---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Wed 04/25/18: 10 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 01:44 AM - Degaussing (tshort) 2. 02:22 AM - Re: Degaussing (John Cox) 3. 05:52 AM - Re: Degaussing (user9253) 4. 06:35 AM - Re: Degaussing (FLYaDIVE) 5. 06:36 AM - Re: Re: Degaussing (FLYaDIVE) 6. 06:40 AM - Re: Magic stuff . . . (Alec Myers) 7. 06:53 AM - Re: Magic stuff . . . (Kelly McMullen) 8. 12:37 PM - Re: Re: Degaussing (Robert L. Nuckolls, III) 9. 12:51 PM - Re: Degaussing (David Lloyd) 10. 07:51 PM - Re: Degaussing (Robert L. Nuckolls, III) ________________________________ Message 1 _____________________________________ Time: 01:44:57 AM PST US Subject: AeroElectric-List: Degaussing From: "tshort" The aft mounted magnetometer in my RV 10 has failed interference testing, only when the rudder moves. Garmin tells me I need to degauss the rudder cables. Anyone have suggestions on how to do so? Read this topic online here: http://forums.matronics.com/viewtopic.php?p=479541#479541 ________________________________ Message 2 _____________________________________ Time: 02:22:12 AM PST US From: John Cox Subject: Re: AeroElectric-List: Degaussing Start with a simple (Free)Android phone app Such as Gauss Meter by Keuwlsoft. It will help locate or confirm the item that becomes mangetized. A degauss process is a coil of wire which creates a demagnetize field when switched on. They were commonly used by TV techs in the 60s -70s to remove interference in Cathode Ray color picture tubes back in the day. John Cox On Wed, Apr 25, 2018, 01:50 tshort wrote: > > The aft mounted magnetometer in my RV 10 has failed interference testing, > only when the rudder moves. > > Garmin tells me I need to degauss the rudder cables. > > Anyone have suggestions on how to do so? > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=479541#479541 > > ________________________________ Message 3 _____________________________________ Time: 05:52:54 AM PST US Subject: AeroElectric-List: Re: Degaussing From: "user9253" Try a soldering gun (NOT a soldering iron). Remove the two screws that hold the heating element. Put the heating element around the rudder cable and reassemble the soldering gun. Turn on the soldering gun and slowly move it along the rudder cable, being careful not to burn yourself or anything else. I have never done this and have never heard about others doing it. But hey, it is worth a try. -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=479544#479544 ________________________________ Message 4 _____________________________________ Time: 06:35:17 AM PST US From: FLYaDIVE Subject: Re: AeroElectric-List: Degaussing Hello Shorty: Very Interesting! In the good old days it was very easy to make a Degaussing Coil (D-C), actually the coil was already made for you and all you had to do was hook up 110 VAC. The Coil was the DEFLECTION COIL on the back of the old TV's... It is the large coil that slipped over the shank of the CRT... Cathode Ray Tube. All that a D-C is, is a very long length of a coil of wire. To the ends of the coil you apply 110 VAC through a PUSH BUTTON switch. It continuously reverses the magnetic fields at the rate of 60 times per second (60 Hz). The coil is then slowly moved in ONE DIRECTION along the length of the item you wish to demagnetize. OK, lets prove the cables are magnetized. I doubt it! Why? Because the cable are made of a low ferrous metal. The cables are advertised as Stainless Steel (S/S). True, not all S/S is non-magnetic. Start with a COMPASS - Move the compass along the length of the cables and of course the STEEL pivot points. The Compass will point directly to the magnetized item. Sounds like you are installing a G5 system? ALSO... Go back and watch your DG/HSI as you move the rudder peddles. The Heading should change as the peddles are moved. Move them slowly from stop to stop. My SWAG is: If the Heading does NOT change - Don't worry about it, you are good to go! The test procedure is way more sensitive/selective than the Magnetometer and the DG/HSI. If the DG/HSI does move then YES - Use the D-C. Side Note: You can also do as ships do: Fly a course in direct Opposition to the magnetic fields of the earth. This is used to Degauss the ship... in your case the plane (ship). Look up Ship Degaussing procedures - Check out "The Chapman's Manual". Since there are very few old TV's which you can steal a coil from let's move to your next options. 1 - Look for a place where you can purchase or rent a D-C. Look at the old electronic shops. 