Today's Message Index:
----------------------
0. 12:04 AM - Coming Soon - The List of Contributors - Please Make A Contribution Today! (Matt Dralle)
1. 02:28 AM - Re: Bussing W58 Series Breakers (Jay Hyde)
2. 02:39 AM - Re: Bussing W58 Series Breakers (Bob Verwey)
3. 06:37 AM - Re: Bussing W58 Series Breakers (Robert L. Nuckolls, III)
4. 07:08 AM - Re: Bussing W58 Series Breakers (Bill Bradburry)
5. 09:05 AM - Re: Bussing W58 Series Breakers (Bill)
6. 09:33 AM - Re: Bussing W58 Series Breakers (Robert L. Nuckolls, III)
7. 10:33 AM - Re: Bussing W58 Series Breakers (R. curtis)
8. 10:45 AM - Re: Bussing W58 Series Breakers (William Mills)
9. 01:04 PM - Copper sheet specs redux (Robert L. Nuckolls, III)
10. 06:40 PM - Re: Bussing W58 Series Breakers (Kelly McMullen)
11. 07:25 PM - Re: Bussing W58 Series Breakers (Bill)
12. 07:31 PM - Re: Bussing W58 Series Breakers (Kelly McMullen)
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Subject: | Coming Soon - The List of Contributors - Please Make |
A Contribution Today!
Each year at the end of the List Fund Raiser, I post a message acknowledging everyone
that so generously made a Contribution to support the Lists. Its my way
of publicly thanking everyone that took a minute to show their appreciation
for the Lists.
Please take a moment and assure that your name is on that List of Contributors
(LOC)! As a number of members have pointed out over the years, the List seems
at least as valuable a building / entertainment tool as your typical magazine
subscription!
Assure that your name is on this year's LOC! Show others that you appreciate the
Lists. Making a Contribution to support the Lists is fast and easy using your
Credit card or Paypal on the Secure Web Site:
http://www.matronics.com/contribution
or by dropping a personal check in the mail to:
Matt Dralle / Matronics
581 Jeannie Way
Livermore CA 94550
I would like to thank everyone that has so generously made a Contribution thus
far in this year's List Fund Raiser! Remember that its YOUR support that keeps
these Lists going and improving! Don't forget to include a little comment about
how the Lists have helped you!
Best regards,
Matt Dralle
Matronics Email List Administrator
Message 1
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Subject: | Bussing W58 Series Breakers |
I do the same, however, the copper tube (I use the stuff that is used as
water pipes in houses) is hard drawn and slightly brittle. To get around
that I use a small blowtorch to heat it up until it glows red hot and then
let it cool in air. That anneals it and makes it softer and more resistant
to cracking and easier to form- like when you flatten it.
Jay
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of R. curtis
Sent: 06 November 2013 10:43 PM
Subject: Re: AeroElectric-List: Bussing W58 Series Breakers
Can a circuit board carry enough current though? The copper layers don't
look very thick. On the other hand, the brass strips that are found in
home electrical stores seem a bit oversized to the task.
Something I have found that works great is soft copper tubing. You can
purchase by the foot at your local hardware store. Take a 1/4" diameter
piece and flatten gently with a hammer and it makes a great bus bar. If you
want to attach it to the CB's with screws you can drill holes and screw it
on or solder if you prefer. a similar method makes a nice forrest of tabs
for grounding.
Roger
_____
.
Do you have a slow PC? <http://www.spamfighter.com/SLOW-PCfighter?cid=sigen>
Try a free scan!
Message 2
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Subject: | Re: Bussing W58 Series Breakers |
C'mon guys, you can buy copper strip cut to size, and save yourself a lot
of hassle. Plus it looks better!
Best...
Bob Verwey
IO 470 A35 ZU-DLW
On 7 November 2013 12:27, Jay Hyde <jay@horriblehyde.com> wrote:
> I do the same, however, the copper tube (I use the stuff that is used as
> water pipes in houses) is hard drawn and slightly brittle. To get around
> that I use a small blowtorch to heat it up until it glows red hot and the
n
> let it cool in air. That anneals it and makes it softer and more resista
nt
> to cracking and easier to form- like when you flatten it.
