"Tim Douglass" wrote in message
...
On Fri, 13 Jun 2008 14:40:14 -0500, "Leon"
wrote:

An impact that "does not work properly will be tough to hold on to". I
have a 3/8" air ratchet that is holder to hold on to than the 1" that I
used
to use. Needless to say the 3/8" ratchet does not work properly. ;~(

Most air ratchets are not impact tools.

I would not say most, many are not, mine was but needed to be service many
years ago. Most all the mechaics that worked for me used air ratchets that
acted as impacts also.

"Ignoramus29659" wrote in message
...
On 2008-06-14, DoN. Nichols wrote:
On 2008-06-13, Leon wrote:

No load, no nut.

Here's the old video of that impact spinning up.

http://yabe.algebra.com/~ichudov/mis...divx.video.avi

I held it as hard as I could.


Do you have a better link? For me, that only played the sound.

wrote in message
...
On Jun 13, 3:00 pm, Tim Shoppa wrote:

The principal of the impact action is the same regardless of the size.

Precicely, but again that assumes tha tthe impact is operating properly.

I don't remember my mechanics very well, but I do recall that the
mathematics of "impulse" is different from simple statics. Many shots
from a BB gun can move a floating aircraft carrier but the shooter
never feels more than a minor recoil VERY many times. The energy
delivered is large but in tiny, rapid increments.

That breaks it down pretty well.

"Curt Welch" wrote in message
...
"William Noble" wrote:

I've never looked at the design but it's got to be a bit more complex than
that.

No, they are pretty simple tools, they make an electric drill look
complicated.


The rotary hammer can't just be accelerated in a single direction. It's
got to be accelerated in both directions. So after it "hits" the anvil,
it's got to be brought back for the next strike. This requires that the
hammer transfer torque in both directions. As a result, the net torque
sent to the operator can in theory be zero. To make that actually work,
the wrench would need have at least two moving parts - like two hammers
which were taking turns making the strikes and using the momentum of each
other to move - with a net transfer of zero torque to the operator. I
don't know if real torque wrenches work that way, but you would think
those
really large ones would almost have to work that way - or else just
require
they have long handles with two operators to absorb the torque.

I think my logic on this is correct - but maybe I'm just crazy....

Logic is correct but not for this particular tool. Take a look at a
schematic of an impact.



--
Curt Welch
http://CurtWelch.Com/

http://NewsReader.Com/

"J. Clarke" wrote in message
...

The wikipedia article has a video of the operation of the mechanism.

"http://en.wikipedia.org/wiki/Impact_wrench"


That article in fact has a picture of the OP's original picture of the 2
impacts.

"Curt Welch" wrote in message
...
Tim Shoppa wrote:

Still, life is not perfect, and I'll bet that big ass wrench could knock a
very big guy on his butt at times.


More likely if the big guy was off balance when he tried to pick the tool
up. ;~)

"Joe AutoDrill" wrote in message
news:fTA4k.5851$1x.611@trndny06...


Hmm... Define "Makes a living" grin

Yeah. ;~)





It was more of a joke than a serious post although Bob Sapp is probably
one of the scariest human beings on the face of the earth when it comes to
raw strength and size.


Badder than the latest "Hulk"

"SteveB" toquerville@zionvistas wrote in message
...

I think anyone who REALLY knows and understands tools will say, beef don't
matter. And little guys can get just as much done or more by using their
heads, leverage, and by using the tool properly.

That is correct. When I was operating the 1" impact drives I was 22 years
old and a heafty 125 lbs. dripping wet with sweat. I will say that the
first time I looked at it I was very intemidated. One of the mechanics told
me that if I can simply lift it I would have no problem after that. After
grabing and holding on for dear life I was shocked at how little effort was
actually required.

