Today's Message Index:
----------------------
1. 05:03 AM - Re: icom ic-a200 (Sam Hoskins)
2. 05:03 AM - Re: icom ic-a200 (Sam Hoskins)
3. 05:05 AM - Re: icom ic-a200 (Ken)
4. 05:06 AM - Re: Crimping of machined D-sub pins with 4-Way Indent Pin Crimper (Andrew Butler)
5. 05:20 AM - icom (bob noffs)
6. 06:24 AM - Re: Need for start up protection (Robert L. Nuckolls, III)
7. 06:27 AM - Re: Need for start-up protection? ()
8. 06:35 AM - Re: Crimping of machined D-sub pins (Robert L. Nuckolls, III)
9. 08:03 AM - Grounding Of Fuel Senders (Dave VanLanen)
10. 08:07 AM - Re: Need for start-up protection? (Robert L. Nuckolls, III)
11. 08:46 AM - Re: Grounding Of Fuel Senders (Ralph E. Capen)
12. 10:18 AM - Re: Grounding Of Fuel Senders (F. Tim Yoder)
13. 01:42 PM - Re: Crimping of machined D-sub pins with 4-Way Indent Pin Crimper (MauleDriver)
14. 07:06 PM - Re: Grounding Of Fuel Senders (Robert L. Nuckolls, III)
Message 1
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Subject: | Re: icom ic-a200 |
Bob,
I just finished my IC-A210 installation and I do have pins R&14 connected.
Except for getting my old GPSMap196 to talk to the A21, everything seems to
be working. I have been corresponding with ICOM Tech
Support<http://www.icomamerica.com/en/contactus.aspx>and there is has
been no mention of removing the wire at R.
Sam
On Thu, Dec 11, 2008 at 10:27 PM, bob noffs <icubob@newnorth.net> wrote:
> hi all,
> this is to anyone that has recently wired or looked at the installation
> manual for this radio.
> i wired this radio over a year ago and everything tested out fine. today i
> was reinstalling all of my wiring for the last time and i noticed a wire was
> broken at the molex connector. actually it looks more like i cut it. i cant
> remember if i did cut it or why. the connector is pin R. pin R and pin 14
> connect to the power feed from the bus. the schematic calls for the power to
> go to these 2 pins. anyone know of a reason to feed pin14 and not pinR ?
> any input appreciated.
> bob noffs
>
> *
>
>
Message 2
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Subject: | Re: icom ic-a200 |
Bob,
I just finished my IC-A210 installation and I do have pins R&14 connected.
Except for getting my old GPSMap196 to talk to the A21, everything seems to
be working. I have been corresponding with ICOM Tech
Support<http://www.icomamerica.com/en/contactus.aspx>and there is has
been no mention of removing the wire at R.
Sam
On Thu, Dec 11, 2008 at 10:27 PM, bob noffs <icubob@newnorth.net> wrote:
> hi all,
> this is to anyone that has recently wired or looked at the installation
> manual for this radio.
> i wired this radio over a year ago and everything tested out fine. today i
> was reinstalling all of my wiring for the last time and i noticed a wire was
> broken at the molex connector. actually it looks more like i cut it. i cant
> remember if i did cut it or why. the connector is pin R. pin R and pin 14
> connect to the power feed from the bus. the schematic calls for the power to
> go to these 2 pins. anyone know of a reason to feed pin14 and not pinR ?
> any input appreciated.
> bob noffs
>
> *
>
>
Message 3
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Subject: | Re: icom ic-a200 |
Bob
A few years ago I traced all those multiple power and also the ground,
and signal ground connections on my A200 and found that they were all
connected together inside the radio. Suspect they were encouraging
redundant connections but there is no actual need for them.
On another thread, I almost always start and shut down with power on
this radio and no problems so far after a couple of hundred hours. No
radio master switch but OTOH one real overvoltage event was trapped by
my overvoltage protection.
Ken
bob noffs wrote:
> hi all,
> this is to anyone that has recently wired or looked at the installation
> manual for this radio.
> i wired this radio over a year ago and everything tested out fine.
> today i was reinstalling all of my wiring for the last time and i
> noticed a wire was broken at the molex connector. actually it looks more
> like i cut it. i cant remember if i did cut it or why. the connector is
> pin R. pin R and pin 14 connect to the power feed from the bus. the
> schematic calls for the power to go to these 2 pins. anyone know of a
> reason to feed pin14 and not pinR ?