>
>
> Jay
>
>
> *From:* owner-aeroelectric-list-server@matronics.com [mailto:
> owner-aeroelectric-list-server@matronics.com] *On Behalf Of *R. curtis
> *Sent:* 06 November 2013 10:43 PM
> *To:* aeroelectric-list@matronics.com
> *Subject:* Re: AeroElectric-List: Bussing W58 Series Breakers
>
>
> Can a circuit board carry enough current though? The copper layers don
=92t
> look very thick. On the other hand, the brass strips that are found in
> home electrical stores seem a bit oversized to the task.
>
>
> Something I have found that works great is soft copper tubing. You can
> purchase by the foot at your local hardware store. Take a 1/4" diameter
> piece and flatten gently with a hammer and it makes a great bus bar. If
> you want to attach it to the CB's with screws you can drill holes and scr
ew
> it on or solder if you prefer. a similar method makes a nice forrest of
> tabs for grounding.
>
>
> Roger
>
>
> ------------------------------
>
>
> .
> SPAMfighter href="http://www.spamfighter.com/SLOW-PCfighter?cid=sigen
">slow
> PC? Try a free scan!
>
>
> *www.aeroelectric.com <http://www.aeroelectric.com>*
>
> *www.buildersbooks.com <http://www.buildersbooks.com>*
>
> *www.homebuilthelp.com <http://www.homebuilthelp.com>*
>
> *www.mypilotstore.com <http://www.mypilotstore.com>*
>
> *www.mrrace.com <http://www.mrrace.com>*
>
> *http://www.matronics.com/contribution <http://www.matronics.com/contrib
ution>*
>
> *http://www.matronics.com/Navigator?AeroElectric-List <http://www.matron
ics.com/Navigator?AeroElectric-List>*
>
> *http://forums.matronics.com <http://forums.matronics.com>*
>
> *
>
===========
m>
ldersbooks.com>
.com>
com>
om/contribution>
===========
www.matronics.com/Navigator?AeroElectric-List>
===========
===========
> *
>
>
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Subject: | Re: Bussing W58 Series Breakers |
At 04:38 AM 11/7/2013, you wrote:
>C'mon guys, you can buy copper strip cut to size, and save yourself
>a lot of hassle. Plus it looks better!
>
I'll second that but with foundations in physics. Review
the articles on our website that cite the term "gas tight"
http://tinyurl.com/mjjl9dt
I'll remind Listers that connectivity-magic happens
when two conductors are held together with such force
and rigidity across compliant surfaces that (1) ingress
of moisture laden air and (2) relative motion between
conductors is prevented.
This design goal is the reason why round-wires and
terminals become decidedly un-round under the crush
of a crimped joint -OR- encapsulated in a cocoon of
metal in the soldered joint.
The most problematic joints in a wiring system are
installer-fabricated with poor regard for process.
Threaded fasteners are particularly needful of
attention to details of flatness, force and
rigidity.
This is why the fuse-blocks dropped onto B&C's
counter at OSH turned out to be a kind of
installer's dream for relief of worries about
knowledge and skill sets. First, the metal to
metal joints were minimized. All but the threaded
stud on the end of the assembly are manufactured
for integrity and service life. If the builder
can get a nice flat flag on an AMP terminal
cinched down on a 10-32 stud, probabilities for
very low risk and cost of ownership are good.
The circuit breakers under discussion are
suited to service in appliances and/or systems
were design goals call for protection of a single
feeder. But lining a bunch of them up on a panel
with some notion of bussing their supply terminals
is a mis-application of original design goals.
The technical definition of a buss is a conductive
structure ideally comprised of one piece of
metal from which numerous taps supply power to
various loads in the system with an architecture
that prevents any single failure from propagating
beyond the single feeder. Here's a collection
of pictures for a 'buss and breaker' structure
removed from a legacy Piper airplane . . .
http://tinyurl.com/lmbcm66
http://tinyurl.com/lucl439
http://tinyurl.com/myhmoew
The OBAM aviation builder-sphere is replete
with arguments against religious observation
of legacy design goals, "Well, the guy next
to me in the hanger has been flying this
(you fill in the blank) for years and hasn't
had a bit of trouble."
Given that our art is beginning its second
century of real-life application, there are
constellations of lessons-learned derived
from a distillation of proven recipes for
success re-enforced by understanding of the
physics upon which they're built.
