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--m--

Posted: Fri Aug 29, 2003 12:22 am

Guest

Hey all, I've just begun starting a PhD which essentially going to be my
M.Sc thesis research on steroids. I've planned out my program, I know what
I want to find out, and what I can contriute to the field in a novel way,
but I am stuck in the HOW department because the device I've bee using is in
serious need of rethinking and improvement. I could really use some input
and ideas, and here's my deal (it may be long, but it's pretty interesting!)

I just finished my M.Sc in a project involving semi-solid slurry processing;
essentially we've created a novel, laboratory-scale "rheocasting" technique.
What this apparatus does is holds two melts (aluminum - A356.2 up to now,
others to follow) in separate furnaces and temperature controls, with
"escape" holes at the bottom of the crucibles. Once the melts are at the
desired temperatures, the exit holes are unplugged and the liquid flows
vertically, under gravity, from the crucibles through 1/2" exit holes, and
into alumina tubes of 3/4" diameter. These tubes, about 14" long and at a
downward angle of perhaps 55-60 degrees or so, are heated so as to eliminate
or minimize heat loss of the melts. The tubes lead to a so-called "mixing
reactor." It's made of copper, coated with graphite spray for improved
fluidity (question 1: does that even make sense?!)...this reactor is just a
3 X 3 X 6 high block that was first split in half, then had a "tortuous
path" end-milled into it to (theoretically, perhaps only intuitively) induce
forced convection and turbulence in the melt streams as they flow through
it. Out of this reactor comes semisolid slurry right below the liquidus
temp, so it's highly fluid but it has a lot of tiny alpha-particles floating
around. This slurry is collected in a crucible, cooled at various rates,
and examined. If you heat the crucible you can keep it a slurry for a bit
longer and directly sample it, which gave the most exciting proof that this
thing works very well. Or you can solidify it and make "SSM feedstock" that
is later reheated and used in thixocasting.

The reactor canals were originally of 1/2" diameter; one of my qualms for
awhile was been that this was just too much of a volumetric flow reduction
for practical purposes. Obvious a lot of heat is sucked through the
melts....the two starting metal pools are reduced to little worms 1/2" in
diameter that run through a criss-crossing pattern that, as it turns out,
doesn't mix the liquids, but makes them bounce off each other and interact
not quite as we'd hoped. We did some similitude experiments with dyed water
to visualize this. Anyway, as the liquids flow through, we are apparently
inducing "copious nucleation" in the liquid metal just below the liquidus
temperature. As in previous rheocasting approaches, we induce forced
convection (hopefully) at the initial stages of solidification, but without
mechanical stirring, but by this "passive" mixing method. And since all of
the expt's up until now have combined melts that were the same alloy
composition and temp, we're not actually "mixing" alloy melts as the name of
the technique suggests. We're simply trying to agitate a crystallizing
aluminum melt in a new way, to replicate the conditions that suppress
dendritic growth in classicial rheocasting pproahces like mechanical
stirring. The holy grail of the field is to devise a continuous SSM
process, and I really think this project is going in that direction...but it
needs a shot of adrenaline into the heart, or perhaps 3.

So with this liquid mixer, if you start with 300g of A356 in each furnace,
with the reactor at room temp and the melts at a superheat of 10 degrees C,
you can obviously only get a certain amount of slurry to flow out of the
reactor, because these two fast-moving streams of aluminum are squeezed
through narrower passages. At a certain point, metal simply freezes within
the reactor, choking off melt flow. This is due to our design of the
reactor (in my defense, the "mentor" who I was working with, who later on
had a violent nervous breakdown and shitstorm of an exit from our
group....he for some reason was just like "fine, try that, we'll see if it
works." I guess we had to start somewhere though...) Nonetheless, the
structures we've seen with this process are excellent, with little spherical
alpha-Al globules as small as 50 microns, and shape factors approaching
0.90, in fairly homogeneous distributions (albeit throughout just under 1
pound of slurry). The problem is this: the reactor isn't optimized, and
wasn't designed with a thorough understanding of how liquid solidifies in
such an odd way (quickly, in a transient, under high cooling rates). We
need to model this, but first we need to figure out exactly what we're
trying to do, and what the best route is. Agitate metal as it crystallizes.
Forced convection. Stabilazation of S/L interface so as to completely
suppress dendrite formation to get good slurries. This concept has deep
ties to very basic casting fundmentals, such as distance solidified under
cetain conditions, etc...but we are dealing with a rather complex pattern.

