Compass Fluid ?

graham

graham

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I have repaired (I hope ) a leak in a compass .

I kept the old fluid but it had a substantial bubble so need a bit more.

Its a plastic body and dome.In the past I have used surgical alcohol from the chemist and Vodka but that was a bron ze compass with glass dome.

Fluid that came out doesnt smell or feel like alcohol.

Any ideas?
 
There are a couple of different types of liquid used for compass damping. One as you say is alcohol based, others use a very light mineral oil. I had a bubble in the oil filled binnacle compass on our last boat and filled it with Lamp Oil which is paraffin with pretensions, completely satisfactory.
 
I refilled my Plastimo compasses with Johnsons Baby Oil, and wrote up how to do it in PBO Number 569 January 2014. Baby oil is a mixture of liquid paraffin and isopropyl palmitate, the latter made from isopropyl alcohol and palm oil. After four years the choice of Johnsons Baby oil (the unscented type) has proved to be a good one as the compasses have not suffered any damage and the oil seems to be the right consistency. One did leak a little, but that was due to the fact that the O ring under the filler screw was damaged, and a new O ring has solved the problem.
 
I've restored quite a few old compasses and have always tried to replace like for like. Snag is that people make their money by never admitting what the original really is. Until a few years ago I'd always used vodka if there was any doubt, but that backfired and softened the paint inside the case (not the card, thankfully). I've got a Sestrel to do which has had its card destroyed by something that smells a bit parafinnish, so don't try that! As above though, I've not had any trouble with baby oil, which I've used on everything since that mini disaster. I'm sure that it does damp a little more, but none that I've used it in have ever felt sluggish.
 
RichardS said:
Wouldn't something with a bit of viscosity like an oil of some kind (Lamp, Baby, Olive ;) etc) give a bit of useful damping?

Richard
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We had a leaky compass in an old Seacourse tiller pilot ( the big one with a remote compass unit not the Mini Seacourse that most people old enough to remember them at all will remember ) Somebody at some stage had said that the correct liquid for it was liquid paraffin so that is what we used, the medicinal stuff not kerosene. Eventually it became so sluggish that it became almost useless. Then one day I found the instruction manual ... and read that the correct fluid was in fact white spirit. Refilling with white gave the old beast a new lease of life, although it leaked out more quickly.

White spirit is not to be recommended for a compass with a graduated card however. Using it myself probably accounts for the reason all the lettering has fallen off the card of an old Seafix compass that I still have
 
When I had a large bubble I extracted some of the existing liquid to find out what was miscible - in my case it was very oily and white spirit did the trick.
 
agurney said:
When I had a large bubble I extracted some of the existing liquid to find out what was miscible - in my case it was very oily and white spirit did the trick.
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If you can extract some fluid add a drop or two to any candidate liquids and watch how they mix. If you do not see the drop of original as it mixes it means it has the same refractive index and the two are almost certainly the same. If you see it as it mixes it has a different RI and is therefore not the same.
A rack of laboratory test tubes comes in handy for this ........ but everyone has a rack of test tubes don't they? I'm not the only one surely?
 
Years ago this topic was a regular one. Consensus was to use white spirit. I settled on this and it worked fine for years. White spirit is cheap. Employees the old stuff out and refill.
 
Halo said:
Years ago this topic was a regular one. Consensus was to use white spirit. I settled on this and it worked fine for years. White spirit is cheap. Employees the old stuff out and refill.
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A compass repairer, eg forum member BPSC Marine ( http://www.bpsc-marine.co.uk/ ), aka Barry Philips, will be able to advise on the correct fluid or supply it if it is not something common.

A compass is far too expensive an item to risk being wrecked by the use of something unsuitable in order to save a few shillings

Barry has said in the past that they won't accept or attempt to repair a compass which has been filled with the wrong fluid .
 
VicS said:
A compass is far too expensive an item to risk being wrecked by the use of something unsuitable in order to save a few shillings
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When I acquired an old Sestrel Radiant with a bubble, I rang SIRS for advice. They asked me to sniff the fluid and when I said it smelled alcoholic, suggested that I use gin. Which has worked very well. Putting oil in would, as you suggest, have done all sorts of horrible things.
 
JumbleDuck said:
SIRS, who make Sestrel compasses, still list Bayol, which is the official non-alcohol fluid for them. They are very helpful on the phone.QUOTE]

But quite expensive - I think about 2 litres needed for a Sestrel Major. Perhaps Bayol is a contraction of Ba(b)yo(i)l? I refilled my Sestrel with Johnson's Baby Oil 10 years ago and it's fine still.
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JumbleDuck said:
When I acquired an old Sestrel Radiant with a bubble, I rang SIRS for advice. They asked me to sniff the fluid and when I said it smelled alcoholic, suggested that I use gin. Which has worked very well. Putting oil in would, as you suggest, have done all sorts of horrible things.
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Eeyore said:
JumbleDuck said:
SIRS, who make Sestrel compasses, still list Bayol, which is the official non-alcohol fluid for them. They are very helpful on the phone.QUOTE]

But quite expensive - I think about 2 litres needed for a Sestrel Major. Perhaps Bayol is a contraction of Ba(b)yo(i)l? I refilled my Sestrel with Johnson's Baby Oil 10 years ago and it's fine still.
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The Bayol use in some compasses is one of a range of Esso " Bayol" white oils

I believe the particular oil used in compasses is nla . If that is so then Sirs and others are using/ supplying a susbtitute
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