2 - Obtain a ROLL of INSULATED wire - 24 to 34 AWG about 1,000 Ft. You will have to have access to BOTH ends of the wire. Then all you have to do connect a 110 VAC line and a Push Button Switch to the ends. The go GAUSS! Best of luck, Barry On Wed, Apr 25, 2018 at 4:44 AM, tshort wrote: > > The aft mounted magnetometer in my RV 10 has failed interference testing, > only when the rudder moves. > > Garmin tells me I need to degauss the rudder cables. > > Anyone have suggestions on how to do so? > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=479541#479541 > > ________________________________ Message 5 _____________________________________ Time: 06:36:18 AM PST US From: FLYaDIVE Subject: Re: AeroElectric-List: Re: Degaussing WOW! GREAT TRICK JOE!!! GREAT TRICK! Barry On Wed, Apr 25, 2018 at 8:52 AM, user9253 wrote: > > Try a soldering gun (NOT a soldering iron). Remove the two screws that > hold the heating element. Put the heating element around the rudder cable > and reassemble the soldering gun. Turn on the soldering gun and slowly > move it along the rudder cable, being careful not to burn yourself or > anything else. > I have never done this and have never heard about others doing it. But > hey, it is worth a try. > > -------- > Joe Gores > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=479544#479544 > > ________________________________ Message 6 _____________________________________ Time: 06:40:12 AM PST US From: Alec Myers Subject: Re: AeroElectric-List: Magic stuff . . . Thanks Bob! I shall continue with my present practice of carefully NOT spraying WD40 into every switch annually. On Apr 24, 2018, at 11:13 PM, Robert L. Nuckolls, III wrote: At 07:12 PM 4/24/2018, you wrote: > > I lost track of which Bob was recommending annual WD-40 as a switch failure preventive prophylactic, and which Bob wasnt. > Can someone advise? The short answer is "no". The longer answer is, check the engineering data on any line of switches or relays you might be considering for your project. You will find a constellation of styles and ratings. It will be a rare switch or relay that is rated for less than TENS OF THOUSANDS of operations at rated load. Now, consider how heavily you are going to load this device . . . pushing the ratings? Probably not. So from an ELECTRICAL perspective, the service life of this devices will be some factor greater than rated. Then we consider mechanical service life . . . which logically exceeds the rated electrical service life. Now, how many operations are you going to put on this device every year? Based on your anticipated service demands, how many flight hours will you put on the switch before it's at risk for end of life? Trust me, it's a BIG number . . . so big in fact that and end of life failure is exceedingly tiny if not zero. You cannot wear out that device during your life experience with the airplane. Hmmmm . . . switches and relays get replaced all the time. Yup . . . and probably for reasons unrelated to actual operating cycles on the device. Okay, what's the reason for premature failure? It's probably a combination of serval things . . . most of which you'll have no control over. Hmmmm . . . what's a poor owner operator to do? Can't tell you without going through the kinds of failure analysis that dominated the last 10 years of my career in GA. The analysis was expensive, time consuming and seldom revealed a cheap and dirty resolution. Some failures were one-of events usually based on some fabrication error . . . it took 5-6 weeks of pushing one poor customer's airplane up the chain of time, talent and resources before I talked the pilots into letting me tape a 37 conductor ribbon cable to the fuselage and past gaskets in the baggage and passenger doors. With this rig I was able to watch a constellation of parameters in the tail while we climbed to 41000 feet . . . one more time . . . in search of the elusive failure. Found a crimp pin in a pressure bulkhead feed through that was not seated. The wire bundles had to get cold and shrink enough to pull the pin back and cause the failure to manifest. That 10-cent error cost tens of thousands to chase down. What's this have to do with switches on your panel? It's but one example of how root cause for a mis-behavior can run the range from observable broken wires, dripping water or hydraulic fluid, temperature cycles combined with ozone concentrations, . . . all the way up to failures that would only manifest at altitude after consuming about as much fuel in one flight as my wife's Saturn consumed in a year. Go back and look at the engineering data for the device. I've never seen a manufacturer recommend any form of periodic maintenance . . . much less