> any input appreciated.
> bob noffs
Message 4
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Subject: | Re: Crimping of machined D-sub pins with 4-Way |
Indent Pin Crimper
Good stuff indeed.
Now only last week I installed my Ray Allen elevator trim and attached the AWG24
to AWG22 using D-SUB PINS. One of the AWG 24 wires did indeed disconnect, and
I incorrectly (thanks guys) assumed that I hadn't crimped it right. I redid
it and gave all the pins tug. They stuck fast. Now I know I was lucky.
Next I joined up the MALE FEMALE D-SUB pins and covered each connection in heatshrink.
Then I bundled the lot together and covered with a single larger piece
of heat shrink.
I installed the trim assembly with the heatshrinked bundle poking through the bushing
in the elevator spar. Nice job done (I thought).
Do I need to redo it?
If so, why? i.e. what are the realistic failure modes that the AWG24 side of the
connections might contibute to, in this case, given that I tested each crimp
and each one has two layers of heat shrink holding them together?
Andrew Butler
RV71700
Galway, Ireland.
----- Original Message -----
From: "MauleDriver" <MauleDriver@nc.rr.com>
Sent: Thursday, 11 December, 2008 10:09:54 PM GMT +00:00 GMT Britain, Ireland,
Portugal
Subject: Re: AeroElectric-List: Crimping of machined D-sub pins with 4-Way
Indent Pin Crimper
Thanks Bob! That is exactly the problem I have and the solution I'll apply.
It is an Eclipse (should have said that before). The barrel dimension
is .302" rather than .260".
This is has been a valuable exercise for this builder because I come
away with a better understanding of the process and the tools. And a
better understanding of how, as a homebuilder, I can learn and adapt
processes and tools to the building and maintaining of my custom craft.
I guess I'm just saying I grew a bit here.
Thanks to all of you that helped on and off the list. Good stuff.
Bill Watson
Robert L. Nuckolls, III wrote:
> <nuckolls.bob@aeroelectric.com>
>
> At 11:33 AM 12/10/2008, you wrote:
>> I think I have several problems and oversights that need to be
>> addressed.
>>
>> I'm using a tool that looks like this:
>> http://aeroelectric.com/Pictures/Tools/Crimp_Tools/rct-3.jpg
>> As you said, it is setup for one size of wire and one type of
>> pin/socket. I've been using it on 20AWG and probably 22 AWG which
>> would immediately indicate some inconsistency. But in this case, I
>> was using it on 24AWG wires that was part of a pre-made harness pig
>> tail.
>>
>> In addition, I was trying to strip the wire just far enough to barely
>> clear or be flush with the pin. Given that this crimper seems to
>> crimp concentrically at the the very tip of the pin, allowing any of
>> the insulation into the pin could further compromise the crimp. (I'm
>> attaching 2 pics of the pin that failed).
>> I first need to determine what size wire the crimper is setup for and
>> limit its use to that wire. And re-confirm I'm using the right pins
>> (non-high density).
>>
>> For this particular connection involving the 24AWG wires, I'm going
>> to follow your guidance on using a 9 pin D-sum with solder terminals
>> along with shrink tubing, clear adhesive and more shrink tubing.
>> It's a good solution for this particular connection.
>>
>> I'll have to take a closer look at the adjustable Daniels crimper if
>> I want to get serious... but it may be too expensive to justify.
>>
>> What do you think?
>
> Thanks for the great pictures. I've added those to my
> reference library. It seems that Eclipse is back to their
> old habits.
>
> When I started stocking that tool many moons ago, I
> discovered that the pin-positioner was cut wrong
> allowing the pin to set too deep in the tool. This
> causes the crimp to happen too far back on the wire
> grip as shown here . . .
>
> http://aeroelectric.com/Pictures/Tools/Crimp_Tools/4-Quad/Positioner_Mod_0.jpg
>
>
> I used to check every tool and modify as shown
> here . . .
>
> http://aeroelectric.com/Pictures/Tools/Crimp_Tools/4-Quad/Positioner_Mod_1.jpg
>
>
> I put every positioner in the lathe and cut it back
> on the pin-entry end to achieve the dimension shown.
> This moved the pin up in the too such that the
> wire-grip was just flush to slightly under-flush
> with the face of the tool.