Any thoughts? I've had a couple insights that turned out to either be too
complex (gotta keep it simple!), or just dumb. An example: analogous to a
butter-churner...circulate the highly fluid slurry in a barrell that keeps
it in the two-phase range and swishes it all around to round out the
particles. My main roadblock right now is that I recently increased the
reactor passages to 3/4" and I've not been getting the same results. Makes
sense in hindsight, but I figured it was good to at least try it and see if
I could get more slurry throughput. But it still chokes off, and now the
slurries I get are composed of a bunch of baby dendrites, so something is
not the same as before.

Back to the drawing board! Looking forward to any thoughtful input, I know
there are some very bright minds in this newsgroup. And trust me, I
wouldn't have typed all this out for delivery to complete strangers unless I
really needed the help. My doctorate is on the line here! One of the
objectives of my doctorate research will be to identify the mechanisms
leading to the development of nondendritic slurres in this process, so that
needs to be addressed as well. There's got to be a way to break this thing
down to little blocks tat I can use to observe what's really going on,
microstructurally. As for the process, I would just be happy if I could
figure a way to modify what we have right now to convert big pools of metal
on the order of pounds (then tens of pounds, for industrial apps) to slurry
of the quality we've gotten with the small sizes of metal seen up til now.
It all lies in the reactor, it needs to change dramatically, I need to
figure out how to use Magma to simulate it (if that even helps....jury's out
on that too).

mmf

Uncle Al

Posted: Fri Aug 29, 2003 9:23 am

Guest

--m-- wrote:
[snip public disclosure of patentable technology]

Quote:

Any thoughts? I've had a couple insights that turned out to either be too
complex (gotta keep it simple!), or just dumb. An example: analogous to a
butter-churner...circulate the highly fluid slurry in a barrell that keeps
it in the two-phase range and swishes it all around to round out the
particles. My main roadblock right now is that I recently increased the
reactor passages to 3/4" and I've not been getting the same results. Makes
sense in hindsight, but I figured it was good to at least try it and see if
I could get more slurry throughput. But it still chokes off, and now the
slurries I get are composed of a bunch of baby dendrites, so something is
not the same as before.

Scientific wild ass guesses,

1) In-line static mixer to violently mix the stream(s) without
moving parts or (much) flow constriction. There are lots of
dimensionless numbers for guestimating hydrodynamic turbulence regimes
if you want to go there.
2) (two-barrel) screw injection molder with high shear.
3) Rotating magnetic field and Lenz' law; baffles to force axial
and saggital mixing in the crucible
4) Ultrasonics

5) Add a "surfactant" to micellize the dispersed phase. It
obviously cannot be an organic detergent or diblock polymer at that
temperature, but the idea is the same: you need an elongated lump one
end of which is only soluble in your dispersed phase and the other in
your surrounding medium. Reduction to practice is left as an exercise
for the alert reader.

If the Chinese read your exposition the Japanese will go ape for
having had it stolen from them as the Koreans are marketing it at
import dumping prices.

[snip]

Quote:

As for the process, I would just be happy if I could
figure a way to modify what we have right now to convert big pools of metal
on the order of pounds (then tens of pounds, for industrial apps) to slurry
of the quality we've gotten with the small sizes of metal seen up til now.
It all lies in the reactor, it needs to change dramatically, I need to
figure out how to use Magma to simulate it (if that even helps....jury's out
on that too).

That's where the fun is. BTW, practical solution first, then
simulation, then fine tuning. The real world is a dirty place. Ab
initio models only accurately model themselves, then researchers
scream "heteroskedasticity!"

--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
"Quis custodiet ipsos custodes?" The Net!

--m--

Posted: Fri Aug 29, 2003 3:26 pm

Guest

"Uncle Al" <UncleAl0@hate.spam.net> wrote in message
news:3F4F6FD6.679C380C@hate.spam.net...

