---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Thu 09/22/05: 16 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 12:25 AM - KT-76 Connector () 2. 01:00 AM - Re: 80 Amp Shunt () 3. 05:53 AM - Re: Re: 80 Amp Shunt (Robert L. Nuckolls, III) 4. 06:27 AM - Re: 80 Amp Shunt (Christopher Stone) 5. 06:44 AM - Re: Wire selection (Ernest Christley) 6. 07:38 AM - Re: Re: Wire selection (Robert L. Nuckolls, III) 7. 07:52 AM - HHK MAX fuse holder and 6AWG wire splicing (Robert L. Nuckolls, III) 8. 07:52 AM - Re: 80 Amp Shunt (Eric M. Jones) 9. 08:14 AM - Cage horizon when powering up ? (Gilles Thesee) 10. 08:26 AM - Re: Re: Wire selection (Stein Bruch) 11. 09:23 AM - Re: Re: Wire selection (B Tomm) 12. 11:04 AM - Re: Cage horizon when powering up ? (Robert L. Nuckolls, III) 13. 12:48 PM - Re: Cage horizon when powering up ? (Gilles Thesee) 14. 01:01 PM - Re: Cage horizon when powering up ? (Leo Corbalis) 15. 08:16 PM - Re: Cage horizon when powering up ? (Robert G. Wright) 16. 11:47 PM - Re: Re: degaussing (demagnetizing) my roll bar (owner-aeroelectric-list-server@matronics.com) ________________________________ Message 1 _____________________________________ Time: 12:25:28 AM PST US From: Subject: AeroElectric-List: KT-76 Connector --> AeroElectric-List message posted by: The connector for the KT-76 is available from Mouser Electronics. It is the same connector used on the Narco MK12D, and the PS Engineering audio panels as well as others. Best to check before ordering as the Narco AT50/50A/155/165 transponders use different pins. Compare the diagram to your connector. Connector is 538-09-50-6125 $0.79 Terminal pins 538-08-05-0302 $0.28 John Lundberg Los Angeles, CA ________________________________ Message 2 _____________________________________ Time: 01:00:04 AM PST US From: Subject: AeroElectric-List: Re: 80 Amp Shunt --> AeroElectric-List message posted by: shunts of all amp ratings http://www.deltecco.com/indexpage.html OR http://www.cshunt.com/pdf/la.pdf Time: 11:54:49 PM PST US From: Subject: AeroElectric-List: 80 Amp Shunt --> AeroElectric-List message posted by: Does anyone know where to buy a 80amp/50mv shunt for an Electronics International volt/amp meter. I bought a used digital meter at Oshkosh and it did not have the shunt. I have found 50 and 75 amp from a marine supply but not the 80 amp version. Thanks. John Lundberg Los Angeles, cA --------------------------------- Click here to donate to the Hurricane Katrina relief effort. ________________________________ Message 3 _____________________________________ Time: 05:53:24 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Re: 80 Amp Shunt --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 12:58 AM 9/22/2005 -0700, you wrote: >--> AeroElectric-List message posted by: > >shunts of all amp ratings http://www.deltecco.com/indexpage.html > >OR http://www.cshunt.com/pdf/la.pdf > > >Time: 11:54:49 PM PST US >From: >Subject: AeroElectric-List: 80 Amp Shunt > >--> AeroElectric-List message posted by: > >Does anyone know where to buy a 80amp/50mv shunt for an Electronics >International >volt/amp meter. I bought a used digital meter at Oshkosh and it did not have >the shunt. I have found 50 and 75 amp from a marine supply but not the 80 >amp version. Do I presume correctly that the instrument is intended to read 0-100% as a loadmeter? I.e., 50mv = 100 on instrument? If so, then sizing the shunt to the alternator is the appropriate thing to do. 80A is a bit of an odd size but shunt fab shops can built to suit. If you can find a shunt just over 80A, like 100A, it's easy to re-calibrate it by cutting down the shunt element with a file. I can do it for you if you can't find an exact 80. Also, you could consider using the 75A shunt . . . it would simply "derate" your alternator by 5A. It's doubtful that you'll ever need to know what the loads are up so close to the top end of the alternator's capability. Bob . . . ________________________________ Message 4 _____________________________________ Time: 06:27:50 AM PST US From: Christopher Stone Subject: Re: AeroElectric-List: 80 Amp Shunt --> AeroElectric-List message posted by: Christopher Stone Shunts... B&C has them. http://www.bandcspecialty.com/parts.html cs -----Original Message----- From: jlundberg@cox.net Subject: AeroElectric-List: 80 Amp Shunt --> AeroElectric-List message posted by: Does anyone know where to buy a 80amp/50mv shunt for an Electronics International volt/amp meter. I bought a used digital meter at Oshkosh and it did not have the shunt. I have found 50 and 75 amp from a marine supply but not the 80 amp version. Thanks. John Lundberg Los Angeles, cA ________________________________ Message 5 _____________________________________ Time: 