>
> B&C checked the tools too after I turned that
> activity over to them. Tim reported to me some
> months later that the pin-positioners were coming
> in okay. I figured that it was the result of a
> letter I wrote to Eclipse citing the problem.
>
> The other part of your problem is putting 24AWG wires
> into a 20/22 AWG pin. The tool is designed to have a slightly
> over-crimp on 20AWG and slightly under-crimp on 22AWG.
> This means it's way under-crimped for 24AWG. You fix this
> by striping 24AWG wire 2X length for exposed strands and
> fold the strands back to double the amount of copper
> in the finished joint.
>
> Alternatively, your idea of a fixed "plug" in the
> bottom of the pin-positioner works too but you
> have to be VERY careful about too much plug . . .
> it can be hard to get out. You can use a small
> twist drill to clear the hole.
>
> Bob . . .
>
>
Message 5
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sam and ken,
you guys answered my questions 100%.
thanks , bob noffs
Message 6
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Subject: | Re: Need for start up protection |
At 11:05 PM 12/11/2008, you wrote:
>
>OK, I've read the debate on the need for start-up protection and I
>can no longer resist the temptation to weigh in with my 2 cents' worth:
Mike, when you reply to a digest message, it's really
important that you trim off the non-relevant body of
text that you're speaking to. All of our responses are
archived and poorly or un-trimmed responses can really
load the system with "stuff" that makes it difficult
for historians to retrieve value from the archives
later.
>1) With all due respect to my learned colleagues, I worked in the
>aerospace industry for many years and have seen more than one
>product pass DO-160 testing and subsequently fail in-service due to
>aircraft electrical system issues. There are lots of reasons why
>this should not happen, but there are also lots of reasons why it does happen.
>
>2) Many of the tests in DO-160 have a number of test categories with
>differing severity based on the anticipated electrical system
>characteristics to which the product will be exposed. However, the
>"anticipated" characteristics may or may not reflect the actual
>characteristics of any given OBAM aircraft. Further, not all
>equipment is necessarily tested to the most severe category of DO-160.
Your first-hand experiences cannot be argued with.
But we do know that there are reasons for everything.
The simple-ideas in physics and practice (repeatable
experiments) are irrefutable.
If you have observed failures attributed to incompatibility
between accessory and power source, what was the feature
that failed to meet design goals and what was done to
correct it?
Part of my livelihood involves investigation into
"unanticipated" characteristics . . . because
such behaviors are considered failure to meet
design goals.
You have alluded to "actual characteristics
of any given OBAM aircraft". Let us hypothesize
what it would take to cause any aircraft to present
stresses that lie outside the test parameters of
the most relaxed DO-160 recommendation for
robustness.
What piece of hardware would you modify to produce
the sought after event? What would be the nature
of the resultant stress? Amplitude? Duration? Total
energy? How would that modification be expected to
occur in practice as one of our brothers puts his
airplane together?
If you're operating under the premise that DO-160/Mil-Std-704
compliance is fraught with risk, then from what deficiency
of specification, design or craftsmanship does the risk
arise?
When I am chartered to deduce root cause of anomalous
behavior, my customers would probably not pay my bill
if my proffered solution was, "turn the thing off
while you crank the engine." My charter is to identify
the deficiency and correct it . . . not craft out
a work-around to live with it. "Living with it" is
a tacit admission that we're probably not qualified
for the job!
>3) My aircraft is day/VFR, so a total electrical failure is a
>nuisance, not a crisis. Balancing the mission profile of MY
>aircraft and based upon my points above, I would rather deal with
>the risk of a single-point failure of the avionics master switch as
>opposed to the risk of damage to my avionics.
>The foregoing is, admittedly, a personal choice that may not reflect
>others' situations or opinions. I think it best that we concede
>that, like politics and religion, reasonable minds may differ on the
>need for start-up protection. As Bob has said many times, as
>aircraft builders we must each make the choices that we deem
>appropriate for our aircraft.
That's a really broad brush. Most of what passes for
politics and religion requires individuals be persuaded
to adopt a behavior based on goals of others . . .
when both should be matters of precise PERSONAL choice
borne of honorable behavior and understanding.
Let us not drive the art of aircraft fabrication based
on fear of what we do not know (perceived risk) when
conditions driving that fear are not qualified,
quantified, nor accompanied by deduction of root
cause and successful remedy (repeatable experiment).