Quote:

--m-- wrote:
[snip public disclosure of patentable technology]

It's patented. What it morphs into will be a different patent, once it
comes about.

Quote:

I read a couple papers from folks who tried this in the 70s at an auto
plant in Europe (Fiat, I think). Didn't seem to catch on though.
Definitely gets rid of the flow constriction problem, but might be a tad
messy. I guess you'd have to devise a chamber to hold the helicals or
whichever geometry might work best.

Quote:

2) (two-barrel) screw injection molder with high shear.

Folks in the UK have one of these, it's pretty nice, but they're only using
Pb-Sn with it last time I checked. And it measures shear rate too.

Quote:

3) Rotating magnetic field and Lenz' law; baffles to force axial
and saggital mixing in the crucible

That's basically what the major commercial route is, Magnetohydrodynamic
stirring, but in essence it's costly and cumbersome. Plus the slurries
we've gotten are much better than the average MHD billet.

Quote:

4) Ultrasonics

That would be interesting. I'll look in to that.

Quote:

5) Add a "surfactant" to micellize the dispersed phase. It
obviously cannot be an organic detergent or diblock polymer at that
temperature, but the idea is the same: you need an elongated lump one
end of which is only soluble in your dispersed phase and the other in
your surrounding medium. Reduction to practice is left as an exercise
for the alert reader.

hmm...I lost you at the lump. Not looking to add anything to the alloy,
that might make those defect thingies.

Quote:

If the Chinese read your exposition the Japanese will go ape for
having had it stolen from them as the Koreans are marketing it at
import dumping prices.

No doubt. But again, it's not the exposition you assumed it was, it was
simply a topic for discussion I thought might generate some ideas. I
wouldn't have thought of posting this if I wasn't comfortable with that
sliiiiightly important tad of business.

Quote:

[snip]

As for the process, I would just be happy if I could
figure a way to modify what we have right now to convert big pools of
metal
on the order of pounds (then tens of pounds, for industrial apps) to
slurry
of the quality we've gotten with the small sizes of metal seen up til
now.
It all lies in the reactor, it needs to change dramatically, I need to
figure out how to use Magma to simulate it (if that even helps....jury's
out
on that too).

That's where the fun is. BTW, practical solution first, then
simulation, then fine tuning. The real world is a dirty place. Ab
initio models only accurately model themselves, then researchers
scream "heteroskedasticity!"

I just said that 5 times fast. Thanks for the ideas.

Quote:

Uncle Al

Posted: Fri Aug 29, 2003 5:02 pm

Guest

--m-- wrote:

Quote:

"Uncle Al" <UncleAl0@hate.spam.net> wrote in message
news:3F4F6FD6.679C380C@hate.spam.net...

--m-- wrote:
[snip public disclosure of patentable technology]

It's patented. What it morphs into will be a different patent, once it
comes about.

Greed is good, greed is right, greed works. A little bit of greed
will get you a whole lot of stuff.

Quote:

Scientific wild ass guesses,

1) In-line static mixer to violently mix the stream(s) without
moving parts or (much) flow constriction. There are lots of
dimensionless numbers for guestimating hydrodynamic turbulence regimes
if you want to go there.

I read a couple papers from folks who tried this in the 70s at an auto
plant in Europe (Fiat, I think). Didn't seem to catch on though.
Definitely gets rid of the flow constriction problem, but might be a tad
messy. I guess you'd have to devise a chamber to hold the helicals or
whichever geometry might work best.

The chamber is simply a pipe. Take a bit of ribbon held by its far
ends and rotate one end 90 degrees vs. the other. That is a static
mixing element. You then stack them so that nothing can leak around
the sides, and touching ends are perpendicular (hence fabrication of a
string of them in a tightly fitting rigid tube; teeny notch like
Lincoln logs in the center of each element's ends for forced
orientation). N elements give you 2^(N-1) mixes. There are only two
big fat caveats:

1) Positive volume injection into each of the two chambers of the
first mixing element determines how everything then proceeds. There
is no requirement that the two flows need be anything near equal
volume... but there absolutely cannot be any backwash at the second
segment's beginning. After that it runs itself.

2) Amazingly, you can get ergodic behavior in which the sum of many
stages of static mixer does *not* result in a homogeneous mixture.
It's been published, with pictures.

