Southern Hemisphere Compasses

[LostOldTimer]

I understand a different compass is required for the Southern Hemisphere - such as Australia - Is this correct? and where is the best source for a Southern hemisphere compass?
What happens if you try to use a 'normal' Northern compass?

[Gross]

Yes you are best to use a compass balanced for the south. Rick at Compass Point maybe able to get a few from Silva (I guess it's for WMOC). You should be able to sell it on in Oz and get some cash back... otherwise email Oz and get the shop contact down there and order one in advance.

[MIE]

A northern hemisphere compass will still point to the north in Australia but
due the the Magnetic Field (of the Earth) you will need to hold it at an
odd angle to ensure the needle rotates properly. WMOC is not the best event
to try and work out the optimum angle to ensure that the needle will
swing freely. As Gross says -- best to buy one balanced for Oz

MIE

[DavidJ]

At BOC this year I was surprised to see a talented rival of mine had taken 12 minutes to find the first control compared to my less than 5. His excuse afterwards was that he had been late arriving at the event and, on finding a problem with his usual compass, had grabbed a spare from his (or the club’s) kit box. Heading to control 1 on a bearing took him away from the correct route. He gradually realised that the compass needle was sticking due to it being a Southern Hemisphere version.

[Gross]

Interestingly, for WOC 99 in Inverness the Swedish Team was using compasses specially balanced for Inverness [didn't help them much though!]

[AndyC]

Could this be why my compass keeps sending me the wrong way?
I've a compass for the NE and I'm using it in the Midlands?

On second thoughts it's more likely to be "operator error"

[madmike]

What happens if you try to use a 'normal' Northern compass?

LOT: because the needle is weighted differently, your northern compass can sometimes jam against the housing (I think declinination is the techy term) and you are therefore not always going in exactly the direction you think you are. If you are careful and make sure the needle is swinging freely you can use NH compass in SH; however, ......

On last years club tour to NZ I expounded the vitrtues of SH compass at great length on the flt over (I may even have bored a few people to sleep) and half the team thought I was making up SH compasses; until they went out into the sand dunes on day 1 and made all sorts of rough compassing errors 10 SH compasses purchased before day 2!

My advice is if you are spending 2 or 3 grand to orienteer down under, then 20-30 quid for a SH compass is lost in the noise and well worth it and that's the voice of experience talking.

[Big Jon]

LostoldTimer - send me an e-mail and we can discuss lending/borrowing a couple of southern hemisphere thumb compasses..... if you use a thumb compass! jon@big-jon.demon.co.uk