On Sat, 14 Jun 2008 10:03:38 -0800, "SteveB" toquerville@zionvistas
wrote:

As an aside, has anyone seen the Milwaukee .mwv file of the sports car
racing, and pulling in for a pit stop? The mechanic takes off the wheel,
and when he goes to retorque the wheel, the whole car flips over and slams
on its roof. Very nicely done, and very realistic. I have it in my files,
but don't know how to post it. It used to be a URL.

A few weeks back at Lime Rock, I was surprised to see far, far more
18V impact drivers in the pits and garages than air versions.

I remember seeing DeWalt, Milwaukee, and Makita, with about 75%
DeWalt.

There were a mixture of teams, ranging from Joe Gibbs, Roush, and
various factory (Subaru, Acura, VW, BMW, MINI, etc...) road racing
teams, to privateers with open trailers. The use of cordless drivers
was pretty universal.

---------------------------------------------
** http://www.bburke.com/woodworking.html **
---------------------------------------------

As an aside, has anyone seen the Milwaukee .mwv file of the sports car
racing, and pulling in for a pit stop? The mechanic takes off the wheel,
and when he goes to retorque the wheel, the whole car flips over and slams
on its roof. Very nicely done, and very realistic. I have it in my files,
but don't know how to post it. It used to be a URL.

Steve

"Leon" wrote in message
...

"SteveB" toquerville@zionvistas wrote in message
...

I think anyone who REALLY knows and understands tools will say, beef
don't matter. And little guys can get just as much done or more by using
their heads, leverage, and by using the tool properly.

That is correct. When I was operating the 1" impact drives I was 22 years
old and a heafty 125 lbs. dripping wet with sweat. I will say that the
first time I looked at it I was very intemidated. One of the mechanics
told me that if I can simply lift it I would have no problem after that.
After grabing and holding on for dear life I was shocked at how little
effort was actually required.

Yer right. My comments were just a general statement about power tools, and
not any one in particular. But even if it's a simple pry bar, you have to
admit someone who knows how to use it RIGHT will use less effort than some
big Bubba who just uses force.

Steve

Leon wrote:
"SteveB" toquerville@zionvistas wrote in message
...
I think anyone who REALLY knows and understands tools will say, beef don't
matter. And little guys can get just as much done or more by using their
heads, leverage, and by using the tool properly.

That is correct. When I was operating the 1" impact drives I was 22 years
old and a heafty 125 lbs. dripping wet with sweat. I will say that the
first time I looked at it I was very intemidated. One of the mechanics told
me that if I can simply lift it I would have no problem after that. After
grabing and holding on for dear life I was shocked at how little effort was
actually required.





I've been watching this thread and figured I didn't have any real
experience with the tools you guys are discussing. However, when I was
22, I also worked a tool that, while not identical, was similar in
workings. I think. I worked underground in a mine and we used what were
called "jack-legs". Similar to a jack hammer but with a pneumatic leg
that ran out the bottom of the machine on a backward angle to plant
itself in the ground, giving the machine forward thrust.

A bit on varying lengths of drill rod was attached to the front and the
machine drilled holes in a rock face to allow explosives to blow the
wall. We drilled 8-10 feet typically and then loaded with powder.

IIRC, the hardest part was similar to what Leon is saying; pick it up
and get the hole started. Then try to catch your breath and replenish
the quart of sweat you just lost. Turn the machine on and relax til the
hole is finished. Torque on the leg (and the operator) was so minimal as
to be insignificant. But man, did it drill.

Tanus

On Jun 14, 2:56*pm, Tanus wrote:
Leon wrote:
"SteveB" toquerville@zionvistas wrote in message
...
I think anyone who REALLY knows and understands tools will say, beef don't
matter. *And little guys can get just as much done or more by using their
heads, leverage, and by using the tool properly.

That is correct. *When I was operating the 1" impact drives I was 22 years
old and a heafty 125 lbs. dripping wet with sweat. *I will say that the
first time I looked at it I was very intemidated. *One of the mechanics told
me that if I can simply lift it I would have no problem after that. *After
grabing and holding on for dear life I was shocked at how little effort was
actually required.