Nobody stands over us with a rule book under
one arm and a citation book under the other . . .
but there ARE folks who we pay to worry that
would be glad to assume that role in our
craft. That event will mark the time when
innovation and exploration of new ideas will
slow to a crawl . . . if not halt completely.
We would do well to expand our understanding of
the arts and science while propagating it to
the greatest number of interested individuals.
There will always be those who don't find
value in this endeavor . . . most will survive
with little more than an elevated cost of
ownership and laundry soap for the underwear.
But a few will become candidates for trial in the Court
of Dark-n-Stormy Nights where the narrator
was not on board the airplane.
The short response is, "buy already mill-flat
materials from which to craft buss bars and
fat-terminal jumpers". It is the exceedingly
rare OBAM aviation shop that can take a round
piece of metal and achieve such flatness.
See: http://tinyurl.com/khymmf3
http://tinyurl.com/leunhah
Bob . . .
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Subject: | Bussing W58 Series Breakers |
There seems to be a typo on this ebay site. I don't think that one cubic
inch of copper weighs 4 pounds! ??
http://www.ebay.com/itm/48-oz-1-16-Flat-Copper-Sheet-Plate-4-x-4-/2711921244
76?pt=LH_DefaultDomain_0
<http://www.ebay.com/itm/48-oz-1-16-Flat-Copper-Sheet-Plate-4-x-4-/271192124
476?pt=LH_DefaultDomain_0&hash=item3f244f6c3c> &hash=item3f244f6c3c
Bill
_____
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert L.
Nuckolls, III
Sent: Thursday, November 07, 2013 9:36 AM
Subject: Re: AeroElectric-List: Bussing W58 Series Breakers
At 04:38 AM 11/7/2013, you wrote:
C'mon guys, you can buy copper strip cut to size, and save yourself a lot of
hassle. Plus it looks better!
I'll second that but with foundations in physics. Review
the articles on our website that cite the term "gas tight"
http://tinyurl.com/mjjl9dt
I'll remind Listers that connectivity-magic happens
when two conductors are held together with such force
and rigidity across compliant surfaces that (1) ingress
of moisture laden air and (2) relative motion between
conductors is prevented.
This design goal is the reason why round-wires and
terminals become decidedly un-round under the crush
of a crimped joint -OR- encapsulated in a cocoon of
metal in the soldered joint.
The most problematic joints in a wiring system are
installer-fabricated with poor regard for process.
Threaded fasteners are particularly needful of
attention to details of flatness, force and
rigidity.
This is why the fuse-blocks dropped onto B&C's
counter at OSH turned out to be a kind of
installer's dream for relief of worries about
knowledge and skill sets. First, the metal to
metal joints were minimized. All but the threaded
stud on the end of the assembly are manufactured
for integrity and service life. If the builder
can get a nice flat flag on an AMP terminal
cinched down on a 10-32 stud, probabilities for
very low risk and cost of ownership are good.
The circuit breakers under discussion are
suited to service in appliances and/or systems
were design goals call for protection of a single
feeder. But lining a bunch of them up on a panel
with some notion of bussing their supply terminals
is a mis-application of original design goals.
The technical definition of a buss is a conductive
structure ideally comprised of one piece of
metal from which numerous taps supply power to
various loads in the system with an architecture
that prevents any single failure from propagating
beyond the single feeder. Here's a collection
of pictures for a 'buss and breaker' structure
removed from a legacy Piper airplane . . .
http://tinyurl.com/lmbcm66
http://tinyurl.com/lucl439
http://tinyurl.com/myhmoew
The OBAM aviation builder-sphere is replete
with arguments against religious observation
of legacy design goals, "Well, the guy next
to me in the hanger has been flying this
(you fill in the blank) for years and hasn't
had a bit of trouble."
Given that our art is beginning its second
century of real-life application, there are
constellations of lessons-learned derived
from a distillation of proven recipes for
success re-enforced by understanding of the
physics upon which they're built.
Nobody stands over us with a rule book under
one arm and a citation book under the other . . .
but there ARE folks who we pay to worry that
would be glad to assume that role in our
craft. That event will mark the time when
innovation and exploration of new ideas will
slow to a crawl . . . if not halt completely.
We would do well to expand our understanding of
the arts and science while propagating it to
the greatest number of interested individuals.