Quote:

2) (two-barrel) screw injection molder with high shear.

Folks in the UK have one of these, it's pretty nice, but they're only using
Pb-Sn with it last time I checked. And it measures shear rate too.

Magnesium has been slurry injection molded. It is relatively cheap
and nicely controllable.

Quote:

3) Rotating magnetic field and Lenz' law; baffles to force axial
and saggital mixing in the crucible

That's basically what the major commercial route is, Magnetohydrodynamic
stirring, but in essence it's costly and cumbersome. Plus the slurries
we've gotten are much better than the average MHD billet.

Scale is important. Macro mixing generally won't give you the small
scale violence necessary for structure at scale. Block copolymers
spontaneously controllably separate into spatial domains as relative
block lengths are altered (thermoplastic elastomers - sneakers). One
does not get that hook in alloys.

Quote:

4) Ultrasonics

That would be interesting. I'll look in to that.

If you need massive shear, that will do it. Ultrasonic energy tends
to be a tad expensive on industrial scales. 20 KHz is within human
hearing - ballistic earmuffs!

Quote:

Surfactant is molecular velcro. You have a long molecule. One end is
only soluble in one phase, the other end is only soluble in the other
phase. Interfacial energy betwen two otherwise incompatible phases
drops drastically as one end of the surfactant dissolves in each,
tying them together, allowing a stable dispersion.

Cream is oil dispersed in water stabilized by a protein coating. Give
it enough shear and the phases invert to water dispersed in oil,
called "butter." Mayonnaise is oil dispersed in water stabilized by
egg yolk lecithin as surfactant. If you want to make a pint of world
class oil/vinegar salad dressing, add 250 mg of lecthin (from your
local neighborhood disreputable health food store) and shake. If you
way overdo (blast with a food processor) you get mayonnaise.

Immiscible bulk polymers are nicely compatibilized by adding a percent
of diblock polymer "surfactant," one block of each polymer. The
resulting polymer alloy dispersion can be so fine that the thing goes
transparent.

How one pulls this off in a metal alloy is not obvious. Useful in
principle but not obvious at all.

Similarly, I don't see how you could pour your liquid metal through an
attritor and get out solid less grinding medium on the other end

When in doubt with aluminum, add a fractional percent of scandium.
Tim Worstall will tell you all about that - and supply the scandium.
"8^>)

--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
"Quis custodiet ipsos custodes?" The Net!

--m--

Posted: Fri Aug 29, 2003 6:02 pm

Guest

"Uncle Al" <UncleAl0@hate.spam.net> wrote in message
news:3F4FDBA0.5C5F5FC@hate.spam.net...

Quote:

[snip]

2) Amazingly, you can get ergodic behavior in which the sum of many
stages of static mixer does *not* result in a homogeneous mixture.
It's been published, with pictures.

Ooh ooh, where? I'd love to check that out. I'm going to think more about
this sort of technique. Would be an interesting design project for sure.

Quote:

Scale is important. Macro mixing generally won't give you the small
scale violence necessary for structure at scale.

That is exactly one cornerstone of my intended doctoral work. But I'm not a
process engineer, I'm a metallurgist (more or less). It'll be tricky, but
of course, what's the point of any of this if it never scales up? And what
if there IS a way to not really *have* to scale it up, but to make this
Play-Doh fun factory analog work using, say, different melt velocities? Oh
I don't know. I'm really confused.

Quote:

Similarly, I don't see how you could pour your liquid metal through an
attritor and get out solid less grinding medium on the other end

Even dictionary.com defies definition for "attritor." Whatzit?

Quote:

When in doubt with aluminum, add a fractional percent of scandium.
Tim Worstall will tell you all about that - and supply the scandium.
"8^>)

Ha! Trust me, we got plenty.

Uncle Al

Posted: Fri Aug 29, 2003 7:52 pm

Guest

--m-- wrote:

Quote:

"Uncle Al" <UncleAl0@hate.spam.net> wrote in message
news:3F4FDBA0.5C5F5FC@hate.spam.net...

[snip]

2) Amazingly, you can get ergodic behavior in which the sum of many
stages of static mixer does *not* result in a homogeneous mixture.
It's been published, with pictures.

