Compass oil

mldpt

mldpt

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Hi Anybody out there able to tell me what oil do I need for my Sterring compass I now have a large bubble in mine and today I have worked out how to re fill it but what do I fill it with and where do I get it from.
Regards Mike
 
The only thing I can say is that there are different oils for different makes, its worth checking with a compass fixer (I found one in Yellow pages) I was told that th ewrong type of fluid could damage the diaphrams or seals? not sure how true this is though.

If it's lost fluid it could be that the diaphrams leaking (mine was) it seemed ok with bubble getting bigger and smaller as pressure and humidity changed and then it just dumped a load of oil one day and emptied on the cockpit floor.
 
This is a much more complex and controversial issue than you realise! The last time it came up there were daggers drawn on both sides of the issue, which is basically: oil or alcohol? Early compasses were filled with a mixture of alcohol and water. More recent ones, since about the 50's, are oil filled. I have filled two compasses (compii?) in my life, both with simple mineral oil. The results were entirely satisfactory. Others may tell you to buy special compass fluid (which I suspect is mineral oil), some from the alcohol persuasion will tell you to use vodka. Waste of vodka in my opinion!
 
Drain it and fill with baby oil - less than £1 a litre compared to £20 for 50 ml of oil...

That advise came from a reputable compass manufacture's agent...

PW
 
After many years of trying, on many different compasses, I now either throw the compass in the bin ,or if its expensve get it fixed properly.
The problem seems to be that if air has got in .then unless you can find the leak the bubble will just keep reapearing.
 
Baby oil will be too viscous if the compass was originally filled with something much lighter

Some use white spirit , some used an Esso product called Bayol which is no longer available, some used alcohol, etc etc.

Some folk have succesfully used ordinary paraffin (barbeque lighting fluid is a more highly refined version and is colourless)

It is important to get the correct fluid or at least an acceptable substitute not only from the viscosity point of view but to avoid wrecking the compass. The wrong thing can strip off all the markings!

Try Sirs Navigation (Google for it) or bpsc-marine who is a regular user of these forums
 
Yes, baby oil is mineral oil, mineral oil is liquid paraffin, liquid paraffin is lamp oil. They are all much the same with slight variations in viscosity which I'm quite sure the compass doesn't notice. But some compasses do want alcohol, although I haven't seen one myself.
 
I used white spirit to top up a plastimo contest compass and it mixed perfectly with the original fluid, I thought that if it was incompatible, the two fluids would separate out. The compass worked fine, but the fluid started to leak out again, but only when the very cold weather started, so I guess a new compass will be added to the (growing) list of things to get for this season.

Peter
 
Hi Thanks for your quick responce. I have bought a new compass on E-Bay so am now prepared to have a go I noticed the belows in the bottom and recon that once the filling plug is removed if I apply a vacum cleaner over the base this should draw the belows out and then I should be able to refill the compas till the oil is level with the filling hole replace the screw to plug the filling hole release the vacume and bob's your aunt. polish up the glass and should be as good as new, if not into the skip with it, it's given me good service for 15 years and not been looked after so it owes me nowt. sounds like a pint of baby oil from the chemist tomorrow, that could rais a few eyebrows, in the village.
Regards Mike.
 
[ QUOTE ]
... sounds like a pint of baby oil from the chemist tomorrow, that could rais a few eyebrows, in the village.
Regards Mike.

[/ QUOTE ]

Yeah I got a similar smile from the young (good looking) lady at the Tesco checkout too! /forums/images/graemlins/smile.gif

As said was advised of that course of action by major manufacture's agent.

PW
 
just a couple of further points
1.if you gently pull on the rubber bellows (you can usuially catch hold with your fingers) you may find a stream of bubbles coming from the leak - fix this or the bubble will come back
2.refilling is quite tricky - you fill- up screw in the plug -turn it over and find you still have a bubble; be patient tipping it back and forth and it can be done
3,you will need only a small amount of fluid so make sure whatever u use is compatible with the present fluid. i used baby oil and it was fine
 
As posted above Esso Bayol 35 was common in oil filled compasses until it was discontinued. I don't know what the official substitute for that is, but I did a fair bit of research when I needed 1.5l to refill my Whitlock pedestal steering compass and a good substitute in terms of viscosity over the expected temperature range, cloudiness (whatever the technical term is) etc. was clear Bartolene lamp oil from your local hardware store. The only major difference was that Bayol was odour free while lamp oil smells.

The Bartolene seems to work fine anyway - it's been in there for 18 months and the compass reacts as it should.
 
[ QUOTE ]
sounds like a pint of baby oil

[/ QUOTE ] It could make the compass so sluggish that it will be useless if it is intended to have something less viscous in it.

There is a way of checking candidate fluids against a few drops of the original.

Put a little of a possible liquid in a small glass vessel (a laboratory test tube would be ideal but I guess I am unusual in having a rack of them at home) Then add a few drops of the original and watch carefully as you mix them slowly together. If the two are the same then they will mix invisibly. If they are diffrerent they will almost certainly have different refractive indexes (indicies?) and you will be able to see the two liquids as they mix. That is assuming they do mix!
 
A smart way to do it, is to first put the compass in the freezer, together with the lamp oil. Fill it up, knocking the beast so bubbles will float to the opening and disappear. Usually a small one remains. After it warms up there will be no bubble left
 
Ours (made by Riviera) had something in it which smelled like turpentine, so I topped it up with turps from the decorators' shop (the real thing, not substitute) and it seems fine (one season so far). I also poured the old fluid out and flitered it - it was quite dirty.

But, as others warn, beware of using alcohol - I tried cleaning the card with meths and removed several characters before I realised the mistake.
 
[ QUOTE ]
baby oil is mineral oil, mineral oil is liquid paraffin, liquid paraffin is lamp oil

[/ QUOTE ] I think that statement is probably total rubbish.

Mineral oils are things like engine oils and other lubricants. I hope you won't be putting GTX on your baby's bottom. Mineral oils are carcinogenic for starters.

Lamp oil is similar to domestic paraffin or kerosene which will work quite well in your lamps but SWMBO points out that they won't work very well on liquid paraffin or probably baby oil. They will certainly smoke a bit.

Medicinal liquid paraffin may be similar to baby oil although it is even more viscous and again I would not recommend a mineral oil like engine oil as a laxative in place of it.

[ QUOTE ]
slight variations in viscosity which I'm quite sure the compass doesn't notice

[/ QUOTE ]
I can promise you that frequently topping up a leaky compass in an old Seacourse with liquid paraffin made it so sluggish that it became useless. Fortunately I eventually discovered that the correct fluid was white spirit.
It said so in the instruction book but the owner was so good at reading instruction books that he renewed the brake pads in his car when the bulb failure light came on!
 
I was told to use parafin by an old compass mechanic. I refilled my Danforth constelation which is still bubble free today as well as a seastrel moore also still doing its job.

Just now ive replaced a broken diafram in my current german path compass useing innertube and refilling with clear parafin, so far it works perfectly.
 
[ QUOTE ]
Drain it and fill with baby oil

[/ QUOTE ]
This doesn't work for all compasses. I tried it with a plastimo and the baby oil was a different viscosity, so the card because of the adjustment for the northern hemisphere would not lie horizontal. It did work however and was a very easy solution. If it doesn't work there is unlikely to be any damage done and you can drain and try something else.
 
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