06:44:02 AM PST US From: Ernest Christley Subject: AeroElectric-List: Re: Wire selection --> AeroElectric-List message posted by: Ernest Christley Ok, multiple strands to increase capacity is not applicable to light aircraft. I can easily see the safety issues. I also agree that 18AWG for the "bird's nest behind the panel" would make for a difficult work environment. I'll need to drop down to 22AWG for most of that. Furthermore, I agree that using a multistranded cable will increase weight somewhat. I believe the weight is offset by the safety of an additional jacket for the wire, the clean look of the installation, and the simplicity of running the wire. It is just easier to make a cable go where you want it to, vs several individual wires that you just spent hours tying together. Someone mentioned cost. The cable I'd like to have would be more expensive, but not significantly so. If you count the time tying together individual wires, the cable could be considered cheaper. But, all told, I don't see enough of a difference to really make an argument either way. So, Stenair has a fine selection of aircraft wire and cable in all sorts of multi-colored goodness. But their cable is only available in 22AWG. Does anyone have a source of aircraft wire with a greater selection? -- ,|"|"|, | ----===<{{(oQo)}}>===---- Dyke Delta | o| d |o www.ernest.isa-geek.org | ________________________________ Message 6 _____________________________________ Time: 07:38:15 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Re: Wire selection --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 09:42 AM 9/22/2005 -0400, you wrote: >--> AeroElectric-List message posted by: Ernest Christley > > >Ok, multiple strands to increase capacity is not applicable to light >aircraft. I can easily see the safety issues. > >I also agree that 18AWG for the "bird's nest behind the panel" would >make for a difficult work environment. I'll need to drop down to 22AWG >for most of that. > >Furthermore, I agree that using a multistranded cable will increase >weight somewhat. I believe the weight is offset by the safety of an >additional jacket for the wire, the clean look of the installation, and >the simplicity of running the wire. It is just easier to make a cable >go where you want it to, vs several individual wires that you just spent >hours tying together. > >Someone mentioned cost. The cable I'd like to have would be more >expensive, but not significantly so. If you count the time tying >together individual wires, the cable could be considered cheaper. But, >all told, I don't see enough of a difference to really make an argument >either way. > >So, Stenair has a fine selection of aircraft wire and cable in all sorts >of multi-colored goodness. But their cable is only available in 22AWG. >Does anyone have a source of aircraft wire with a greater selection? I've been following this thread and the majority of the simple-ideas and deductions made therefrom have been sound and correct. I'll offer the following enlargements to the discussion. While arrays of smaller wires might seem to reject heat better than a single large wire of the same cross-section, there are bundling effects that tend to wash away all the advantages with respect to heat rejection. Some of you may recall an experiment I illustrated some months ago wherein the question was, "How much current does it take to chase the smoke out of a 22AWG wire?" In the photo at http://www.aeroelectric.com/Pictures/20A_22AWG.jpg There's a 22AWG Tefzel wire with tiny thermocouple attached and strung out in free air. At the time I took the picture, the wire had been loaded to 20A for several minutes. No smoke. In fact, I don't think the wire had reached operating limits for Tefzel even yet. I tried to go higher in current but the 120 line to my shop was inadequate to the task of supporting my largest bench supply . . . I need to run in a 240 line to finish the experiment. Given what I've demonstrated above, it seems really strange that in some cases, 22AWG wire is de-rated to 3A max continuous in bundles where the majority of wires are also loaded to the hi side of their max rating. Just keep in mind that wires are rated based on temperature limits of the insulation and the ability of the wire, as installed, to reject heat. You're almost never in danger of burning a wire due to low duty cycle overloads several times the wire chart rating for any given application. The breaker opens long before the wire is really at-risk for damage. Fuses open even faster. In the aircraft business, pre-bundled wires are used only where essential. Twisted pairs, trios, and/or to add shielding, etc. The economics of using pre-bundled wires has been researched dozens of