There will always be those who don't find
value in this endeavor . . . most will survive
with little more than an elevated cost of
ownership and laundry soap for the underwear.
But a few will become candidates for trial in the Court
of Dark-n-Stormy Nights where the narrator
was not on board the airplane.
The short response is, "buy already mill-flat
materials from which to craft buss bars and
fat-terminal jumpers". It is the exceedingly
rare OBAM aviation shop that can take a round
piece of metal and achieve such flatness.
See: http://tinyurl.com/khymmf3
http://tinyurl.com/leunhah
Bob . . .
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Subject: | Re: Bussing W58 Series Breakers |
I disagree with letting it "cool in air" *unless* the alloys of copper
water-pipe and spark-plug gaskets differ significantly which I doubt*.*
As a fledgling A&P in 1973 we were taught to heat copper spark-plug gaskets
to "cherry red" and *quench immediately in water*.
I admit having no experience with allowing the gaskets to cool in air.
Here's an EAA demo:
http://www.eaavideo.org/video.aspx?v=57437956001
Respectfully -
Bill
SF bay area
> On 7 November 2013 12:27,
> you
> wrote:
>
>> I do the same, however, the copper tube (I use the stuff that is used as
>> water pipes in houses) is hard drawn and slightly brittle. To get around
>> that I use a small blowtorch to heat it up until it glows red hot and then
>> let it cool in air. That anneals it and makes it softer and more resistant
>> to cracking and easier to form- like when you flatten it.
>>
>
Message 6
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Subject: | Bussing W58 Series Breakers |
At 09:08 AM 11/7/2013, you wrote:
>There seems to be a typo on this ebay site. I don't think that one
>cubic inch of copper weighs 4 pounds! ??
>
><http://www.ebay.com/itm/48-oz-1-16-Flat-Copper-Sheet-Plate-4-x-4-/271192124476?pt=LH_DefaultDomain_0&hash=item3f244f6c3c>http://www.ebay.com/itm/48-oz-1-16-Flat-Copper-Sheet-Plate-4-x-4-/271192124476?pt=LH_DefaultDomain_0&hash=item3f244f6c3c
>
>Bill
>
That's an unfortunate citation. In the time
before etched circuit boards, copper was rated/sold
by gage and/or thickness times some dimension
that described area. Then came copper clad ecb
materials where somebody thought it was a good
idea to speak to the thickness of copper not in
terms of thickness but in some new convention
like 'ounces per square foot'.
It's a close cousin to logic that speaks of 'circular
mil area' of a wire. A 10AWG solid wire is 102 mils
in diameter with a real cross section of
3.14 x (.051)^2 = 0.00816 square inches. 10AWG
said to have a CMA of 102^2 or 10,400 'circular
mils'. It's 'handier' to rate current density in
a wire in Amps per CMA . . . it's a discipline
specific vernacular for folks who work with wires
a lot . . . but it bugs a physicist.
The ounces per square foot are easier to measure/verify
than the actual thickness of the copper where
1 ounce per square foot is 1.344 mils.
Copper has a density of 5.168 oz/cu-in. So a
sheet of copper 1" square and ".001344" thick
will have weight of 5.168 x 0.001344 = .006945
oz/sq-in x 144 = 1.000 oz/sq foot.
Getting back to the eBay ad, we have .062"
thick for 0.323 oz/sq-in x 144 = 46.5
oz/sq-ft. Hence the citation for "48 oz"
copper . . . a description that would be
meaningless to guys who do copper gutters
and flashing . . . or buss bars in airplanes.
Bob . . .
Message 7
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Subject: | Re: Bussing W58 Series Breakers |
I disagree with letting it =22cool in air=22 unless the alloys of copper wate
r-pipe and spark-plug gaskets differ significantly which I doubt.
Air cooling of the cherry red hot copper will anneal it, however it wil
l anneal to a softer state if you quench the copper in water.
Roger
--
Do you have a slow PC=3F Try a Free scan http://www.spamfighter.com/SLOW-PCfi
ghter=3Fcid=sigen
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Subject: | Re: Bussing W58 Series Breakers |
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Message 9
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Subject: | Copper sheet specs redux |
I've had some direct emails asking about the selection
of copper sheet for fabrication of bus bars. It seems
that copper is sold in a market that adopted the Birmingham
guage system as opposed to the Brown and Sharp tables
common to the brass and aluminum markets. Then there's
the stainless steel guys who have their own tables
. . . sigh . . .
