Compass Repair Kits

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Dave Reid
Posts: 49
Joined: Sat Sep 12, 2009 2:25 am

Compass Repair Kits

Post by Dave Reid » Sun Oct 14, 2018 11:15 am

LAS sell an Airpath compass repair kit, comprising some fluid and gaskets, for the princely sum of £46, so with VAT and postage, I'm looking at nearly £60. The self same kit bought in the US, retails for less than $12.
How annoying. I can make gaskets, but can anyone suggest where to get the correct fluid without selling the aircraft to pay for it?

Posts: 32
Joined: Thu Sep 25, 2008 12:04 pm

Re: Compass Repair Kits

Post by Leesr » Sun Oct 14, 2018 6:25 pm

If it's for a permit aircraft, use Johnson's baby oil.

Rob Lees

Harry Hopkins
Posts: 124
Joined: Fri Mar 13, 2009 10:58 am

Re: Compass Repair Kits

Post by Harry Hopkins » Mon Oct 15, 2018 10:08 am

In USA they are referred to as Whiskey compasses because they were filled with alcohol.

Gin might do the trick and is possibly less viscous than baby oil.

Nick Allen
Posts: 429
Joined: Wed Jan 02, 2008 12:00 pm
Location: Oxford

Re: Compass Repair Kits

Post by Nick Allen » Mon Oct 15, 2018 1:55 pm

I went to blag some fluid from the maintenance place on our airfield. The ever-helpful mechanic gave me a bottle labelled "Compass Fluid", gave me a look, and said "It's Jet A1".

Mark A
Posts: 125
Joined: Thu Jan 03, 2008 11:48 am
Location: South Warwickshire

Re: Compass Repair Kits

Post by Mark A » Mon Oct 15, 2018 11:21 pm

The compass fluid is treated as dangerous goods which probably accounts for the high import cost (oddly a compass containing the fluid is OK). The fluid is quite similar to white spirit, which should work OK, but is a bit less viscous.

It's a good idea to replace the diaphragm when servicing the compass as they are prone to swell and contact the compass wheel.

You should be able to buy the kit without fluid and use white spirit instead.
Mark Albery

Robin Birch
Posts: 3
Joined: Thu Sep 06, 2018 11:45 am

Re: Compass Repair Kits

Post by Robin Birch » Tue Oct 16, 2018 6:24 pm

Take care when using the kits as the rubber diaphragm only just seals the rear of the compass and the cover needs to be tightened very carefully. Also I've found that you can get two or three compasses out of one bottle of fluid.



Dave Reid
Posts: 49
Joined: Sat Sep 12, 2009 2:25 am

Re: Compass Repair Kits

Post by Dave Reid » Wed Oct 17, 2018 1:51 am

Thanks for the helpful replies. I'll crack on with the job... when using whiskey or gin, at least there's a source of enjoyment available in the cockpit!

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