Ooh ooh, where? I'd love to check that out. I'm going to think more about
this sort of technique. Would be an interesting design project for sure.

I think it was in "Science" some years back, but don't quote me. It
had very nice two-color pictures. Green and yellow? An organiker's
idea of mixing is a magnetic stir bar.

Google
"static mixer" 6630 hits

Ask the experts. They worry about that stuff.

Quote:

Similarly, I don't see how you could pour your liquid metal through an
attritor and get out solid less grinding medium on the other end

Even dictionary.com defies definition for "attritor." Whatzit?

Google
attritor 1140 hits

Ceramic tub. Ceramic shaft sticks up the middle with a few radial
arms. Add ~1/3 fill of round abrasive pebbles. Torque the shaft with
10-100 horsepower and dribble in your stuff into the maelstrom. Stuff
coming out the bottom is sub-micronized. It's nice for dispersing
refractory oxides into pinned superalloys, all solids, then HIP.

It will also molecularly disperse copper phthalocyanine pigment into
Plexiglas beads to make an awesome Phthalo Blue masterbatch for
medical device coloration - no matter what the engineers said. What
does an engineer know about stuff? Engineers make things.

Quote:

When in doubt with aluminum, add a fractional percent of scandium.
Tim Worstall will tell you all about that - and supply the scandium.
"8^>)

Ha! Trust me, we got plenty.

Scandium is the universal aluminum answer, like palladium will solve
every organic synthesis problem. Russian missile skin was
deweaponized into primo baseball bats.

--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
"Quis custodiet ipsos custodes?" The Net!

Richard Saam

Posted: Tue Sep 02, 2003 7:57 am

Guest

Uncle Al wrote:

Quote:

The following first principle relationships will take you a long way.

calculate the shear G

G^2 = P / ( mu V)

and Given two phases calculate D

D = (24/pi) C sigma / ( mu G )

where:

D = Drop size of first phase

G = shear dv/dx

P = mixing power

mu = viscosity

V = volume

C = concentration

sigma = interfacial tension between phases

Richard Saam

--m--

Posted: Tue Sep 02, 2003 5:53 pm

Guest

"mixing power"? Got a unit for that??

No, seriously though thanks for the tip.
"Richard Saam" <rdsaam@att.net> wrote in message news:1l15b.125350$3o3.8812029@bgtnsc05-news.ops.worldnet.att.net...

Uncle Al wrote:

--m-- wrote:
"Uncle Al" <UncleAl0@hate.spam.net> wrote in message
news:3F4FDBA0.5C5F5FC@hate.spam.net...

[snip]
2) Amazingly, you can get ergodic behavior in which the sum of many
stages of static mixer does *not* result in a homogeneous mixture.
It's been published, with pictures.
Ooh ooh, where? I'd love to check that out. I'm going to think more about
this sort of technique. Would be an interesting design project for sure.

The following first principle relationships will take you a long way.

calculate the shear G

G^2 = P / ( mu V)

and Given two phases calculate D

D = (24/pi) C sigma / ( mu G )

where:

D = Drop size of first phase

G = shear dv/dx

P = mixing power

mu = viscosity

V = volume

C = concentration

sigma = interfacial tension between phases

Richard Saam

Richard Saam

Posted: Wed Sep 03, 2003 6:30 am

Guest

--m-

mixing power:

Horsepower (ft lb / sec)
watt (joule / sec)
energy / time

The power (P) (watt) measured at the motor (volt x amp) which drives an
impeller in the liquid.

or

The power (P) ( Q gamma H ) required to pump a fluid through a pipe

Q = flowrate ( ft^3 / sec )
gamma = specific weight (lb / ft^3)
H = head (ft)

Just keep your units consistent.

Remember that mu in

G^2 = P / ( mu V)

is absolute viscosity
and V is volume of the reactor, pipe etc
and shear is change in fluid velocity with distance ( dv/dx ).

Richard Saam

--m-- wrote:

Quote:

"mixing power"? Got a unit for that??

No, seriously though thanks for the tip.

"Richard Saam" <rdsaam@att.net <mailto:rdsaam@att.net>> wrote in
message
news:1l15b.125350$3o3.8812029@bgtnsc05-news.ops.worldnet.att.net...