This excerpt from a copper sheet gauge table
illustrates the reason why our calculated weight
earlier this morning was a bit different than
the cited weight in the Ebay ad. The "48 oz"
copper being offered was indeed a couple mils
thicker than 1/16" thus explaining the difference.
Emacs!
When bussing breakers the maximum loads you might
see on a bus bar can't be more than alternator
rating. Assume 60A alternator. 10AWG wire example
I cited earlier this morning has a cross section
of 0.0082 sq-in. 10AWG round wire will produce
a 10C rise with 30A of current flowing in it.
If ALL alternator current is fed to the center
of a one-piece bus bar and equally distributed
to half the bus on each side, then the bus carries
30 A max, probably much less.
A 16 Gauge copper buss bar (.065" thick) 1/2"
wide has a copper cross section of .065 x .5 or
0.032 square inches. This is 4x larger than a
10AWG wire so we can expect temperature rise to
be no more than 2.5 degrees C.
Run all the current to one end of the bus bar
such that the whole 60A flows through the copper.
Heating value rises by the square of current. So
2x current is 4x heat or 4x temperature rise so
we're back up to 10C max at end where the feeder
is attached.
The nice thing is that flat copper sheet will reject
heat better than a round wire so the expected rise
will be LESS than the round wire equivalent.
Now, consider the same, 0.064" copper jumped between
two contactor FAT wire terminals. Let's make the jumper
1" wide for 1/2 the resistance per inch of the bus bar
example above. So 60A of alternator current would bring
our rise down to 5C. Hit it with a 200A starter current
for 3x current, 9x rise and the strip of copper could
be expected to rise about 50C during cranking. But it's
got more area than wire and is heat-sinked to the studs
on either end so the heating will be less than 50C. Even
less considering that most cranking intervals are but
a few seconds . . . too short for the rise to stabilize.
This little exercise suggests that .065" copper in 1/2"
wide strips is just fine behind the panel . . . and 1"
strips is okay between contactors, probably no more
marginal for heat rejection than the starter itself. A
piece of 1/8" copper would drop the 50C rise to 25C at
200A in 10AWG wire equivalents . . . MUCH more headroom.
One could fabricate a thicker contactor-jumper from
two layers of 1/16" copper. Get all the joints bright
and clean. Torque the fasteners down tight. All will
be right with the universe.
Bob . . .
Message 10
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Subject: | Re: Bussing W58 Series Breakers |
Hmmm,
Your A&P school had it wrong. With pure copper, such as spark plug
gaskets it makes zero difference whether you quench or not.
Other metals are very different, but copper does not need quenching.
http://en.wikipedia.org/wiki/Annealing_%28metallurgy%29
Quenching with most metals makes it harder, not softer. Copper again is
an exception where quenching doesn't harden, but it doesn't soften either.
On 11/7/2013 10:03 AM, Bill wrote:
> I disagree with letting it "cool in air" */unless/* the alloys of
> copper water-pipe and spark-plug gaskets differ significantly which I
> doubt*.*
> *
> *
> As a fledgling A&P in 1973 we were taught to heat copper spark-plug
> gaskets to "cherry red" and */quench immediately in water/*.
> I admit having no experience with allowing the gaskets to cool in air.
>
> Here's an EAA demo:
> http://www.eaavideo.org/video.aspx?v=57437956001
>
> Respectfully -
> Bill
> SF bay area
>
> On 7 November 2013 12:27,
> you
> wrote:
>
> I do the same, however, the copper tube (I use the stuff that
> is used as water pipes in houses) is hard drawn and slightly
> brittle. To get around that I use a small blowtorch to heat
> it up until it glows red hot and then let it cool in air.
> That anneals it and makes it softer and more resistant to
> cracking and easier to form- like when you flatten it.
>
> *
>
> *
Message 11
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Subject: | Re: Bussing W58 Series Breakers |
Hi Kelly -
Likely it was a time consideration: quench instantly in water rather than
gradually in air.
BTW, water quenching wasn't learned in school. As a "fledgling A&P" I was a
graduate, licensed and employed at an FBO/Repair Station (water quenching
learned here). No matter, both systems work equally well. As I said
initially below; "I admit having no experience with allowing the gaskets to
cool in air". Now I know TWO systems.