squirt 'magic stuff' into the device's cracks with some notion of improving service life or, worse yet, 'refurbishing' a misbehaving switch. Back in the day, we had several cans of cleaners, lubes, sealers, etc. on the workbench where we repaired radio and television sets. It was always gratifying to drive the mischief out of a rotary switch, noisy volume control or arcing flyback transformer with a squirt of magic stuff. But we're talking about airplanes now. We're talking about devices that have obviously failed to meet service life predictions. Okay, now what? What forces in physics are responsible? Will 'magic stuff' mitigate those forces . . . probably not. Will they 'repair' the effects or simply squeeze a few more operations out of a device that is close to gross failure? Finally, how do you KNOW that you've squirted the magic stuff into the RIGHT location and that it doesn't present a new hazard to functionality if it gets into the WRONG location. Finally, how hard is it to replace a $5 switch that's held on the panel with one nut and wired with a couple or three fast-ons? I used to recommend that my seminar attendees take a sunny afternoon and $50 worth of switches and replace everything on the panel . . . just for the hell of it. System reliability benefits far more from preventative maintenance than it does from magic stuff applied to a device that's already begging for help. One more example. One day at Beech, a sales rep came out to pitch a particular kind of magic stuff. I think it was called "Stabilant 22." It was reputed, nay, demonstrated to improve the quality of metallic connection between pins and sockets in our harness connectors. So, we piled engineering data, test reports, user testimonials, etc. etc. against field service experience on a fleet of thousands of airplanes gathered over 50+ years. Yeah, Stabilant 22 was pretty whippy stuff . . . but expensive and labor intensive with a risk for waste due to spillage and getting it on the wrong surfaces. I could just see the faces of our line techs when we handed each one a bottle of magic stuff with a requirement to properly apply to each connector before it was mated up. Then, there was the question, what's the return on investment? After some consideration, we deduced that it was a 'fix' for a problem we didn't have. So there your have the long answer. If any combination of components on your airplane is crying out for help, then replace on condition is the lowest risk and probably the lowest cost approach to risk management. WD40 is good for the kid's tricycle that might sit out and get rained on from time to time. Bob . . . ________________________________ Message 7 _____________________________________ Time: 06:53:45 AM PST US Subject: Re: AeroElectric-List: Magic stuff . . . From: Kelly McMullen Another side to the issue. WD-40 is essentially fish oil or a synthetic clone of fish oil. It dries up over time and leaves a very sticky mess, as well as attracting dirt. If you insist on lubricating connections, ACF-50 or Corrosion X or just contact cleaner are better alternatives. The only use I have found for WD-40 around an airplane that doesn't cause future problems is to use it as a belly cleaning solution. Kelly On 4/25/2018 6:38 AM, Alec Myers wrote: > > Thanks Bob! I shall continue with my present practice of carefully NOT spraying WD40 into every switch annually. > >> I lost track of which Bob was recommending annual WD-40 as a switch failure preventive prophylactic, and which Bob wasnt. >> Can someone advise? > > The short answer is "no". ________________________________ Message 8 _____________________________________ Time: 12:37:59 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Re: Degaussing Try a soldering gun (NOT a soldering iron). Remove the two screws that hold the heating element. Put the heating element around the rudder cable and reassemble the soldering gun. Turn on the soldering gun and slowly move it along the rudder cable, being careful not to burn yourself or anything else. I have never done this and have never heard about others doing it. But hey, it is worth a try. It works. I've used the soldering gun to demag small tools. There are several articles on the 'net for doing similar tasks. demagnitizer from old soldering gun.jpg Here the author made up a coil of longer wire (gives stronger field with less heating). One could take a piece of bare 12AWG copper and form it 4-5 turns around the target material before reconnecting to the soldering gun. I've measured the current in stock Weller tips at over 200 amps. So using the single-turn of a stock tip would