If you're citing experiences with a notion of enhancing
our knowledge and confidence, then they must be supported
by quality, quantity and remedy. Otherwise, it can
serve only to persuade based on fear of that which is
imagined.
Bob . . .
Message 7
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Subject: | Need for start-up protection? |
We are all enlightened by the process. It is however unavoidable that we
are using more $$$ avionics today on top of a system that was designed
too many years ago and has not kept step with other industries. It's
sort of like buying a 32" monitor for a 286 PC (remember those?). I've
got 30k + on the face of my panel and I should probably be concerned
about a motherboard designed back in the 30's. This is where we industry
has left us. We've got marketers and we've got engineers. The marketers
are freelancers and the engineers have their hands tied.
It's time to get some of this cooped up engineering into the fundamental
systems of GA aircraft. You know the big guys have it. I look at the
electrical system in my Porsche and the one in my Lancair and that makes
my head itch. By today's standard the one in my Lancair could have been
designed by an EE freshman which got a "C" in class. Sure it works, but
it doesn't pass muster with what is available to industry.
So here we are, Garmin selling us $100k panels to lay on top of our $20
solenoids. Let's hope the wires don't touch. Oh yes, don't forget to
shut off those fancy gadgets before turning the key.
gl
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of F.
Tim Yoder
Sent: Thursday, December 11, 2008 7:13 PM
Subject: Re: AeroElectric-List: Need for start-up protection?
<ftyoder@yoderbuilt.com>
I agree, I believe this attitude prevails throughout industry, not
limited
to the general aviation industry.
Another interesting ramification is the "Not Invented Here" syndrome. My
father was a Roto Gravure specialist and Inventor, as manager of Formica
Corp. he was unable to get many of his inventions out of their R&D Dept.
without the dept. heads name being included on the application. As you
suggested, many are more interested in their personal status than doing
what
is best for the company.
I'm learning allot following the AeroElectric-List, thanks to your,and
others, participation...
Tim
----- Original Message -----
From: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>
Sent: Thursday, December 11, 2008 8:17 AM
Subject: Re: AeroElectric-List: Need for start-up protection?
<nuckolls.bob@aeroelectric.com>
>
> At 02:55 PM 12/10/2008, you wrote:
> ><ftyoder@yoderbuilt.com>
> >
> >Bob,
> >I'm getting the impression you are fighting a Up Hill battle.
> >However, the new plane I'm building will not have an Avionics Master
Switch.
> >
> >An Old Dog has learned a new trick!
>
> I don't fight battles. Gave that exercise up about 20
> years ago when I went to work for OEM air-framers. One
> can only be true to one's craft. Study the simple ideas
> and how they assemble into useful inventions (good
> engineering). Be willing to share that knowledge and
> understanding (good teaching). But don't be discouraged
> because managers with power over project will have
> reasons for embracing alternatives (self preservation).
>
> It's interesting that I'm presently working on a project
> that I proposed to my management about 5 years ago to
> replace a piece of 1970 technology (4 x 4 x 6" box
> full of discrete components for $20K) with a new
> design (2 x 2 x 1" box, thimbleful of discretes
> and a microprocessor for $1K). We had the people,
> the facilities and the excitement to make it happen
> in-house. I had concurrence all the way up to the
> chief scientist.
>
> I'm brass-boarding the replacement product now as
> a consultant to a supplier. My milestone presentation
> on the project will be attended by many of those who
> opposed doing it in the first place. I'm betting that
> even if they remember my earlier proposal, they'll not
> be the least bit embarrassed. It's their position that
> we should stick to our "core competency" . . . assembling
> purchased tinker-toys into airplanes. There's no need
> to understand how the tinker-toys work!
>
> I'm finding that this attitude prevails throughout the
> general aviation industry. When I began working with
> GA about 1975, folks in those facilities knew more
> about my craft than I did. Many were my teachers.
> Now it's rare to find even the most rudimentary
> understanding of electronics at the OEM's.
>
> The point of this long story is to re-enforce the
> notion that there are folks with control of
> a project that don't cherish confidence that
> comes from understanding. The only path open
> is to cling to tradition and cover their #$$@#
> with lots of specs and requirements. If and when
> the project flops, they are guiltless as long as
> they produced the "golden requirements". It's
> up to somebody else to deliver to those requirements.
>
> It matters not that what they've asked for can not
> . . . or should not be done. Our brothers building
> airplanes are faced with many of the same
> decisions placed before the managers at BeePipCesMo.
