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View Full Version : I keep getting bubbles...compass issues



pakratt
04-20-2008, 22:21
I switched over from a military compass two years ago and have tried going to a lighter compass. Tried several brands and styles-- Silva, Brunton, etc-- all styles, brands, and price ranges...still every compass I have purchased gets bubbles in it. I take really good care of my equipment-- and I hike in the 3000 ft to 8000 ft range most of the year...



Any insight to this?

take-a-knee
04-20-2008, 22:23
I switched over from a military compass two years ago and have tried going to a lighter compass. Tried several brands and styles-- Silva, Brunton, etc-- all styles, brands, and price ranges...still every compass I have purchased gets bubbles in it. I take really good care of my equipment-- and I hike in the 3000 ft to 8000 ft range most of the year...



Any insight to this?

Take/mail it back, it is defective. It is probably still accurate enough for trail hiking but I wouldn't want it. I never got a bubble with a GI lensatic:). That is the only compass to use at night.

Appalachian Tater
04-20-2008, 22:25
Over time, the needle on any compass may begin to act sluggishly, even appear to stick to the bottom of the liquid-filled housing—as you have indicated yours is doing. Most often, this is due to a build up of static electricity within the housing and can be corrected by simply rubbing a small amount of water directly over the housing to disburse the static charge.

It is not uncommon for a small bubble to appear in the liquid-filled housing when you are using your compass in high elevations or in temperatures below freezing. The bubble forms because the fluid within the housing contracts or expands at a faster rate than the housing, resulting in a "vacuum" bubble. This bubble will not affect the performance of your compass as the liquid's sole purpose is to dampen or slow down the movement of the magnetic needle. Typically, any bubble will disappear when the compass is returned to room temperature and / or lower elevation. If the bubble remains, as appears to be the case with your compass, it is possible to correct the situation by placing the compass in a warm (not hot) spot, such as a sunny window sill. Do keep an eye on the bubble if it refuses to depart. Should the bubble grow in size, you might have a small, almost imperceptible leak in the liquid-filled compass housing and that means you will need a new compass.

http://www.adventuresportsonline.com/navigationcompass.htm

budforester
04-20-2008, 22:42
I've had this bubble problem in the high country, and fuel bottle becomes pressurized, packaged foods puff up. My bubbles always re- dissolved when returned to earth. My present compass is not liquid- filled... it saves a little weight, it's good enough to make tobacco sacrifices to the four directions, and I don't do much orienteering.

Rain Man
04-21-2008, 10:06
Any insight to this?

I have both Silva and Suunto compasses and if I'm not mistaken both of the owners manuals say this may happen at altitude and is not a concern.

See if yours doesn't say the same thing?

Rain:sunMan

.

BR360
04-21-2008, 10:45
Bubbles are a significant problem if they are large enough to push the compass needle from indicating magnetic North.

You might be able to continue to use them if you hold them with the bubble to East or West, but you need to take several readings to make sure the needle is not dragging on the housing, thus creating another type of error.

johnny quest
04-21-2008, 11:28
what above posts say about the bubble is corret.
it comes down to the accuracy needed from your compass weighed against compass weight. no, i wouldnt carry my tritium filled military issue lensatic on an a. t. thru hike, its overkill. BUT if i was bushwacking in alaska or canada that weight would be more than reasonable.

pakratt
04-23-2008, 00:43
Great feedback thanks--
I think for general directions I will continue to use-- for the bushwaking I will use the mil-spec one

Thanks again--

johnny quest
04-23-2008, 09:13
and just for conversations sake...the m2 artillery compass is the best ive ever seen. reads in mils or degrees. will attach to a tripod (or maybe hiking stick) but heavy as hell.