Uncle Al wrote:

--m-- wrote:

"Uncle Al" <UncleAl0@hate.spam.net> wrote in message
news:3F4FDBA0.5C5F5FC@hate.spam.net...

[snip]

2) Amazingly, you can get ergodic behavior in which the sum of many
stages of static mixer does *not* result in a homogeneous mixture.
It's been published, with pictures.

Ooh ooh, where? I'd love to check that out. I'm going to think more about
this sort of technique. Would be an interesting design project for sure.

The following first principle relationships will take you a long way.

calculate the shear G

G^2 = P / ( mu V)

and Given two phases calculate D

D = (24/pi) C sigma / ( mu G )

where:

D = Drop size of first phase

G = shear dv/dx

P = mixing power

mu = viscosity

V = volume

C = concentration

sigma = interfacial tension between phases

Richard Saam

Tim Worstall

Posted: Thu Sep 04, 2003 12:06 pm

Guest

Uncle Al <UncleAl0@hate.spam.net> wrote in message news:<3F500363.C81AB3BD@hate.spam.net>...

Quote:

--m-- wrote:

"Uncle Al" <UncleAl0@hate.spam.net> wrote in message
news:3F4FDBA0.5C5F5FC@hate.spam.net...

[snip]

2) Amazingly, you can get ergodic behavior in which the sum of many
stages of static mixer does *not* result in a homogeneous mixture.
It's been published, with pictures.

Ooh ooh, where? I'd love to check that out. I'm going to think more about
this sort of technique. Would be an interesting design project for sure.

I think it was in "Science" some years back, but don't quote me. It
had very nice two-color pictures. Green and yellow? An organiker's
idea of mixing is a magnetic stir bar.

Google
"static mixer" 6630 hits

Ask the experts. They worry about that stuff.

Similarly, I don't see how you could pour your liquid metal through an
attritor and get out solid less grinding medium on the other end

Even dictionary.com defies definition for "attritor." Whatzit?

Google
attritor 1140 hits

Ceramic tub. Ceramic shaft sticks up the middle with a few radial
arms. Add ~1/3 fill of round abrasive pebbles. Torque the shaft with
10-100 horsepower and dribble in your stuff into the maelstrom. Stuff
coming out the bottom is sub-micronized. It's nice for dispersing
refractory oxides into pinned superalloys, all solids, then HIP.

It will also molecularly disperse copper phthalocyanine pigment into
Plexiglas beads to make an awesome Phthalo Blue masterbatch for
medical device coloration - no matter what the engineers said. What
does an engineer know about stuff? Engineers make things.

When in doubt with aluminum, add a fractional percent of scandium.
Tim Worstall will tell you all about that - and supply the scandium.
"8^>)

Ha! Trust me, we got plenty.

Quote:

Scandium is the universal aluminum answer, like palladium will solve
every organic synthesis problem. Russian missile skin was
deweaponized into primo baseball bats.
And bike frames and dinky little S&W magnums and tent poles and

lacrosse sticks .....

And coming soon : Wings for jetliners. Another couple of years, and
weld wire for Al Mg Sc alloys.....could even end up welding panes
together, not rivetting.

Sorry.....someone mentioned scandium so I had to jump in :-)

Tim Worstall

Dan Candras

Posted: Tue Sep 09, 2003 1:58 pm

Guest

Quote:

That would be interesting. I'll look in to that.

If you need massive shear, that will do it. Ultrasonic energy tends
to be a tad expensive on industrial scales. 20 KHz is within human
hearing - ballistic earmuffs!

Uncle Al

Posted: Tue Sep 09, 2003 4:28 pm

Guest

Dan Candras wrote:

Quote:

If you think, ultrasonics is to expensive for liquid processing, you
should take a look to
http://www.hielscher.com/ultrasonics/i1000_set.htm. They offer a very
good set for the testing of processes. In bigger scale, they sell a
kilowatt at approx. US$7,000. One kilowatt can process between 1 and
10 gpm. Our company uses an 8kW system made by Hielscher. So far,
there is no superior equipment available.

Regards, Dan

4) Ultrasonics

That would be interesting. I'll look in to that.

