GMU 11 Magnetometer

snoop9erdog · #1 01-11-2021, 11:42 AM

Garmin manuals call out to install the magnetometer with non magnetic tools. Those tools are not easily found.....titanium nut driver, screwdriver, etc. How critical is it that this must be adhered to??

I've mounted the bracket on the wing tip and I'm ready to install and run wires....would literally take me 5 minutes to get er done.....

Desert Rat · #2 01-11-2021, 11:49 AM

I believe you're getting "Non-magnetic" confused with Non-ferrous"

When they say non magnetic tools, they mean (for example) no screwdrivers that use a magnet to hold the bit in place

Raymo · #3 01-11-2021, 11:52 AM

What Terry said. Also, non-ferrous hardware. Brass screws recommended or a high quality stainless. If you test a stainless screw with a magnet, don't use it for the install.

DeeCee 57 · #4 01-11-2021, 11:55 AM

and the same applies to the hardware, non-magnetizable metal screws, nuts and washers. Just use the ones supplied.

snoop9erdog · #5 01-11-2021, 12:08 PM

Ok yes I should have stated no ferrous tools......but nobody has answered the question. What if i do use a normal ferrous tool? a big deal? Does it screw up the magnetometer innerds?

The installation kit comes with all non ferrous hardware already

RV6_flyer · #6 01-11-2021, 12:45 PM

Quote:

Originally Posted by snoop9erdog

Garmin manuals call out to install the magnetometer with non magnetic tools. Those tools are not easily found.....titanium nut driver, screwdriver, etc. How critical is it that this must be adhered to??

I've mounted the bracket on the wing tip and I'm ready to install and run wires....would literally take me 5 minutes to get er done.....

I installed mine 4 or so years ago with standard tools I have in my tool box. USE the hardware that Garmin supplies and it will work perfect.

NO... You do not need special tools to install. Just make sure there is no steel in anything near where you mount it.

mfleming · #7 01-11-2021, 01:39 PM

I'm working on installing my GMU 11 right now.

This is how I deal with the non-magnetic tool issue. For instance I needed to use a #1 Philips...I placed the tip of my #1 into a drawer of very light washers, the screw driver did not disturb them in the least. Ergo, not magnetic

g3xpert · #8 01-11-2021, 02:51 PM

Quote:

Originally Posted by snoop9erdog

Ok yes I should have stated no ferrous tools......but nobody has answered the question. What if i do use a normal ferrous tool? a big deal? Does it screw up the magnetometer innerds?

The installation kit comes with all non ferrous hardware already

This has caused problems in the past, it can introduce interference into the immediate vicinity of the very sensitive GMU 11 magnetometer. Your system would likely throw a Mag Anomaly flag some or all of the time, and because the GMU 11 feeds information to the GSU 25 ADAHRS, its resulting output can be degraded.

Thanks,

Justin

Av8torTom · #9 01-11-2021, 07:23 PM

I'm mounting my GMU 11 in the wingtip, and I'll be using nutplates to attach the wing tip to the wing. Will there cause interference?

Thanks

mfleming · #10 01-11-2021, 08:38 PM

Quote:

Originally Posted by Av8torTom

I'm mounting my GMU 11 in the wingtip, and I'll be using nutplates to attach the wing tip to the wing. Will there cause interference?

Thanks

According to Garmin, yes, but I'm not sure what you would do different.

This is right out of the G3X installation manual. Page 15-3

"Use nonmagnetic materials to mount the GMU 11, and replace any magnetic fasteners within 0.5 meter
with nonmagnetic equivalents (e.g. replace zinc-plated steel screws used to mount wing covers or wing tips
with nonmagnetic stainless steel screws)."