I have a Suunto A-10. A couple of months ago I went on a overnight snowshoe/backcountry snowboarding trip in the Adirondacks, the temp was about 5 - 20 Fahrenheit. When I got home I noticed my compass had an air bubble in the liquid. I really have no idea what exactly the liquid consists of, some sort of silicon/alcohol mixture maybe? I am sure someone here can answer that. Anyway the bubble has since gone. Should I be concerned about the integrity of my compass or should this be expected with the low temps due to the liquid possibly expanding/contracting?

As this is my only compass and they are pretty cheap I should probably have an additional one anyway, but am curious about the air bubble all the same.

Thanks,
Mike

Your Suunto is fine.This is a common mechanical reaction to extreme temperatures.

In general, the view of the compass makers is that a small bubble certainly doesn't harm the functionality of the compass and is fairly common in liquid-filled compasses, especially in very cold weather.

Still, at least with higher end compasses, if the bubble gets large enough to bother you, or interfere with the movement of the compass needle, most of the companies will repair the compass at little cost, or more likely no cost.

I've had to send a few compasses into Brunton for various repairs, and they've always been very good to me. I would assume Suunto would be similar, though I'm not sure where you'd need to send the compass (to Europe?).

BTW, from what I understand, the liquid is something similar to mineral oil - maybe with some anti-static agents added.

Ken

Right on, no reason to worry. It can happen to any liquid-filled compass in cold weather or during air travel (low pressure).

Wow. Great timing for the compass question. To answer your question before I possibly hijack this thread, a bubble will not harm the integrity of your compass. Bruntons are notorious for bubbles and I researched it pretty hard online.

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Thinking of swapping out the Silva Ranger I EDC for something lighter and smaller, like my Brunton 8096 Adventure Racing compass or actually was thinking of buying the Suunto A-10. I'll continue to back up with a micro dry button.

The 8096 and A-10 are both lighter (25% & 50% respectively) but the Ranger has a mirror which is my back up to the 2oz signal mirror i carry.

Not stuck on any one make/model. This is not a choice of a primary for the back country, just an around town, city travel compass.

Suggestions or thoughts?

Plenty of options. Speaking of Suunto, which just happens to be my favorite brand and is easily available almost anywhere on the planet, I believe the A-10 would make a fine backup compass. Of course, there are the A-20, 30 and 40, each a step up as far as the bells and whistles go. It all depends on what features you're looking for.

Another excellent choice would be the Arrow 20 (or 30). Very similar but somewhat more of a competition compass.
Arrow 20

Or even the M-9 if you like the idea of wearing a compass on your wrist. Easily the best wrist compass I've ever seen:
M-9

Though as you're probably well aware yourself, in the field where accuracy and reliability really matter nothing beats a mirror compass. Preferably one with a fairly large bezel (conducive to precision). My primary compass these days is the Suunto MC-2 with global needle. Not only does it work anywhere on the planet, the needle sets super fast and accuracy is superb. It's the kind of compass I wouldn't mind betting my life on in a serious situation.
MC-2

The Suunto 'A' models have fixed declination scales.

I MUCH prefer compasses with adjustable declination scales, such as the Suunto 'M' models - my own favorite being the M-3.

I also like the Brunton 8010G and 9020G, but the dials look a bit, well, cheap. The Brunton Eclipse models (8097, 8096, and 8099) are VERY high quality, but kind of expensive compared to the Suuntos.

I just looked up the price of the Brunton 8097 - about $26-$30. Not bad for such a nice compass.

I'd recommend one.

A litte-recognized feature of the 'Eclipse' compasses is the magnified bearing reading area - makes it MUCH easier to read for those of us with older eyes.

I have the Brunton 8096. Its a great compass.

I suppose this goes to the crux, does an EDC item need to be the best you own, life depends on it every time you use it, or something that is sturdy, dependable, lightweight and does what you need when you need it.

I guess in my mind, my most hardcore gear goes into my BOB or with me depending on the 'mission'.

(i.e. a cell phone will be in my EDC. A PLB in my BOB or on me if I go into the back country)

The A-20 would probably be just right for shooting an azimuth in town or in a open park. Its a 1/2 ounce lighter than the Brunton 8096. And the 8096 could stay in my BOB.

Be carefull not to fall into the 'cheap' trap.
The phenomenon of lost hikers deciding their compass was somehow faulty and relying on some 'mental template' of the terrain is not uncommon.

That 'cheap' Suunto would make the units used to discover this whole continent look pretty crude.

I mapped a archaeologic site previous to excavation using my Silva( present Suunto in the USA) Ranger. A visitng archaeologist decided I was seriously in error and proceeded to remap everything with his tripod mounted, solid brass surveyor's BRUNTON compass with assistance from a comely coed. In triumph, he announced my map was off 20 feet from the development company's survey marker.

It was rather unpleasant, pointing out the old AERO windmill that had been a local landmark for 60+ years was MY official surveying benchmark, and had been used a full 6 months before the county marker was placed there for future road improvements AND that my map was done in meters.

If you visit the Reagan Presidential Library, that Aero windmill is STILL there, while the survey marker is not.

Trust your gear.