I've been watching this thread and figured I didn't have any real
experience with the tools you guys are discussing. However, when I was
22, I also worked a tool that, while not identical, was similar in
workings. I think. I worked underground in a mine and we used what were
called "jack-legs". Similar to a jack hammer but with a pneumatic leg
that ran out the bottom of the machine on a backward angle *to plant
itself in the ground, giving the machine forward thrust.

A bit on varying lengths of drill rod was attached to the front and the
machine drilled holes in a rock face to allow explosives to blow the
wall. We drilled 8-10 feet typically and then loaded with powder.

IIRC, the hardest part was similar to what Leon is saying; pick it up
and get the hole started. Then try to catch your breath and replenish
the quart of sweat you just lost. Turn the machine on and relax til the
hole is finished. Torque on the leg (and the operator) was so minimal as
to be insignificant. But man, did it drill.

Tanus

Meh... my grandfather discovered a machine that can take an entire
tractor-trailer apart in 5 seconds. He calls it a locomotive.

"William Bagwell" wrote in message
...
On Sat, 14 Jun 2008 10:03:38 -0800, "SteveB" wrote:

As an aside, has anyone seen the Milwaukee .mwv file of the sports car
racing, and pulling in for a pit stop? The mechanic takes off the wheel,
and when he goes to retorque the wheel, the whole car flips over and slams
on its roof. Very nicely done, and very realistic. I have it in my
files,
but don't know how to post it. It used to be a URL.

This the one?
http://www.youtube.com/watch?v=ziClCExVeF4
--
William

That be the one. Funny, and well done.

Steve

On Sat, 14 Jun 2008 09:31:26 -0500, "Leon"
wrote:


"Tim Douglass" wrote in message
.. .
On Fri, 13 Jun 2008 14:40:14 -0500, "Leon"
wrote:

An impact that "does not work properly will be tough to hold on to". I
have a 3/8" air ratchet that is holder to hold on to than the 1" that I
used
to use. Needless to say the 3/8" ratchet does not work properly. ;~(

Most air ratchets are not impact tools.

I would not say most, many are not, mine was but needed to be service many
years ago. Most all the mechaics that worked for me used air ratchets that
acted as impacts also.

Hmmmm.... Learn something new every day. The only ones I have ever
seen were basically just a turbine & gear reduction.

--
"We need to make a sacrifice to the gods, find me a young virgin... oh, and bring something to kill"

Tim Douglass

http://www.DouglassClan.com

On Sat, 14 Jun 2008 13:53:03 -0700 (PDT), Robatoy
wrote:

Meh... my grandfather discovered a machine that can take an entire
tractor-trailer apart in 5 seconds. He calls it a locomotive.

Sounds like a story behind that...

--
"We need to make a sacrifice to the gods, find me a young virgin... oh, and bring something to kill"

Tim Douglass

http://www.DouglassClan.com

"J. Clarke" wrote:
Curt Welch wrote:
"William Noble" wrote:
"Tim Shoppa" wrote in message

... On Jun 13, 9:48 am, "Leon" wrote:
"Ignoramus9641" wrote in
message

I gotta disagree with you. Law of conservation of angular
momentum -
if you're tranferring that much net torque to the target, that
torque
has to pretty soon make it up to the wrench and whatever's
supporting
the wrench. The rotational inertia of the wrench and plumbing will
take up some small initial amount of impact, and for some trivial
uses (lugnuts) this may be the only important torqueing it does.
Not
true
for a 2.5" on an oilfield!

Tim.

wrong application - the energy transfer is to accelerate a rotary
hammer that then smacks against an anvil delivering an impluse -
when the hammer hits the anvil, neither is connected in any
significant way to the handle - so you have to hold the torque of
accelerating the hammer, not the impact torque (beause the
acceleation is caused by the air motor, and the reaction torque of
the air motor is against the body of the tool)

I've never looked at the design but it's got to be a bit more
complex
than that.