times over the years and found to be very limited in applicability and never cost effective over the building of specific bundles of single strands of wire when twisting or shielding was not necessary. If one is desirous of improving the looks of an installation by the use of pre-bundled wires, just keep in mind that the $time$ you spend achieving this appearance is $time$ that's no longer available to push other details of your project forward. I've had people write and tell me they were dropping of the List because if they'd spend the same $time$ working on sheet metal and rivets as they have expended on sifting all that interesting "sand" on the List, they'd be much further along. Bob . . . ________________________________ Message 7 _____________________________________ Time: 07:52:12 AM PST US From: "Robert L. Nuckolls, III" Subject: AeroElectric-List: HHK MAX fuse holder and 6AWG wire splicing --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" A few days ago I promised a comic book on wire splicing in general and specifically, using the HHK in-line fuse holder for the MAX series fuses. http://www.aeroelectric.com/Mfgr_Data/Fuses_and_Current_Limiters/Bussman/MAX_InLine.pdf http://www.aeroelectric.com/Mfgr_Data/Fuses_and_Current_Limiters/Bussman/maxifuse.pdf I used to get these holders for about $10 at the local parts stores. I visited 5 stores and nobody has them any more. They're a low volume item and nobody wants to keep them on the pegs. The best price I've found for the HHK was from Mouser at about $12 each. I've ordered a couple to use in my comic book. So, it will be a few days longer but I'm still planning on getting it published. Bob . . . ________________________________ Message 8 _____________________________________ Time: 07:52:29 AM PST US From: "Eric M. Jones" Subject: AeroElectric-List: Re: 80 Amp Shunt --> AeroElectric-List message posted by: "Eric M. Jones" --> AeroElectric-List message posted by: >Does anyone know where to buy a 80amp/50mv shunt for an Electronics >International >volt/amp meter. I bought a used digital meter at Oshkosh and it did not >have >the shunt. I have found 50 and 75 amp from a marine supply but not the 80 >amp version. Thanks. John Lundberg Los Angeles, CA Bob is right, you could get away with something close. But if you wanted to use the 75A/50mV shunt, converting it to an 80A/50mV shunt is easy. Calculations: 50mV / 80A = 0.625 milliOhms=Rt. (the shunt you need). 50mV / 75A = 0.625 milliOhms=Rq (the shunt you can get). Rp=resistor to be put in parallel with the 75A Rq shunt to equal Rt, the shunt you need. Rt= 1/Rp+1/Rq (watch those p's and q's....math humor) Rp=10.1524390 milliOhms.....more math humor, this stuff cracks me up! Okay just use a 10 milliOhm resistor in parallel with the 75A shunt and you'll be right on the money. Regards, Eric M. Jones www.PerihelionDesign.com 113 Brentwood Drive Southbridge MA 01550-2705 (508) 764-2072 "Mankind faces a cross-roads. One path leads to despair and utter hopelessness. The other, to total extinction. Let us pray we have the wisdom to choose correctly." --Woody Allen ________________________________ Message 9 _____________________________________ Time: 08:14:21 AM PST US From: Gilles Thesee Subject: AeroElectric-List: Cage horizon when powering up ? --> AeroElectric-List message posted by: Gilles Thesee Hi Bob and all, We're using an "always hot" AIM electrical horizon. As soon as the master switch is on the gyros start spinning. A buddy (who is also a test pilo)t advised us to always cage the horizon prior to flipping on the master switch. This is supposed to provide a longer service life. What is your opinion ? Is this advice worth a line in the start up check list, or is it just another hangar tale ? Thanks, Regards, Gilles Thesee Grenoble, France ________________________________ Message 10 ____________________________________ Time: 08:26:26 AM PST US From: "Stein Bruch" Subject: RE: AeroElectric-List: Re: Wire selection --> AeroElectric-List message posted by: "Stein Bruch" Ernest, Couple things. I checked with a few distributors/mfgrs very quickly this morning and like I said before, the cost does increase significantly in multi-stranded cables of AWG18. It appears that for something like 4 conductor AWG18 cable, you can expect to pay between $1.70-$4.00 per foot (depending on where you get it and the specs of the wire). That's over TEN to TWENTY TIMES more expensive than buying the wire individually at around $.15/ft for single conductor. Now about the weight. I couldn't easily find the weight of the multi-condutor cable, but single cables are a pretty good comparision. AWG18 by itself weighs somewhere around 7 lbs per 1K'. AWG18 single conductor shielded weighs