Refilling a compass

monkfish24

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What do I use to refill a compass?

Is it alcohol?

It is on my dinghy and is full of grit and very slow with very low oscillations which tells me its not full of whatever it should be full of.
 

VicS

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It could be any one of many fluids.

Get the wrong one and you could mess up the compass.

The only sound advice you can be given is to obtain the correct fluid from a compass repairer.

Alcohol would not be high on my list of probable fluids. White spirit would be higher, but it may have a more viscous fluid in it to provide more damping.

What make is it. Somone might know what fluid can be used
 

electrosys

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As Vic says - different compasses, different fluids. Use the wrong fluid and you can dissolve away the rose markings ...

You'll also need to find out why the fluid has leaked out - it might be just the filling screw seal, which can easily be replaced, but it could also be a sign that the case-to-glass seal has passed it's sell-by date.
 

chewi

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Johnsons Baby Oil

I did my plastimo with johnsons baby oil. The smell of the original was familiar , Mrs C said well its got to be an oil. bought a bottle and the smell was the same, mixed some and found no separation afterwards so in it went. cause of leak was a crack acrosss the filler, so by removing enough of the original I could araldite the crack, then refill.
 

VicS

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I once used the wrong fluid, and the plexi lens shattered.
Can't remember what I used.

I think ordinary alcohol , ethanol, is safe to use with acrylic. Propanol isn't.

But you underline my statement that the only sound advice is to obtain the correct fluid
 

Elessar

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It could be any one of many fluids.

Get the wrong one and you could mess up the compass.

The only sound advice you can be given is to obtain the correct fluid from a compass repairer.

Alcohol would not be high on my list of probable fluids. White spirit would be higher, but it may have a more viscous fluid in it to provide more damping.

What make is it. Somone might know what fluid can be used

Had a big bubble in the top of mine.
Used White spirit.
Perfect.

Struck lucky for once I guess........
 
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VicS

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Older Plastimo compasses used one of the Bayol oils. As Esso product that is no longer available.
A compass repairer should have a replacement.

Forumite Neil_S topped his up with ordinary domestic paraffin. AFAIK several years later it is still OK.

Personally I would have used barbecue lighting fluid. Our analytical chemists found that to be a more highly refined paraffin.
 

JayBee

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Have a look at this website:

http://www.trademarklondon.com/compass_fluid_32.html

Purified kerosene, AKA clear lamp oil or highly refined paraffin, works in many compasses. I have even used it successfully to replace xylene in a bubble sextant.

Many Sestrel compasses were filled with alcohol and the SG of the alcohol water mix was marked on the bowl.

Two things:

There's always a chance that a change of fluid might damage the compass.
Don't attempt a top-up if you don't know what's in the bowl already. Better to empty it completely and refill. But... some compass bowls must not be allowed to dry out as this will damage the internal paint.

Good luck!
 
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whipper_snapper

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I topped-up my Plastimo bulkhead compass with white spirit after receiving advice from a Plastimo compass dealer. They said:

There is not a proprietary compass fluid available, the main ingredient is white spirit or turpentine substitute usually with a small amount of gelatine to increase the damping effect of the fluid.

Worked for me.
 

nortada

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How do I replenish the oil in a Plastimo Olympic 135 steering compass? i.e. where is the replenishment screw and how much stripping down to I have to do.

White spirit appears to the preferred fluid?

Must already be a thread/post covering this so just please point me at it.

Ta
 

nemodreams

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I've done a couple of small ones - white spirit has seemed fine. However - be prepared to totally immerse the compass in the fluid if you don't want a real hassel with that last little bubble !
Also - although white spirit is pretty mild stuff, when you totally immerse both hands in it, it gets a bit twitchy. Wear some gloves :ambivalence:
 
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