The rotary hammer can't just be accelerated in a single direction.
It's got to be accelerated in both directions. So after it "hits"
the anvil, it's got to be brought back for the next strike.

No, it hits again on the next rotation.

This
requires that the hammer transfer torque in both directions. As a
result, the net torque sent to the operator can in theory be zero.
To make that actually work, the wrench would need have at least two
moving parts - like two hammers which were taking turns making the
strikes and using the momentum of each other to move - with a net
transfer of zero torque to the operator. I don't know if real
torque
wrenches work that way, but you would think those really large ones
would almost have to work that way - or else just require they have
long handles with two operators to absorb the torque.

I think my logic on this is correct - but maybe I'm just crazy....

The wikipedia article has a video of the operation of the mechanism.

"http://en.wikipedia.org/wiki/Impact_wrench"

Yeah, I was just going to look to see if wikipedia had an article on them.
Very interesting, thanks.

That last design they describe with the "rocking hammer" I couldn't really
understand from the description they gave but it sounded a bit like what I
was thinking including the idea of using two hammers.

On the standard design however, it's clear that the torque to spin up the
hammer is constantly being transfered to the operator and the reason it
doesn't produce as much torque as delivered to the nut is simply because
the energy is stored up over a longer period of time as it spins up the
hammer and then delivered in a very short period of time to the nut at a
much higher torque. As was already said, it's just like using a hammer
where the impact of the hammer creates a much greater force than the
operator had to apply to the hammer.

Didn't NASA have to design powered wrenches that would work in space
without causing the astronaut to spin in cycles?

--
Curt Welch http://CurtWelch.Com/
http://NewsReader.Com/

Curt Welch wrote:
"J. Clarke" wrote:
Curt Welch wrote:
"William Noble" wrote:
"Tim Shoppa" wrote in message

... On Jun 13, 9:48 am, "Leon"
wrote:
"Ignoramus9641" wrote in
message

I gotta disagree with you. Law of conservation of angular
momentum -
if you're tranferring that much net torque to the target, that
torque
has to pretty soon make it up to the wrench and whatever's
supporting
the wrench. The rotational inertia of the wrench and plumbing
will
take up some small initial amount of impact, and for some trivial
uses (lugnuts) this may be the only important torqueing it does.
Not
true
for a 2.5" on an oilfield!

Tim.

wrong application - the energy transfer is to accelerate a rotary
hammer that then smacks against an anvil delivering an impluse -
when the hammer hits the anvil, neither is connected in any
significant way to the handle - so you have to hold the torque of
accelerating the hammer, not the impact torque (beause the
acceleation is caused by the air motor, and the reaction torque
of
the air motor is against the body of the tool)

I've never looked at the design but it's got to be a bit more
complex
than that.

The rotary hammer can't just be accelerated in a single direction.
It's got to be accelerated in both directions. So after it "hits"
the anvil, it's got to be brought back for the next strike.

No, it hits again on the next rotation.

This
requires that the hammer transfer torque in both directions. As a
result, the net torque sent to the operator can in theory be zero.
To make that actually work, the wrench would need have at least
two
moving parts - like two hammers which were taking turns making the
strikes and using the momentum of each other to move - with a net
transfer of zero torque to the operator. I don't know if real
torque
wrenches work that way, but you would think those really large
ones
would almost have to work that way - or else just require they
have
long handles with two operators to absorb the torque.

I think my logic on this is correct - but maybe I'm just crazy....

The wikipedia article has a video of the operation of the
mechanism.

"http://en.wikipedia.org/wiki/Impact_wrench"

Yeah, I was just going to look to see if wikipedia had an article on
them. Very interesting, thanks.

That last design they describe with the "rocking hammer" I couldn't
really understand from the description they gave but it sounded a
bit
like what I was thinking including the idea of using two hammers.