> We can only be willing to share understanding. The ability/
> willingness of individuals to exploit that understanding
> is out of our hands. It benefits nobody for you or I
> to bring clubs and shields to the conversation.
>
> Bob . . .
>
>
Message 8
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Subject: | Re: Crimping of machined D-sub pins |
At 07:05 AM 12/12/2008, you wrote:
><andrewbutler@ireland.com>
>
>Good stuff indeed.
>
>Now only last week I installed my Ray Allen elevator trim and
>attached the AWG24 to AWG22 using D-SUB PINS. One of the AWG 24
>wires did indeed disconnect, and I incorrectly (thanks guys) assumed
>that I hadn't crimped it right. I redid it and gave all the pins
>tug. They stuck fast. Now I know I was lucky.
>
>Next I joined up the MALE FEMALE D-SUB pins and covered each
>connection in heatshrink. Then I bundled the lot together and
>covered with a single larger piece of heat shrink.
>
>I installed the trim assembly with the heatshrinked bundle poking
>through the bushing in the elevator spar. Nice job done (I thought).
>
>Do I need to redo it?
What is the risk of having the trim actuator fail
to function? It's probably not a big deal in terms of
getting the airplane back on the ground without
breaking a sweat.
What's the cost of ownership issue for having to
fix it at a later date versus doing something about
it now?
Any offer by me or anyone else to assess risk will
be based on magnitudes pulled from where the sun
don't shine. I'll suggest it's a matter of personal
choice taking into consideration that the technology
used was misapplied to the task (too small wire for
a 22/20AWG pin).
>If so, why? i.e. what are the realistic failure modes that the AWG24
>side of the connections might contibute to, in this case, given that
>I tested each crimp and each one has two layers of heat shrink
>holding them together?
Here's an alternative for joining those @$@#$@# 24AWG
conductors to ship's wiring.
http://www.aeroelectric.com/articles/macservo/macservo.html
There are other connector technologies that would work
just as well.
Bob . . .
Message 9
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Subject: | Grounding Of Fuel Senders |
I am installing VDO fuel senders in the metal fuel tanks of my all-metal kit
aircraft. These senders do not have a ground lug, and the sender, by
design, is not isolated from the fuel tank because the mounting screws are
inserted into a metal mounting ring which is in metal-to-metal contact with
the inside of the fuel tank. The construction manual calls for grounding
the sender to the airframe using a wire from the airframe to a ring terminal
under one of the mounting screws. My concern with this approach is that I
might inadvertently introduce a "ground loop" into the system by grounding
in this fashion. I would prefer to isolate the sender from the airframe and
run a return wire to the universal ground buss on the firewall, but because
of the design of the sender this would be difficult to do. Has anyone else
dealt with installation of these senders, and if so, can you offer me any
advice?
Thanks,
Dave Van Lanen
Message 10
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Subject: | Need for start-up protection? |
>It's time to get some of this cooped up engineering into the fundamental
>systems of GA aircraft. You know the big guys have it. I look at the
>electrical system in my Porsche and the one in my Lancair and that makes
>my head itch. By today's standard the one in my Lancair could have been
>designed by an EE freshman which got a "C" in class. Sure it works, but
>it doesn't pass muster with what is available to industry.
In what way? Can you help us understand how that box of
plastic under the hood filled with microprocessors, relays,
fuse blocks and sundry sensors reduces "hazard" to accessories
that are powered from the system?
Admittedly, the systems in many vehicles including
aircraft have a lot of bells and whistles that go to
convenience and gee-whiz features at the cost of
ownership and increased complexity (read reduced
reliability). How do they influence rudimentary
performance that goes to risk of death by design flaw?
Just because there are more parts that do more things
does not automatically translate into improvements in
critical performance (reliability).
Your nail gun will become useless if there's no power,
shortage of air, no specialized cartridges of nails, or perhaps
a tiny broken part within. I have hammers that were used
by my grandfather 60+ years ago. They still perform as
designed when new. They also have exceedingly low risk
of failure to perform. If the system in your car is
the new gold-standard for power system design, there has
to be a host of simple-ideas that support the notion.
"Passing muster" is non-specific. What design goals were
honored to craft the system in your Porsche as compared
to design goals honored to craft the electrical systems
in your Lancair?