somewhere around 16lbs per 1K'. Once again, that's over double. You can expect the 4 conductor to increase, but not linearly. It will weigh a good bit more than just running 4 wires. The protection of the extra coating and shield is pretty much a mute point. If you run your wires through bushings/grommets/etc.., they'll outlast the airframe. As far as "hours spent tying together" bundles....well....not many people actually still tie bundles together. Heck, even the brand new airbuses come from the factory with zip ties now, which are really quick. Next, if you do have multi-strands of wire that need managing, put them in a "snakeskin" or expandable sleeve. It's cheap and you can route them anywhere you want. Your desires are good, and you reasoning is ok, but I'm afraid it's just not what you'll end up doing. I'm afraid you'll find out that in reality, you'll rarely actually run the entire 4 AWG18 cables from point A to point B. You'll certainly want to pick off some of the conductors somewere, and with shielded cable that's basically an impossibility or extremely difficult. The wings might be one of the few spots where this would work, but the fuselage has things placed all over, no matter what kind of plane you're building. I'm not trying to flame you here or be judgemental, just that I've built and worked on a lot of airplanes from Cubs to 747's, and if there is a "better way to build this moustrap", most people would be doing it. Homebuilders are an ingenious group, and if something was easier and cheaper, they'd do it. Not to mention I'm about the laziest guy out there, and like others I'm always looking for a way to save time. I'm afraid this just isn't one of those areas. Anyway, if you do decide to move forward with this I won't chastise you, I'll be glad to support you and help you out in any way I can. That being said, I don't know of many retail outlets that have that AWG18 4 conductor wire available, and most of the distributors want you to buy at least 1,000 feet of it to stay in the cheaper price ranges. If you want a decent sized quantity (over 500'), I can help you find it and will be glad to do so even given my personal thoughts on the situation. Have a great week, Stein. -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com]On Behalf Of Ernest Christley Subject: AeroElectric-List: Re: Wire selection --> AeroElectric-List message posted by: Ernest Christley Ok, multiple strands to increase capacity is not applicable to light aircraft. I can easily see the safety issues. I also agree that 18AWG for the "bird's nest behind the panel" would make for a difficult work environment. I'll need to drop down to 22AWG for most of that. Furthermore, I agree that using a multistranded cable will increase weight somewhat. I believe the weight is offset by the safety of an additional jacket for the wire, the clean look of the installation, and the simplicity of running the wire. It is just easier to make a cable go where you want it to, vs several individual wires that you just spent hours tying together. Someone mentioned cost. The cable I'd like to have would be more expensive, but not significantly so. If you count the time tying together individual wires, the cable could be considered cheaper. But, all told, I don't see enough of a difference to really make an argument either way. So, Stenair has a fine selection of aircraft wire and cable in all sorts of multi-colored goodness. But their cable is only available in 22AWG. Does anyone have a source of aircraft wire with a greater selection? -- ,|"|"|, | ----===<{{(oQo)}}>===---- Dyke Delta | o| d |o www.ernest.isa-geek.org | ________________________________ Message 11 ____________________________________ Time: 09:23:45 AM PST US From: "B Tomm" Subject: RE: AeroElectric-List: Re: Wire selection --> AeroElectric-List message posted by: "B Tomm" Steinair HAS pretty much any gauge of wire you will need. They are great to deal with too. Bevan RV7A fuse/finish/wiring/plumbing.... -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Ernest Christley Subject: AeroElectric-List: Re: Wire selection --> AeroElectric-List message posted by: Ernest Christley --> Ok, multiple strands to increase capacity is not applicable to light aircraft. I can easily see the safety issues. I also agree that 18AWG for the "bird's nest behind the panel" would make for a difficult work environment. I'll need to drop down to 22AWG for most of that. Furthermore, I agree that using a multistranded cable will increase weight somewhat. I believe the weight is offset by the safety of an additional jacket for the wire, the clean look of the installation, and the simplicity of running the wire. It is just easier to make a cable go where