On the standard design however, it's clear that the torque to spin
up
the hammer is constantly being transfered to the operator and the
reason it doesn't produce as much torque as delivered to the nut is
simply because the energy is stored up over a longer period of time
as it spins up the hammer and then delivered in a very short period
of time to the nut at a much higher torque. As was already said,
it's just like using a hammer where the impact of the hammer creates
a much greater force than the operator had to apply to the hammer.

Didn't NASA have to design powered wrenches that would work in space
without causing the astronaut to spin in cycles?

I recall that they had come up with some designs, but it looks like
what happens in the real world is that the astronaut secures himself
somehow. The Hubble Space Telescope has special mounting points for
the foot-braces that are used during servicing.

--
--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)

"Tim Douglass" wrote in message
...
On Sat, 14 Jun 2008 09:31:26 -0500, "Leon"
wrote:



Hmmmm.... Learn something new every day. The only ones I have ever
seen were basically just a turbine & gear reduction.



Actually,

"Tim Douglass" wrote in message
...
On Sat, 14 Jun 2008 09:31:26 -0500, "Leon"


Hmmmm.... Learn something new every day. The only ones I have ever
seen were basically just a turbine & gear reduction.



Actually,

A recent design combines an impact wrench and an air ratchet, often called a
"reactionless air ratchet" [4] by the manufacturers, incorporating an impact
assembly before the ratchet assembly. Such a design allows very high output
torques with minimal effort on the operator, and prevents the common injury
of slamming one's knuckles into some part of the equipment when the fastener
tightens down and the torque suddenly increases. Specialty designs are
available for certain applications, such as removing crankshaft pullies
without removing the radiator in a vehicle.

Your statement indicating that you've never looked at the design, explains
why you don't understand the actions involved, and why the rest of your
theories about the tools' actions are incorrect.

The rotational direction of the striking parts is not reversed, doesn't
change direction (unless the user changes the direction of the output to
reverse the direction of rotation of the fastener).

The striking parts work with other parts to deliver glancing blows to the
driven parts (output shaft).

BTW, the impacting action doesn't start until the fastener exhibits some
rotational resistance/opposition to the tool's output (the fastener being
installed becomes seated, a self-locking fastener, rusted or damaged
threads, or a seated fastener needs impacting force to loosen it).
However, mechanics that frequently assemble threaded parts cross-threaded,
will experience the impacting action more often.

The practice of starting the fastener for the first couple of turns with
just finger power generally eliminates the possibility of cross-threading
the fastener.

Normally, the tool acts like a rotational driver unless a high(er) driving
force needs to be applied.

Typically, some torque can be felt by the user that holds an air-operated
impact wrench not attached to a fastener, and gooses the trigger to
wide-open repeatedly, just to hear the tool's exaust noise. This torque is
caused by the tool's air motor rotor jumping from zero/low speed to full
speed, and the counter force of compressed air acting between the tool
housing and the air motor's moving parts.

WB
..........
metalworking projects
www.kwagmire.com/metal_proj.html


"Curt Welch" wrote in message
...

I've never looked at the design but it's got to be a bit more complex than
that.

The rotary hammer can't just be accelerated in a single direction. It's
got to be accelerated in both directions. So after it "hits" the anvil,
it's got to be brought back for the next strike. This requires that the
hammer transfer torque in both directions. As a result, the net torque
sent to the operator can in theory be zero. To make that actually work,
the wrench would need have at least two moving parts - like two hammers
which were taking turns making the strikes and using the momentum of each
other to move - with a net transfer of zero torque to the operator. I
don't know if real torque wrenches work that way, but you would think
those
really large ones would almost have to work that way - or else just
require
they have long handles with two operators to absorb the torque.

I think my logic on this is correct - but maybe I'm just crazy....

--
Curt Welch
http://CurtWelch.Com/

http://NewsReader.Com/

"SteveB" toquerville@zionvistas wrote in message
...