If you need massive shear, that will do it. Ultrasonic energy tends
to be a tad expensive on industrial scales. 20 KHz is within human
hearing - ballistic earmuffs!

That is beautiful equipment! Thanks for the link. It brings back
memories of my undergrad Michigan State days wherein it was rumored
one biology building was nothing but a hollow shell housing a
three-story Waring blender and a slanted cow ramp. This is silly at
face value. Anybody who did that would drop in the cows rear first -
to watch the expression on their faces. Today, of course, you could
finance the whole thing with a paid subscription Webcam.

(I won't even hint about the stuff that was displayed for real down
both sides of the main corridor in Anthony Hall.)

--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
"Quis custodiet ipsos custodes?" The Net!

Gordon Couger

Posted: Tue Sep 09, 2003 8:56 pm

Guest

"Uncle Al" <UncleAl0@hate.spam.net> wrote in message
news:3F5E540C.61DA67CD@hate.spam.net...
<sbip>

Quote:

The Animal Science Department has a whole cow grinder here at Oklahoma
State. They kill the cows first though. I can get pictures if you would like
them but it is pretty tame as there is a lid on it. They also built a
scintillation chamber several hundred crystals and photo multiplier tubes
that a full grown live cow would fit in to measure the P 40 in it. That was
impressive before they tore it down.

Things did get exciting when they dumped a live 900 pound steer on the kill
room floor the second day of class in the slaughter class. Someone missed
with the killing gun. There was one city girl that just about lost it ever
day in there.

Gordon Couger
Stillwater, OK
www.couger.com/gcouger

Uncle Al

Posted: Tue Sep 09, 2003 9:41 pm

Guest

Gordon Couger wrote:

Quote:

"Uncle Al" <UncleAl0@hate.spam.net> wrote in message
news:3F5E540C.61DA67CD@hate.spam.net...
sbip
That is beautiful equipment! Thanks for the link. It brings back
memories of my undergrad Michigan State days wherein it was rumored
one biology building was nothing but a hollow shell housing a
three-story Waring blender and a slanted cow ramp. This is silly at
face value. Anybody who did that would drop in the cows rear first -
to watch the expression on their faces. Today, of course, you could
finance the whole thing with a paid subscription Webcam.

(I won't even hint about the stuff that was displayed for real down
both sides of the main corridor in Anthony Hall.)

The Animal Science Department has a whole cow grinder here at Oklahoma
State. They kill the cows first though. I can get pictures if you would like
them but it is pretty tame as there is a lid on it. They also built a
scintillation chamber several hundred crystals and photo multiplier tubes
that a full grown live cow would fit in to measure the P 40 in it. That was
impressive before they tore it down.

Things did get exciting when they dumped a live 900 pound steer on the kill
room floor the second day of class in the slaughter class. Someone missed
with the killing gun. There was one city girl that just about lost it ever
day in there.

Ah, the good old days. Dating was off when the gals appeared with
leather change purses.

--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
"Quis custodiet ipsos custodes?" The Net!

Matt F.

Posted: Mon Sep 15, 2003 5:59 pm

Guest

"Uncle Al" <UncleAl0@hate.spam.net> wrote in message
news:3F5E9D6F.1DBCE1A@hate.spam.net...
sides of the main corridor in Anthony Hall.)

Quote:

The Animal Science Department has a whole cow grinder here at Oklahoma
State. They kill the cows first though. I can get pictures if you would
like
them but it is pretty tame as there is a lid on it. They also built a
scintillation chamber several hundred crystals and photo multiplier
tubes
that a full grown live cow would fit in to measure the P 40 in it. That
was
impressive before they tore it down.

Things did get exciting when they dumped a live 900 pound steer on the
kill
room floor the second day of class in the slaughter class. Someone
missed
with the killing gun. There was one city girl that just about lost it
ever
day in there.

Ah, the good old days. Dating was off when the gals appeared with
leather change purses.

--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
"Quis custodiet ipsos custodes?" The Net!

I did have this funny feeling that I would learn something *really*
interesting when I started this thread.

FYI, I ended up calling off my PhD and am going into industry instead.
Nothing to do with the advice I got on here!

-M.

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