you want it to, vs several individual wires that you just spent hours tying together. Someone mentioned cost. The cable I'd like to have would be more expensive, but not significantly so. If you count the time tying together individual wires, the cable could be considered cheaper. But, all told, I don't see enough of a difference to really make an argument either way. So, Stenair has a fine selection of aircraft wire and cable in all sorts of multi-colored goodness. But their cable is only available in 22AWG. Does anyone have a source of aircraft wire with a greater selection? -- ,|"|"|, | ----===<{{(oQo)}}>===---- Dyke Delta | o| d |o www.ernest.isa-geek.org | ________________________________ Message 12 ____________________________________ Time: 11:04:11 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Cage horizon when powering up ? --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 05:13 PM 9/22/2005 +0200, you wrote: >--> AeroElectric-List message posted by: Gilles Thesee > > >Hi Bob and all, > >We're using an "always hot" AIM electrical horizon. As soon as the >master switch is on the gyros start spinning. >A buddy (who is also a test pilo)t advised us to always cage the horizon >prior to flipping on the master switch. This is supposed to provide a >longer service life. >What is your opinion ? Is this advice worth a line in the start up check >list, or is it just another hangar tale ? > >Thanks, >Regards, I've not heard this before. I'll call some instrument shops and ask. I had an airplane in my rental fleet where we recommended caging the gyro for parking and uncaging at startup to speed up erection times . . . this was a suggestion of the aircraft's owner. Never did test the premise to see if it made a difference. Was this a new gyro? What does the manufacturer suggest in the installation data? I don't think we've got a single airplane in the club that even offers the manual caging capability. My initial reaction is that it's probably more myth than fact. Bob . . . ________________________________ Message 13 ____________________________________ Time: 12:48:35 PM PST US From: Gilles Thesee Subject: Re: AeroElectric-List: Cage horizon when powering up ? --> AeroElectric-List message posted by: Gilles Thesee > > I've not heard this before. I'll call some instrument shops > and ask. I had an airplane in my rental fleet where we > recommended caging the gyro for parking and uncaging at > startup to speed up erection times . . . this was a suggestion > of the aircraft's owner. Never did test the premise to > see if it made a difference. Was this a new gyro? What does > the manufacturer suggest in the installation data? > > I don't think we've got a single airplane in the club that > even offers the manual caging capability. My initial reaction > is that it's probably more myth than fact. > > Bob, Thank you for responding. I've got the impression that the manual knob is rather for erecting than caging. I believe the rationale behind my buddy's advice is that by erecting the gyro before startup we might relieve the delicate gimbals and gizmos inside. We bought the unit used from a helicopter broker, and it came with only a wiring sheet. I'd be much interested in further advice. Thanks again, Regards, Gilles Thesee Grenoble, France ________________________________ Message 14 ____________________________________ Time: 01:01:59 PM PST US From: "Leo Corbalis" Subject: Re: AeroElectric-List: Cage horizon when powering up ? --> AeroElectric-List message posted by: "Leo Corbalis" We used to cage the old vacuum AH and DG in the Air Force because they would slam against the stops when starting up. The gravity sensing vanes would usually be wide open and with the slow gyro rpm at starting would go wild. The electric ones didn't have a caging knob. Leo Corbalis do not archive ----- Original Message ----- From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Cage horizon when powering up ? > --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" > > > At 05:13 PM 9/22/2005 +0200, you wrote: > >>--> AeroElectric-List message posted by: Gilles Thesee >> >> >>Hi Bob and all, >> >>We're using an "always hot" AIM electrical horizon. As soon as the >>master switch is on the gyros start spinning. >>A buddy (who is also a test pilo)t advised us to always cage the horizon >>prior to flipping on the master switch. This is supposed to provide a >>longer service life. >>What is your opinion ? Is this advice worth a line in the start up check >>list, or is it just another hangar tale ? >> >>Thanks, >>Regards, > > I've not heard this before. I'll call some instrument shops > and ask. I had an airplane in my rental fleet where we > recommended caging the gyro for parking and