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Compass adjustment

BritishCubBloke

SPONSOR
Bellingen, NSW, Australia
Have just put a new compass in the panel. The deviation is horrible. Trying it out it doesn't seem to be any good anywhere where it might go. Does anyone know how to do the tricks with little magnets to get it vaguely in the ballpark?
 
Thanks. The deviation is so horrible (60-90 degrees in some orientations) that I don't think twiddling the little screws will do it. Just wondering if anyone has experience of using extrenal compensatory magnets to bring things roughly back into reality.
 
I have a SIRS PEGASUS which I'm told works better than most. But after trying several spots on the panel, installed it as far left as possible to get it away from the electric turn and bank that played hell with it. It too has horrible deviation but I sware that it is getting better the longer it is in the panel. I had this same experiance with my Cessna 120 -- as time went on the compass seemed to get closer to the truth --- I know this sounds farfetched but I am two for two on this experience.
The current location on the panel puts the compass fairly close to the pulselite power supply (mounted up under the panel) -- kind of fun to watch the compass set there telling pretty much the truth, turn the Pulselite on and watch the compass turn 180 degrees.
 
Keep it FAR away from the swinging magnets in your tach.
 
...horrible deviation but I sware that it is getting better the longer it is in the panel. I had this same experiance with my Cessna 120 -- as time went on the compass seemed to get closer to the truth ---

see... ya demagnetize something metal by hitting/rapping it hard....

now can we talk about those landings ;-) ;-)
 
Thanks everybody. The moral of the tale is: "Use the 'search'!"

It's very reassuring to know that no-one's compass works! Sets my expectations.
 
I've tried to route my wiring such that it is level and at the same height as the compass, with the idea of having the magnetic field vertical at the compass location. We'll see if it's any good - - Anybody else do this, with success or lack of success??
 
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I've tried to route my wiring such that it is level and at the same height as the compass, with the idea of having the magnetic field vertical at the compass location. We'll see if it's any good - - Anybody else do this, with success or lack of success??
Mount the compass in the middle of the upper windshield.

Sent from my SAMSUNG-SM-G900A using SuperCub.Org mobile app
 
Note the date, 2011. The original installation in the panel was great for a while, but it significantly degraded over time and I had to move it. Upper left windshield ended up being the best, but I expect every installation is a little different.
 
Note worthy is that in my experimental Super Cub I have a Dynon D10A with the remote magnetometer, it's sort of mind boggling how well it works with almost no deviation. I dare say it works perfectly. Noticed that the XCUB has the Vertical compass card located in a very piper like traditional location- the upper windshield.
 
Mount the compass in the middle of the upper windshield.

Sent from my SAMSUNG-SM-G900A using SuperCub.Org mobile app

I know of a Cub with a “SIRS Navigator” . The compass is mounted on an aluminum plate attached to overhead cross member. The plate forms about 5 inches forward to the curve of the windshield, and holds the compas which folds up out of the way (feature never needed). Perfectly accurate.
 
I suggest degaussing using any old elecromagnet.Remove the compass and slide the electromagnet slowly up and down the V bars for a few minutes.Works a charm.Have solved several cub compass swinging problems this way.
 
X2 top of windshield. Vertical card read, custom bracket to give max clearance from tube fuselage. When I rewired cubby, I tried like heck to get mine to “ballpark” in the panel, but couldn’t make the compass happy there...
 
I seriously doubt you’ll get a magnetic compass to swing mounted in the panel of a Cub with an electrical system......or maybe even one without.

That said, the SIRS compasses seem to work when mounted high in the windshield of many airplanes.

But mount a Compass right next to electrical equipment, and where do you THINK it will point?

MTV
 
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