"Joe AutoDrill" wrote in message
news:fTA4k.5851$1x.611@trndny06...
When you hit the 1" and greater, I'll bet the house and car on the
tool, regardless of the weight of Bubba.

Google search Bob Sapp and re-evaluate.

Sorry. If you can't post a cite to back up your argument, it has to be
a weak argument.

Steve

Steve, IIRC Joe makes a living working with this kind of stuff.

Hmm... Define "Makes a living" grin

It was more of a joke than a serious post although Bob Sapp is probably
one of the scariest human beings on the face of the earth when it comes
to raw strength and size. If there is a human who can conquer the larger
tools without beinbg tossed around like a play thing, it's him. Of
course, he probably doesn't have a minute of tool training in him so who
knows...

Regards,
Joe Agro, Jr.

I think anyone who REALLY knows and understands tools will say, beef don't
matter. And little guys can get just as much done or more by using their
heads, leverage, and by using the tool properly.

It is common for a power tool to eat the lunch of even the beefiest
operator when that operator doesn't use the tool properly, or tries to use
muscle over technique. Many amputees will verify this fact of life.

There is no glory in someone being so burly as to use power tools in an
unsafe and unintentioned way over the skinniest guy using it right and
getting the job done and going home with all his fingers. If I had to
work with either, give me the skinny safe operator rather than the
beefcake showoff.

....You must have missed the part where I said it was more of a joke than a
serious post, right? I'm not going to debate the issue when I wasn't
putting myself in the position to defend it in the first place.

However, you are right. Technique and proper use / skill does mean a heck
of a lot more than some or maybe even most people know.

Regards,
Joe Agro, Jr.
(800) 871-5022
01.908.542.0244
Automatic / Pneumatic Drills: http://www.AutoDrill.com
Multiple Spindle Drills: http://www.Multi-Drill.com

V8013-R

"Joe AutoDrill" wrote in message
news:kes5k.8110$1x.5638@trndny06...
"SteveB" toquerville@zionvistas wrote in message
...

"Joe AutoDrill" wrote in message
news:fTA4k.5851$1x.611@trndny06...
When you hit the 1" and greater, I'll bet the house and car on the
tool, regardless of the weight of Bubba.

Google search Bob Sapp and re-evaluate.

Sorry. If you can't post a cite to back up your argument, it has to
be a weak argument.

Steve

Steve, IIRC Joe makes a living working with this kind of stuff.

Hmm... Define "Makes a living" grin

It was more of a joke than a serious post although Bob Sapp is probably
one of the scariest human beings on the face of the earth when it comes
to raw strength and size. If there is a human who can conquer the
larger tools without beinbg tossed around like a play thing, it's him.
Of course, he probably doesn't have a minute of tool training in him so
who knows...

Regards,
Joe Agro, Jr.

I think anyone who REALLY knows and understands tools will say, beef
don't matter. And little guys can get just as much done or more by using
their heads, leverage, and by using the tool properly.

It is common for a power tool to eat the lunch of even the beefiest
operator when that operator doesn't use the tool properly, or tries to
use muscle over technique. Many amputees will verify this fact of life.

There is no glory in someone being so burly as to use power tools in an
unsafe and unintentioned way over the skinniest guy using it right and
getting the job done and going home with all his fingers. If I had to
work with either, give me the skinny safe operator rather than the
beefcake showoff.

...You must have missed the part where I said it was more of a joke than a
serious post, right? I'm not going to debate the issue when I wasn't
putting myself in the position to defend it in the first place.

However, you are right. Technique and proper use / skill does mean a heck
of a lot more than some or maybe even most people know.

Regards,
Joe Agro, Jr.
(800) 871-5022
01.908.542.0244
Automatic / Pneumatic Drills: http://www.AutoDrill.com
Multiple Spindle Drills: http://www.Multi-Drill.com

V8013-R

We agree on that.