uncaging at > startup to speed up erection times . . . this was a suggestion > of the aircraft's owner. Never did test the premise to > see if it made a difference. Was this a new gyro? What does > the manufacturer suggest in the installation data? > > I don't think we've got a single airplane in the club that > even offers the manual caging capability. My initial reaction > is that it's probably more myth than fact. > > Bob . . . > > > ________________________________ Message 15 ____________________________________ Time: 08:16:17 PM PST US From: "Robert G. Wright" Subject: RE: AeroElectric-List: Cage horizon when powering up ? --> AeroElectric-List message posted by: "Robert G. Wright" As an Army helicopter pilot in a world of all-electric systems, we have a step to "cage and hold" while we turn on power to our Attitude Indicators (AIs). The explanation is that the electric gyros spin up so much faster than the vacuum systems that caging relieves the system of the drag for the first number of seconds. We've settled on 8-10 seconds of holding the caging knob, after which the AI seems to be pretty stable. Rob Wright RV10 Elevators -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Leo Corbalis Subject: Re: AeroElectric-List: Cage horizon when powering up ? --> AeroElectric-List message posted by: "Leo Corbalis" We used to cage the old vacuum AH and DG in the Air Force because they would slam against the stops when starting up. The gravity sensing vanes would usually be wide open and with the slow gyro rpm at starting would go wild. The electric ones didn't have a caging knob. Leo Corbalis do not archive ----- Original Message ----- From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Cage horizon when powering up ? > --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" > > > At 05:13 PM 9/22/2005 +0200, you wrote: > >>--> AeroElectric-List message posted by: Gilles Thesee >> >> >>Hi Bob and all, >> >>We're using an "always hot" AIM electrical horizon. As soon as the >>master switch is on the gyros start spinning. >>A buddy (who is also a test pilo)t advised us to always cage the horizon >>prior to flipping on the master switch. This is supposed to provide a >>longer service life. >>What is your opinion ? Is this advice worth a line in the start up check >>list, or is it just another hangar tale ? >> >>Thanks, >>Regards, > > I've not heard this before. I'll call some instrument shops > and ask. I had an airplane in my rental fleet where we > recommended caging the gyro for parking and uncaging at > startup to speed up erection times . . . this was a suggestion > of the aircraft's owner. Never did test the premise to > see if it made a difference. Was this a new gyro? What does > the manufacturer suggest in the installation data? > > I don't think we've got a single airplane in the club that > even offers the manual caging capability. My initial reaction > is that it's probably more myth than fact. > > Bob . . . > > > ________________________________ Message 16 ____________________________________ Time: 11:47:01 PM PST US From: owner-aeroelectric-list-server@matronics.com Subject: RE: AeroElectric-List: Re: degaussing (demagnetizing) my roll bar --> AeroElectric-List message posted by: Mickey, I checked my weldments (rollbar and weldment behind pilot - forgot its name) with an old fashioned very cheap needle compass, it does indeed move substantially when close to the welds, and on some other locations. To do this, I needed to be within 1 to 3 inches of the area. A foot from the weldment did not deflect the compass. If you were to hang the compass from the top of the roll bar, I think that you might have an issue, however if you were to use a panel mounted compass, rollbar magnetization would most probably not be an issue. My 2cents. Take care, Michele Delsol RV8 very slow build fuselage > -----Original Message----- > From: owner-aeroelectric-list-server@matronics.com [mailto:owner- > aeroelectric-list-server@matronics.com] On Behalf Of Mickey Coggins > Sent: Friday, September 16, 2005 8:16 PM > To: aeroelectric-list@matronics.com > Subject: Re: AeroElectric-List: Re: degaussing (demagnetizing) my roll bar > > --> AeroElectric-List message posted by: Mickey Coggins matronics@rv8.ch> > > > Eliminating magnetization is a process of scrambling the domains by > > alternating the magnetic field while slowly reducing the field to zero. > A > > spool of wire, and a variable output transformer (variac) are the tools > you > > need; but how much and where is your individual experiment. > > Hi Eric, > > Thanks for the info. Do you think it's a waste of time to do this? > > Thanks, > Mickey > > -- > Mickey Coggins > http://www.rv8.ch/ > #82007 finishing > > > > >