Check out DC power section of Mil-Std-704F at:
http://www.aeroelectric.com/Reference_Docs/Mil-Specs/Mil-Std-704f.pdf
and tell us how the Porshe system exceeds or expands
on those requirements and what benefit is derived on
behalf of a DO-160 qualified accessory?
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
Message 11
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Subject: | Re: Grounding Of Fuel Senders |
I added these wires to my RV6A (metal tanks) to ground the senders to the main
spar which has a bonding strap to the field of tabs ground bus.
Works fine so far - no adverse effects - will be flying first flight in a couple
of weeks - just got my airworthiness cert.
Ralph Capen
RV6A N822AR 0 hrs
-----Original Message-----
>From: Dave VanLanen <davevanlanen@sbcglobal.net>
>Sent: Dec 12, 2008 11:02 AM
>To: aeroelectric-list@matronics.com
>Subject: AeroElectric-List: Grounding Of Fuel Senders
>
>I am installing VDO fuel senders in the metal fuel tanks of my all-metal kit
>aircraft. These senders do not have a ground lug, and the sender, by
>design, is not isolated from the fuel tank because the mounting screws are
>inserted into a metal mounting ring which is in metal-to-metal contact with
>the inside of the fuel tank. The construction manual calls for grounding
>the sender to the airframe using a wire from the airframe to a ring terminal
>under one of the mounting screws. My concern with this approach is that I
>might inadvertently introduce a "ground loop" into the system by grounding
>in this fashion. I would prefer to isolate the sender from the airframe and
>run a return wire to the universal ground buss on the firewall, but because
>of the design of the sender this would be difficult to do. Has anyone else
>dealt with installation of these senders, and if so, can you offer me any
>advice?
>
>Thanks,
>Dave Van Lanen
>
Message 12
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Subject: | Re: Grounding Of Fuel Senders |
Congratulations on the FAA Cert....... Enjoy that first flight!!!
Tim
----- Original Message -----
From: "Ralph E. Capen" <recapen@earthlink.net>
Sent: Friday, December 12, 2008 9:45 AM
Subject: Re: AeroElectric-List: Grounding Of Fuel Senders
<recapen@earthlink.net>
>
> I added these wires to my RV6A (metal tanks) to ground the senders to the
main spar which has a bonding strap to the field of tabs ground bus.
>
> Works fine so far - no adverse effects - will be flying first flight in a
couple of weeks - just got my airworthiness cert.
>
> Ralph Capen
> RV6A N822AR 0 hrs
>
>
> -----Original Message-----
> >From: Dave VanLanen <davevanlanen@sbcglobal.net>
> >Sent: Dec 12, 2008 11:02 AM
> >To: aeroelectric-list@matronics.com
> >Subject: AeroElectric-List: Grounding Of Fuel Senders
> >
> >I am installing VDO fuel senders in the metal fuel tanks of my all-metal
kit
> >aircraft. These senders do not have a ground lug, and the sender, by
> >design, is not isolated from the fuel tank because the mounting screws
are
> >inserted into a metal mounting ring which is in metal-to-metal contact
with
> >the inside of the fuel tank. The construction manual calls for grounding
> >the sender to the airframe using a wire from the airframe to a ring
terminal
> >under one of the mounting screws. My concern with this approach is that
I
> >might inadvertently introduce a "ground loop" into the system by
grounding
> >in this fashion. I would prefer to isolate the sender from the airframe
and
> >run a return wire to the universal ground buss on the firewall, but
because
> >of the design of the sender this would be difficult to do. Has anyone
else
> >dealt with installation of these senders, and if so, can you offer me any
> >advice?
> >
> >Thanks,
> >Dave Van Lanen
> >
>
>
Message 13
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Subject: | Re: Crimping of machined D-sub pins with 4-Way |
Indent Pin Crimper
Just to close this out. I went ahead and modified the positioner as Bob
describes below. Since my machine shop equipped neighbor was AWOL, I
chucked it up in the drill press and worked it over with a file. Works
perfectly now. A few subtleties in the Eclipse crimpers design now be
come evident, i.e. when the pin is pushed all the way in, there's
effectively a detent which you can feel when inserting the male or
female pin, indicating that everything is in it's proper place for a
good crimp.
So, to repeat, if you have an Eclipse crimper, check the dimension of
the positioner. If it is more than .260" (.302 in my case) as
indicated in Bob's photos below, you can fix it by reducing it to .260".
I picked up my Eclipse from Stein about a year ago but who knows what
vintage it might be.
