Compass Question

[Virgil]

This is going to sound like a really dull question but it's beginning to really bug me so here goes.

Do the oil fills accross different types of compasses vary with manufacturer, type, style, age etc? The reason for the question is that the more navigation work I do, search and recovery etc, the more I am convinced that the compass in the Mares console that I've used for some time is very slow at turning and settling. Initially I thought it was maybe a problem with me not keeping the unit level at all times but now I don't think that's the problem.

Spoke to a fellow diver who said it seemed a little slow to him but I don't know if it's just something that I have to live with or if there's a better model to invest in.

Any ideas?

 

[The Kraken]

The fluid doesn't age, but there are various fluids used to fill compasses. Most use a glycerin compound and these can vary in viscosity. Viscosity, of course, can vary with temperature.

Are you starting to dive colder temperatures or diving in colder weather?

 

[Virgil]

Are you starting to dive colder temperatures or diving in colder weather?

That's a fair point and one I hadn't thought of. I do the majority of my diving in the UK and it rarely gets much higher than around 15 degrees celcius, (what's that, around 60 fahrenheit), and recently during the winter it's been less than 10 degrees celcius, (on Sunday we were doing search patterns looking for a small fishing boat wreck and it was down to 6 degrees celcius).

If it is the temperature are there other types of fluids or will I just need to learn to be a little more patient?

 

[The Kraken]

It's rather difficult to say from this viewpoint.

Perhaps you could check out some of the local dive shops that carry different brands of the same type product and make an in-store comparison.

Other than that, I guess you'll just have to learn patience.

 

[aquaticaggie]

Any Bubbles in the compass? Got some in an old compass of mine and it stuck sometimes or tracked really slow, just my .02

 

[teknitroxdiver]

Could be bubbles. In a wet compass, when the outside pressure becomes a large enough amount less than the internal pressure, some oil seeps out, and then when the pressure goes back down some air gets sucked in. Problem is, air never goes out, only oil, so over time you'll get bigger bubbles until they become big enough to make a problem.

Or, it could be that you're in colder water and the oil is a thicker viscocity.

 

[Virgil]

Training in the pool on Sunday which is going to be much warmer so I can see if the temperature makes any difference. Will check for bubbles which I haven't done. Otherwise a little more patience.