give you 200+ ampere-turns of flux. Fabricated coils will be higher resistance but if you can get 150A through 5 turns, your degaussing flux rises to 750AT. Bob . . . ________________________________ Message 9 _____________________________________ Time: 12:51:05 PM PST US From: "David Lloyd" Subject: Re: AeroElectric-List: Degaussing =2E . . any chance there is other electronics "back" there that are operati onal, such as tail strobe and power supply causing interference with flux.. ?? --------------------------------------------------------------------------- ----- ----- Original Message ----- Sent: Wednesday, April 25, 2018 6:33 AM Subject: Re: AeroElectric-List: Degaussing Hello Shorty: Very Interesting! In the good old days it was very easy to make a Degaussing Coil (D-C), ac tually the coil was already made for you and all you had to do was hook up 110 VAC. The Coil was the DEFLECTION COIL on the back of the old TV's... It is th e large coil that slipped over the shank of the CRT... Cathode Ray Tube. All that a D-C is, is a very long length of a coil of wire. To the ends of the coil you apply 110 VAC through a PUSH BUTTON switch. It continuousl y reverses the magnetic fields at the rate of 60 times per second (60 Hz). The coil is then slowly moved in ONE DIRECTION along the length of the ite m you wish to demagnetize. OK, lets prove the cables are magnetized. I doubt it! Why? Because the cable are made of a low ferrous metal. The cables are advertised as Stain less Steel (S/S). True, not all S/S is non-magnetic. Start with a COMPASS - Move the compass along the length of the cables an d of course the STEEL pivot points. The Compass will point directly to the magnetized item. Sounds like you are installing a G5 system? ALSO... Go back and watch your DG/HSI as you move the rudder peddles. T he Heading should change as the peddles are moved. Move them slowly from s top to stop. My SWAG is: If the Heading does NOT change - Don't worry abo ut it, you are good to go! The test procedure is way more sensitive/select ive than the Magnetometer and the DG/HSI. If the DG/HSI does move then YES - Use the D-C. Side Note: You can also do as ships do: Fly a course in direct Oppositi on to the magnetic fields of the earth. This is used to Degauss the ship.. =2E in your case the plane (ship). Look up Ship Degaussing procedures - C heck out "The Chapman's Manual". Since there are very few old TV's which you can steal a coil from let's m ove to your next options. 1 - Look for a place where you can purchase or rent a D-C. Look at the o ld electronic shops. 2 - Obtain a ROLL of INSULATED wire - 24 to 34 AWG about 1,000 Ft. You w ill have to have access to BOTH ends of the wire. Then all you have to do connect a 110 VAC line and a Push Button Switch to the ends. The go GAUSS! Best of luck, Barry On Wed, Apr 25, 2018 at 4:44 AM, tshort wrote: The aft mounted magnetometer in my RV 10 has failed interference testin g, only when the rudder moves. Garmin tells me I need to degauss the rudder cables. Anyone have suggestions on how to do so? --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ________________________________ Message 10 ____________________________________ Time: 07:51:55 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Degaussing At 02:49 PM 4/25/2018, you wrote: >=EF=BB >. . . any chance there is other electronics >"back" there that are operational, such as tail >strobe and power supply causing interference with flux..?? Excellent question. I am skeptical of the notion that control cables have become magnetized . . . and if they were, they would have to carry flux lines longitudinally . . . i.e. little to no discernable changes in magnetic field as the cables operate to affect rudder position. But if moving the rudder has an observable effect, then there has to be a foundation in physics for the observation. On the other hand, does it matter? If the magnetic compass feature is 'swung' with the rudder centered . . . what is the probability of introducing a critical error into the system's magnetic nav data with a large rudder excursion? Most autonomous attitude tracking involves very small excursions of flight controls. If rudder motion was a source of error, just how often and under what conditions would that error manifest? Bob . . . ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message aeroelectric-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/AeroElectric-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/aeroelectric-list Browse Digests http://www.matronics.com/digest/aeroelectric-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.