Thanks again all.
Bill
Robert L. Nuckolls, III wrote:
> <nuckolls.bob@aeroelectric.com>
>
> At 11:33 AM 12/10/2008, you wrote:
>> I think I have several problems and oversights that need to be
>> addressed.
>>
>> I'm using a tool that looks like this:
>> http://aeroelectric.com/Pictures/Tools/Crimp_Tools/rct-3.jpg
>> As you said, it is setup for one size of wire and one type of
>> pin/socket. I've been using it on 20AWG and probably 22 AWG which
>> would immediately indicate some inconsistency. But in this case, I
>> was using it on 24AWG wires that was part of a pre-made harness pig
>> tail.
>>
>> In addition, I was trying to strip the wire just far enough to barely
>> clear or be flush with the pin. Given that this crimper seems to
>> crimp concentrically at the the very tip of the pin, allowing any of
>> the insulation into the pin could further compromise the crimp. (I'm
>> attaching 2 pics of the pin that failed).
>> I first need to determine what size wire the crimper is setup for and
>> limit its use to that wire. And re-confirm I'm using the right pins
>> (non-high density).
>>
>> For this particular connection involving the 24AWG wires, I'm going
>> to follow your guidance on using a 9 pin D-sum with solder terminals
>> along with shrink tubing, clear adhesive and more shrink tubing.
>> It's a good solution for this particular connection.
>>
>> I'll have to take a closer look at the adjustable Daniels crimper if
>> I want to get serious... but it may be too expensive to justify.
>>
>> What do you think?
>
> Thanks for the great pictures. I've added those to my
> reference library. It seems that Eclipse is back to their
> old habits.
>
> When I started stocking that tool many moons ago, I
> discovered that the pin-positioner was cut wrong
> allowing the pin to set too deep in the tool. This
> causes the crimp to happen too far back on the wire
> grip as shown here . . .
>
> http://aeroelectric.com/Pictures/Tools/Crimp_Tools/4-Quad/Positioner_Mod_0.jpg
>
>
> I used to check every tool and modify as shown
> here . . .
>
> http://aeroelectric.com/Pictures/Tools/Crimp_Tools/4-Quad/Positioner_Mod_1.jpg
>
>
> I put every positioner in the lathe and cut it back
> on the pin-entry end to achieve the dimension shown.
> This moved the pin up in the too such that the
> wire-grip was just flush to slightly under-flush
> with the face of the tool.
>
> B&C checked the tools too after I turned that
> activity over to them. Tim reported to me some
> months later that the pin-positioners were coming
> in okay. I figured that it was the result of a
> letter I wrote to Eclipse citing the problem.
>
> The other part of your problem is putting 24AWG wires
> into a 20/22 AWG pin. The tool is designed to have a slightly
> over-crimp on 20AWG and slightly under-crimp on 22AWG.
> This means it's way under-crimped for 24AWG. You fix this
> by striping 24AWG wire 2X length for exposed strands and
> fold the strands back to double the amount of copper
> in the finished joint.
>
> Alternatively, your idea of a fixed "plug" in the
> bottom of the pin-positioner works too but you
> have to be VERY careful about too much plug . . .
> it can be hard to get out. You can use a small
> twist drill to clear the hole.
>
> Bob . . .
Message 14
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Subject: | Re: Grounding Of Fuel Senders |
At 10:02 AM 12/12/2008, you wrote:
>I am installing VDO fuel senders in the metal fuel tanks of my
>all-metal kit aircraft. These senders do not have a ground lug, and
>the sender, by design, is not isolated from the fuel tank because
>the mounting screws are inserted into a metal mounting ring which is
>in metal-to-metal contact with the inside of the fuel tank. The
>construction manual calls for grounding the sender to the airframe
>using a wire from the airframe to a ring terminal under one of the
>mounting screws. My concern with this approach is that I might
>inadvertently introduce a "ground loop" into the system by grounding
>in this fashion. I would prefer to isolate the sender from the
>airframe and run a return wire to the universal ground buss on the
>firewall, but because of the design of the sender this would be
>difficult to do. Has anyone else dealt with installation of these
>senders, and if so, can you offer me any advice?
Metal tanks in a metal airplane will provide sufficient
ground for these senders to work as advertised. Adding
the wire as directed in the instructions will not hurt
anything either. Go ahead and install the requested wire
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
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