans"
>>>> > wrote:
>>>>
>>>>> "Stealth Pilot" > wrote
>>>>>
>>>>>> hydrogen embrittlement was a big bogey man in home castings but it is
>>>>>> easily understood and conquered.
>>>>> OK, I understand hydrogen embrittlement is a "bad thing" but my
>>>>> question is, where does it come from, start, or what do you do to
>>>>> prevent it from happening in the first place.
>>>
>>>> I'm not an industrial chemist. this comes from watching what happens
>>>> in my castings and reading some of the references mentioned.
>>>>
>>>
>>> What you are describing is not Hydrogen Embrittlement. Hydrogen
>>> Embrittlement is usually more of an issue for high carbon steels I
>>> believe, though it effects aluminum as well. You can find information
>>> on
>>> it under the heading of stress corrosion cracking and it is more of an
>>> environmental issue than casting, as it is a problem for forgings and
>>> weldments as well. It is the mechanism of failure I am pretty sure for
>>> the old VW cases, as magnesium alloys are very susceptable to SCC.
>>>
>>> Your description of the problem of the casting problem though is spot
>>> on,
>>> if misnamed. Here is a good link on this and other alumminum casting
>>> issues:
>>>
>>> <http://www.keytometals.com/Article83.htm>
>>>
>>> Charles
>>
>>Actually it highlights his misunderstanding of the process. In an effort
>>to
>>look like he knows something about casting, he began searching the
>>internet
>>and found reams of confusing material discussing hydrogen embrittlement,
>>and
>>confused it with hydrogen absorption.
>>
> the references I use are aspin and ammin.
> I occasionally search the net to see if anyone has a technique that is
> better than I'm using but so far they confirm that my teacher was a
> master of the art.
>
>>Nice link, by the way, it at least begins to discuss the difficulties of
>>pouring quality molten aluminum, especially in low volumes if you read
>>between the lines.
>>
>>Saying you are going to pour a quality casting from melting old pistons,
>>in
>>a steel pot, with a propane yard burner - is much like saying you are
>>going
>>to grind you own crankshaft with a modified wood lathe and a hand grinder.
>>
> what baloney.
> I use salamander or gold refining crucibles.
> I use a waste oil burner of the "major type S" pattern.
> in fact when a casting is larger than my crucible can handle I offload
> the work to a commercial foundry. they use waterglass and resin
> moulding techniques normally but also use greensand.
> their greensand techniques vary from mine in the use of machine aids,
> other than that we talk and do the same things.
>
> you are so full of it your eyes are brown.
> Stealth Pilot

Photos? Photos? Still waiting.

[Morgans[_2_]]

"Stealth Pilot" > wrote
>
> you are so full of it your eyes are brown.

Wrestling with Max is like wrestling with a pig.

You both get dirty, and the pig enjoys it.
--
Jim in NC

[Maxwell[_2_]]

"Morgans" > wrote in message
...
>
> "Stealth Pilot" > wrote
>>
>> you are so full of it your eyes are brown.
>
> Wrestling with Max is like wrestling with a pig.
>
> You both get dirty, and the pig enjoys it.
> --
> Jim in NC
>

Not true. I have never attacked anyone that didn't throw the first punch,
including you.

[Fred the Red Shirt]

On Feb 1, 9:49*am, Stealth Pilot >
wrote:
> ...
>
> I think that the same thing occurs with water believe it or not.
> the fluid appears to dissociate into its component parts in the molten
> aluminium.
> the oxygen causes lots of oxide froth on the top of the crucible.
> the hydrogen remains as a dissolved gas until the aluminium starts to
> solidify whereupon it comes out of suspension as bubbles.
> ...
>

That sounds about right to me.

The solubility of a gas in molten metal increases with the temperature
of the gas. Aluminum, being a reactive metal, reacts readily with
the
oxygen creating dross and leaving the hydrogen in solution until
the metal cools whereupon the bubbles form.

Molten copper does not react readily with oxygen and oxygen bubbles
in cast copper are a problem when the melt is open to the air.

I've never heard of nitrogen bubbles in either metal so I assume the
solubility of nitrogen is very low for each.

[Fred the Red Shirt]

On Feb 2, 3:18*am, Stealth Pilot >
wrote:
> ...
>
> hydrogen bubbles through a casting make it more brittle.

No.

> they
> significantly reduce the impact strength which is useful when you want
> to smash it up for a retry at a melt.

Yes. They make the casting weaker, not more brittle.

Hydrogen embrittlement is also a potential problem with
electrolytic derusting and the the metal isn't even heated.

Hydrogen readily diffuses into cold steel. A bare steel
cylinder will not hold hydrogen for long under high pressure.
Hydrogen cylinders are plated on the inside with nickel.

> ...
> a hydrogen bubbled casting is seldom porous though.it is porous in the
> sense that it has voids through it but they arent continuous. if it is
> cup shaped you can fill one with water and it wont leak.
> as long as we understand what we intend by the words then a little
> error in semantics here or there is of no importance.
> ...

Hydrogen bubbles in a casting won't do anything that other
gas bubbles in a casting do. The only reason you don't
get oxygen bubble in aluminum castings is because the
oxygen reacts with the aluminum. You can get oxygen
bubbles in copper castings, they do the same thing to
copper castings that hydrogen bubbles do to aluminum
castings but that is not called oxygen embrittlement
for the same reason that hydrogen bubbles in aluminum
castings are not called hydrogen embrittlement.

The right words convey the right idea. The wrong words
convey a wrong idea. Harsh words are unnecessary.

The whole point to a newsgroup is to exchange knowledge.

--

FF