Originally Posted by christep
This is just wrong - as a OneWorld Emerald you have access to any OneWorld airline lounge (F or J) when flying on a OneWorld airline from that airport that day. I have never had any difficulty at all with this (except once with FinnAir in Helsinki, where they took some persuading). The only exception is for AA EXPs flying on "domestic" North American flights.
I notice though that your profile says AA Plat, which is OneWorld Sapphire, not Emerald. In this case you would be refused access to F lounges, but you would have access to J lounges (with the same exception for North American flights).
I am going to agree with
christep on this one. With status there is no problem at all with getting into any OW lounge when flying any OW member airline. Where things are a little grey is when one has no status.
The only exception to this is when there are capacity issues and this is even clearly stated on the oneworld website. There are permanent capacity issues at airports like CDG so if you flying BA into LHR, with anything except BA membership, you won't get into the lounge. Fortunately these exceptions are few and far between.
CX and QF are pretty open and as long as you wave a F or J International boarding pass even without having any status, they will let you in. Unfortunately there is nothing on the oneworld site stating the full lounge access policy.