Sestrel compass fluid

Seagreen

Seagreen

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I know this topic was aired slightly a week ago, but I've two old sestrel compasses which need topping up, so "fingers on the buzzers, your starter for ten"...

First, my handbearing compass tells me to top up witha water alcohol mix of specifis gravity... (worn away). What's the mix, please?

Second, I've just bought an old brass sestrel steering compass of ebay, whose filling has turned brown! (obviously a non-standard top up by a previous owner). Apologies if I outbid someone.

Would the liquid for this be different, and if so, how?

Cheers all!
Mac:)
 
Only the do er can know what was done!!

What you should ask is what should i refill with! And hope it dosent clash with whats been used!

Sounds to me as if someone was experimenting and it dident work out!!! That can make re filling a question!

Please let us know what happens!!And dont believ what you read on lables??!!Be sure!
 
After a mega thread on this forum some years ago I used white spirit in my sestrel compass. It has worked like a charm ever since. If I had your compasses I would not hesitate to use White Spirit

Martin
 
I agree white spirit is used in some compasses and so are many other products.

Parafffin (kerosene not the viscous medicinal liquid paraffin) does seem to be suitable for some as well but barbeque lighting fluid is more highly refined and colourless but otherwise more or less the same ( I got the analytical chemists to look at bbq lighting fluid some years ago)
However the ONLY sound advice that can be given is to correctly identify the fluid for a compass and get some from a compass repairer. Put the wrong stuff in an you could wreck the compass, by stripping off the markings on the card for example, or by destroying seals.

Sirs Navigation, Google for them, or BPSC Marine, who posts on here, will be able to help
 
I tried to top up with isopropyl - the mixture turned into nail varnish remover and started attacking the innards!- instant milk!. I drained and filled with baby oil ( boat was going to warm med) and it works beautifully, just the right amount of damping. It took several nights of topping and settling to get the last bubble out. This was B&G RDF compass.
 
Give SIRS Navigation a ring on 01474 816320 or email to sales@sirs.co.uk ,they make Sestrel compasses and will be able to supply you with the right stuff. They'll also probably be able to tell you how to clean it out before refilling.
 
I'm already in touch with them /forums/images/graemlins/smile.gif , but just in case the cost gets prohibitive, (after all, we are all on a budget) I'd like to have a go at it myself. I've got a lot more to do (and spend /forums/images/graemlins/frown.gif ) before april.
 
If you use the wrong liquid and it bu**ers it up a new compass will make an even bigger hole in your budget.

However there is a little trick you can use to confirm that a potential liquid is the same as that already in the compass.

Put a small quantity of the candidate liquid in a small clean dry clear glass vessel. A laboratory test tube is ideal (everbody should have a rack of test tubes!)

Extract a very small quantity of the original liquid from the compass, a few drops should be enough, add it to the liquid in the tt and observe carefully. If the liquids are the same they will mix quite invisibly but if they are different they will have different refractive indicies and you will be able to see the two as they mix. (If you have got it totally wrong then they might not mix at all.)

You will be able to experiment with alcohol water mixtures as well to get a mixture that is about right for the compass you know has that in it, but do you have a source of alcohol. Ethyl alcohol (ethanol) is available as Industrial methylated spirit (IMS) but I do not know if you will be able to get it without a C&E authorisation. You certainly won't get pure ethanol. I doubt if it will be methyl alcohol (methanol) but it could be isopropyl alcohol (isopropanol or propan-2-ol)

It is not absolutely foolproof I guess but it should eliminate many incorrect liquids.
 
Good advice. I actually suspect that a previous owner has tried to fill the compass with a water mix, as the fluid has turned rusty brown! (The horror! Filling a compass with water) and seems to have reacted with the card mounting screws. I think that this is no more than superficial and the card can be cleaned up lovely provided I use a non aqueous fluid. My only problem is that the ink on the card may be etched by using an alcohol or white spirit.
 
[ QUOTE ]
but what is 'C&E Authorisation'

[/ QUOTE ] Customs and Excise

At one time we had a book of permits to obtain IMS and one had to be sent with each order but later they did away with the permits and we just had a letter of authorisation to buy a certain quantity a year. I packed up working for a living six and a bit years ago so things could have changed again in that time. (when we had some pure alcohol the C&E Officer used to come about every six months and inspect our stock and the records of its useage until we decided to dispose of it, but that's another story. So is the time the C&E man turned up when I had been distilling some wine!)
 
Don,t know if the fluid in my Sestrel is original or not but I topped it up with Johnsons Baby Oil and that has worked out fine
 
My compass was filled with oil. Which turned out to be bayol, which is used in cosmetics. I read somewhere that this was chemically and physically the same as baby oil.

I filled mine this year with baby oil. Worked out fine until it leaked from a different spot but it looked perfect and the compass moved perfectly whilst the boat bounced about....
 
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