Thanks for the input -
Bill
On Thu, Nov 7, 2013 at 6:38 PM, Kelly McMullen <kellym@aviating.com> wrote:
> kellym@aviating.com>
>
> Hmmm,
> Your A&P school had it wrong. With pure copper, such as spark plug gaskets
> it makes zero difference whether you quench or not.
> Other metals are very different, but copper does not need quenching.
> http://en.wikipedia.org/wiki/Annealing_%28metallurgy%29
> Quenching with most metals makes it harder, not softer. Copper again is an
> exception where quenching doesn't harden, but it doesn't soften either.
>
> On 11/7/2013 10:03 AM, Bill wrote:
>
>> I disagree with letting it "cool in air" */unless/* the alloys of copper
>> water-pipe and spark-plug gaskets differ significantly which I doubt*.*
>> *
>> *
>> As a fledgling A&P in 1973 we were taught to heat copper spark-plug
>> gaskets to "cherry red" and */quench immediately in water/*.
>> I admit having no experience with allowing the gaskets to cool in air.
>>
>> Here's an EAA demo:
>> http://www.eaavideo.org/video.aspx?v=57437956001
>>
>> Respectfully -
>> Bill
>> SF bay area
>>
>> On 7 November 2013 12:27,
>> you
>> wrote:
>>
>> I do the same, however, the copper tube (I use the stuff that
>> is used as water pipes in houses) is hard drawn and slightly
>> brittle. To get around that I use a small blowtorch to heat
>> it up until it glows red hot and then let it cool in air.
>> That anneals it and makes it softer and more resistant to
>> cracking and easier to form- like when you flatten it.
>>
>> *
>>
>> *
>>
>
>
Message 12
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Subject: | Re: Bussing W58 Series Breakers |
Sure. I maintain enough extra gaskets that I put fresh ones on, the
anneal the old ones at my leisure. I just string them on some old safety
wire, heat, then let cool and they are ready for next plug servicing.
On 11/7/2013 8:23 PM, Bill wrote:
> Hi Kelly -
>
> Likely it was a time consideration: quench instantly in water rather
> than gradually in air.
>
> BTW, water quenching wasn't learned in school. As a "fledgling A&P" I
> was a graduate, licensed and employed at an FBO/Repair Station (water
> quenching learned here). No matter, both systems work equally well. As
> I said initially below; "I admit having no experience with allowing
> the gaskets to cool in air". Now I know TWO systems.
>
> Thanks for the input -
> Bill
>
> On Thu, Nov 7, 2013 at 6:38 PM, Kelly McMullen <kellym@aviating.com
> <mailto:kellym@aviating.com>> wrote:
>
> <kellym@aviating.com <mailto:kellym@aviating.com>>
>
> Hmmm,
> Your A&P school had it wrong. With pure copper, such as spark plug
> gaskets it makes zero difference whether you quench or not.
> Other metals are very different, but copper does not need
> quenching. http://en.wikipedia.org/wiki/Annealing_%28metallurgy%29
> Quenching with most metals makes it harder, not softer. Copper
> again is an exception where quenching doesn't harden, but it
> doesn't soften either.
>
> On 11/7/2013 10:03 AM, Bill wrote:
>
> I disagree with letting it "cool in air" */unless/* the alloys
> of copper water-pipe and spark-plug gaskets differ
> significantly which I doubt*.*
> *
> *
> As a fledgling A&P in 1973 we were taught to heat copper
> spark-plug gaskets to "cherry red" and */quench immediately in
> water/*.
> I admit having no experience with allowing the gaskets to cool
> in air.
>
> Here's an EAA demo:
> http://www.eaavideo.org/video.aspx?v=57437956001
>
> Respectfully -
> Bill
> SF bay area
>
> On 7 November 2013 12:27,
> you
> wrote:
>
> I do the same, however, the copper tube (I use the
> stuff that
> is used as water pipes in houses) is hard drawn and
> slightly
> brittle. To get around that I use a small blowtorch
> to heat
> it up until it glows red hot and then let it cool in
> air. That anneals it and makes it softer and more
> resistant to
> cracking and easier to form- like when you flatten it.
>
> *
>
> *
>
>
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