On Mon, 16 Jun 2008 07:57:54 -0800, "SteveB" toquerville@zionvistas
wrote:


"Joe AutoDrill" wrote in message
news:kes5k.8110$1x.5638@trndny06...
"SteveB" toquerville@zionvistas wrote in message
...

"Joe AutoDrill" wrote in message
news:fTA4k.5851$1x.611@trndny06...
When you hit the 1" and greater, I'll bet the house and car on the
tool, regardless of the weight of Bubba.

Google search Bob Sapp and re-evaluate.

Sorry. If you can't post a cite to back up your argument, it has to
be a weak argument.

Steve

Steve, IIRC Joe makes a living working with this kind of stuff.

Hmm... Define "Makes a living" grin

It was more of a joke than a serious post although Bob Sapp is probably
one of the scariest human beings on the face of the earth when it comes
to raw strength and size. If there is a human who can conquer the
larger tools without beinbg tossed around like a play thing, it's him.
Of course, he probably doesn't have a minute of tool training in him so
who knows...

Regards,
Joe Agro, Jr.

I think anyone who REALLY knows and understands tools will say, beef
don't matter. And little guys can get just as much done or more by using
their heads, leverage, and by using the tool properly.

It is common for a power tool to eat the lunch of even the beefiest
operator when that operator doesn't use the tool properly, or tries to
use muscle over technique. Many amputees will verify this fact of life.

There is no glory in someone being so burly as to use power tools in an
unsafe and unintentioned way over the skinniest guy using it right and
getting the job done and going home with all his fingers. If I had to
work with either, give me the skinny safe operator rather than the
beefcake showoff.

...You must have missed the part where I said it was more of a joke than a
serious post, right? I'm not going to debate the issue when I wasn't
putting myself in the position to defend it in the first place.

However, you are right. Technique and proper use / skill does mean a heck
of a lot more than some or maybe even most people know.

Regards,
Joe Agro, Jr.
(800) 871-5022
01.908.542.0244
Automatic / Pneumatic Drills: http://www.AutoDrill.com
Multiple Spindle Drills: http://www.Multi-Drill.com

V8013-R

We agree on that.

It doesn't have to be with a complicated tool, either. I knew that
lesson from years of shovelling levees in rice fields, but I relearned
it one summer working construction. I was told to remove the bottom
three courses of a very hard concrete brick from the back of a
building on which we were building an extension. The first day, it
took several hours wailing with all my might with the sledgehammer
just to make a hole (remember, young, 200# 6' and spent my previous
summers shovelling, throwing fertilizer bags by the hundreds for the
crop duster service). I got a few more out that day. The next,
within 30 minutes I was removing each brick with three hits, and not
using all my might but aiming better, and finished before quitting
time.

Pete Keillor

"Steve Ackman" wrote in message
rg...
In , on Fri, 13 Jun 2008 19:54:52 -0400,
J. Clarke, wrote:

Did you happen to see the "Dirty Jobs" episode in which one of the
jobs was changing a tire on a heavy recovery vehicle?


I didn't see the show, but I have to weigh in here.
A heavy recovery vehicle doesn't have tires, it has
tracks. ;-)

** Posted from http://www.teranews.com **

And the Heavy Recovery Vehicle (M88A2) has a 1" hydraulic impact in its
arsenal. The M88A1 was considered a Medium Recovery Vehicle. The M578 is a
Light recovery vehicle and it has tracks too.

The 10-Ton HEMTT (Wrecker) could be considered a Heavy "Wheeled Vehicle"
Recovery Vehicle and it does have large tires. The 900Series 5-Ton Wrecker
would be a Medium/Light Wheeled Recovery Vehicle..

Only the M88, M88A1 and M88A2 have the 1" hydraulic impact wrench (which
runs off the Little Joe APU). There is a lot of feedback to the operator
with one of those. Been there, done that.

