Vintage compass fluid?

[ltcom]

Bought a nice WII era handbearing Type 06A compass. Some fluid missing. Before I phone around tomorrow anyone know correct fluid? Tests so far show it does not mix with white spirit or baby oil. So not oil based. Does mix with meths and vodka. I cant get clear meths. Will try rubbing alcohol. But very worried numerals.may come off if I message up. TIA.

 

[neil_s]

Before getting into the more complicated fluids - it might be distilled water.

 

[Poignard]

If it was water it would be useless in freezing conditions. I should think alcohol is a likely bet but it shouldn't be too difficult to find the correct stuff. There's a firm of instrument makers in Hull who might sell you some.

https://m.youtube.com/watch?v=xbve08uj4uQ

 

[ltcom]

Nice video. Searching past threads suggests it could be a mix of alcohol and distilled water (So freezing won't happen). Time for another test. Beautiful instrument.

 

[anoccasionalyachtsman]

I've refurbed a few different compasses now, and if it's not coconut oil then I use cheap Vodka. I did get given one where someone had used some sort of oil and the paint on the card had lifted, so I'd never use an oil if there was any doubt. Vodka seems to be completely harmless (to compasses, not Russians) so unless the low viscosity is a problem would always prefer that.

 

[VicS]

Nice video. Searching past threads suggests it could be a mix of alcohol and distilled water (So freezing won't happen). Time for another test. Beautiful instrument.

Dont f.... it by using the incorrect fluid.

If you want to experiment add a drop or two of the original to any candidate fluid mixtures in a clear glass vessel ( a laboratory test tube is ideal). If they are different they will almost certainly have different refractive indices and you will see the two liquids as they mix. When / if you find the right one you will not see the two fluids .

Better idea contact forumite Barry Philips of BPSC Marine https://www.bpsc-marine.co.uk/

Or Sirs Navigation https://www.sirs.co.uk/marine/repairs_and_spares

 

[ltcom]

Job done and hopefully finished. Distilled water mixed with my 3 test tubes of original fluid (either pure alcohol or water mix). So I added distilled water. Bubble gone. Won't be using it anywhere cold. Water seemed safer than adding alcohol. Looks lovely now.

 

[johnmcc]

I had a WW2 grid bomber compass on a previous boat, hung in - I think - the original gimbal rings. I topped that up a few times with surgical spirit. Still seemed fine when I sold it in 2013 after 34 years!

 

[DownWest]

I sailed across a bit of the med a long time ago in a a Fairey Atalanta. Only nav bits were an ex RAF compass and a Walker log. If we left the compass in the sun, the bubble got bigger with a hefty honk of alcohol..
Later on, the CAA surveyer told me to use gin in an aircraft compass. Didn't help in a French compass, when it stripped the numbers off.

 

[Spirit (of Glenans)]

Bought a nice WII era handbearing Type 06A compass. Some fluid missing. Before I phone around tomorrow anyone know correct fluid? Tests so far show it does not mix with white spirit or baby oil. So not oil based. Does mix with meths and vodka. I cant get clear meths. Will try rubbing alcohol. But very worried numerals.may come off if I message up. TIA.

Isopropyl alcohol.