On Friday, August 14, 2015 at 5:52:17 PM UTC-7, MNLou wrote:
I am trying to install a Precision Vertical Card Compass in my LAK17at.

My first attempt was in the instrument panel. That didn't work due to too much magnetic interference from the various speakers "under the hood".

I then moved the installation to the top of the left side of the glare shield as far forward as possible. Again, there is too much interference - source unknown. Could be magnetic, could be metal.

My next attempt will be to move the compass again and add some shielding to try and mitigate the interference.

Any good ideas on how to achieve a successful installation?

Thanks in advance for your help!

Lou (I have also posted this to the LAK17 Yahoo Group.)

Lou,

You might try this, it has worked for me on an old Aeronca as well as on modern ships.

Center the compensating magnets that are built in to the compass. Temporarily install the compass in the most desired location using non-magnetic screws (hint, you can paint SS screws black etc. or use brass).

Turn glider to the heading that will maximize compass error. Using a suitable bar or rod magnet (not a horseshoe or circular type) orient and position the magnet (using double sided tape or other temporary means) to the side of the compass and far from the compass as possible while still having the magnet neutralize the compass error.

Check the other cardinal directions for error as well. If the error is great on any heading, compromise the original magnet position to minimize error in both headings if need be. Some error is okay, it's just preferable to even it out as the compass is swung.

Now proceed with the normal compass swinging procedure using the built in compensating screws.

Don't forget to more permanently mount that magnet with hot melt glue or epoxy putty etc. Not good to later find that magnet on the floorboard.

bumper