Anything else no-one wanted to know?
--
Smitty
Somerset, PA

Bill Smith wrote:
"Steve Ackman" wrote in message
rg...
In , on Fri, 13 Jun 2008 19:54:52
-0400, J. Clarke, wrote:

Did you happen to see the "Dirty Jobs" episode in which one of the
jobs was changing a tire on a heavy recovery vehicle?


I didn't see the show, but I have to weigh in here.
A heavy recovery vehicle doesn't have tires, it has
tracks. ;-)

** Posted from http://www.teranews.com **

And the Heavy Recovery Vehicle (M88A2) has a 1" hydraulic impact in
its arsenal. The M88A1 was considered a Medium Recovery Vehicle. The
M578 is a Light recovery vehicle and it has tracks too.

The 10-Ton HEMTT (Wrecker) could be considered a Heavy "Wheeled
Vehicle" Recovery Vehicle and it does have large tires.

And that is IIRC the vehicle in question. The cameraman was _not_ a
happy camper after the wheel and tire landed on him.

The 900Series
5-Ton Wrecker would be a Medium/Light Wheeled Recovery Vehicle..

Only the M88, M88A1 and M88A2 have the 1" hydraulic impact wrench
(which runs off the Little Joe APU). There is a lot of feedback to
the operator with one of those. Been there, done that.

Anything else no-one wanted to know?

--
--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)

--
Smitty
Somerset, PA
"Steve Ackman" wrote in message
rg...
In , on Tue, 17 Jun
2008 10:22:27 -0400, Bill Smith, wrote:


"Steve Ackman" wrote in message
rg...
In , on Fri, 13 Jun 2008 19:54:52 -0400,
J. Clarke, wrote:

Did you happen to see the "Dirty Jobs" episode in which one of the
jobs was changing a tire on a heavy recovery vehicle?

I didn't see the show, but I have to weigh in here.
A heavy recovery vehicle doesn't have tires, it has
tracks. ;-)

And the Heavy Recovery Vehicle (M88A2) has a 1" hydraulic impact in its
arsenal. The M88A1 was considered a Medium Recovery Vehicle. The M578 is
a
Light recovery vehicle and it has tracks too.

Yup, M88's were exactly what I was thinking of.
A2 version was well after my time. According to
wikipedia A1 was also "Heavy" with only the original
M88 being "Medium." Maybe wikipedia needs a "fix"
on that point?

The M88A1E1 was improved to better tow the M1 Abrams and was considered
Heavy. Officially, you were supposed to use 2 M88A1's to tow an M1. One
front and one behind (to help with braking). I left the service before the
A2 Hercules became widespread. Saw a couple (looked like a modified M1).



I was on the Service side of S&R and S&E platoons,
so I rarely went out on recoveries.

Was a 63Y (Track Mechanic) with the 1st Engineers in the 1stID (1st
Engineers). I lived in an 88.


The 10-Ton HEMTT (Wrecker) could be considered a Heavy "Wheeled Vehicle"
Recovery Vehicle and it does have large tires. The 900Series 5-Ton
Wrecker
would be a Medium/Light Wheeled Recovery Vehicle..

Yup, those too. Even had the "opportunity" to help
change some of those tires. My faded memories seem to
include 3 guys to get those HEMMT tires off the rims.
I'd have sure liked to see that episode of Dirty Jobs.


We'd lift them off with the crane. Much easier.


Only the M88, M88A1 and M88A2 have the 1" hydraulic impact wrench (which
runs off the Little Joe APU). There is a lot of feedback to the operator
with one of those. Been there, done that.

Anything else no-one wanted to know?

There's a couple of wikipedia pages that refreshed
some memories.
http://en.wikipedia.org/wiki/M88_Recovery_Vehicle
http://en.wikipedia.org/wiki/HEMTT

Heh, ever seen an M88A1 try to drive on glare ice over
cobblestones on a slope? Downright funny (though
potentially quite dangerous).

Yep. Or driving thru small towns around Baumholder Germany in the winter. Or
on the autobahn at a whopping 35MPH. Atleast for the big exercises, we
railheaded them.